17 results about "Poynting vector" patented technology

To provide a measuring device capable of specifying a leakage direction of noise.SOLUTION: A measuring device includes a probe 2 having a loop-shaped electrode terminal which is electromagnetically coupled with an object to be measured and through which an electric signal corresponding to characteristics of an electromagnetic field flows, and two first and second output terminals connected to the electrode terminal. In addition, the measuring device includes an electric field measuring unit that executes a process of extracting an electric field signal based on a first output-signal I1 outputted from the first output-terminal and a second output-signal I2 outputted from the second output-terminal, and a magnetic field measuring unit that executes a process of extracting a magnetic field signal at the same timing as the electric field measuring unit based on the first output-signal and the second output-signal. The measurement device calculates a pointing vector by performing a cross-spectrum operation on the electric field signal and the magnetic field signal extracted at the same timing, and stores data indicating the calculated pointing vector.SELECTED DRAWING: Figure 1

This invention discloses a tunnel advance detection method based on point spread function correction, comprising: setting up receiver points and shot points, and acquiring observed seismic data; constructing a rectangular grid tunnel geological model; given a velocity model, performing forward modeling to obtain the forward propagation wavefield; using the seismic data to propagate backward in time to obtain the backward propagation wavefield from the receiver points, and obtaining the reverse time migration imaging result through cross-correlation imaging conditions; using the Poynting vector method to obtain the propagation angles of the forward propagation wavefield from the shot point and the backward propagation wavefield from the receiver point; decomposing the wavefield into beam superposition based on the propagation angles, and then obtaining the local illumination matrix; performing coordinate transformation on the local illumination matrix to obtain the angular domain point spread function; and using the point spread function to correct the reverse time migration imaging result to obtain the corrected imaging result m. psf This invention can obtain a more accurate angular domain point spread function and can be used to correct tunnel advance detection imaging.

The invention discloses an angle gather extraction method and device based on construction direction constraint, electronic equipment and a storage medium. The method comprises the following steps: extracting an underground structure angle based on an earlier-stage migration imaging result or a speed model; calculating a shot point end Poynting vector based on an underground structure angle and a wave equation forward propagation wave field; calculating a normal vector of an underground reflection interface based on the underground structure angle; calculating an underground local reflection angle and a local azimuth angle based on the shot point end Poynting vector and the normal vector; an angle domain imaging condition is applied, corresponding reverse time migration is stored based on an underground local reflection angle and a local azimuth angle to obtain an imaging value, and a high-precision omni-directional angle domain common imaging point gather is formed. According to the method, the angle gather precision loss caused by inaccurate detection point wave field Poynting vector direction is avoided, and the precision of the omnibearing angle domain common imaging point gather is improved, so that the seismic imaging quality is remarkably improved.

A laser apparatus with non-collinearly phase-matched frequency mixing includes a nonlinear crystal generating an output laser beam from non-collinearly phase-matched frequency mixing of first and second input laser beams. The output laser beam is subject to walk-off in a walk-off plane. The second input laser beam is less powerful than the first input laser beam. The first input laser beam is directed to more closely align its Poynting vector to the output beam Poynting vector than in collinear phase matching. To achieve good spatial overlap in this phase matching scheme, the second input laser beam is elongated in the walk-off plane, such that the second input laser beam has a greater transverse size than the first input laser beam in the walk-off plane. This non-collinear phase matching scheme is capable of achieving an improved beam quality of the output beam, as compared to collinear phase matching with circular input beams.

The invention belongs to the technical field of elastic wave reverse time migration, and particularly relates to a decoupling Poynting vector based on divergence and rotation operators and an application method of the decoupling Poynting vector in elastic wave reverse time migration, and the method comprises the following steps: P wave and S wave decoupling and Poynting vector calculation based on the divergence and rotation operators; the invention relates to an elastic wave RTM imaging condition based on decoupling Poynting vector constraint. According to the method, the Poynting vector calculation method compatible with divergence / rotation wave field decoupling is developed theoretically, the comprehensive advantages of the method in the aspects of improving the elastic wave RTM imaging quality (especially the reliability of PS wave imaging), effectively suppressing noise and improving the calculation efficiency are shown in the practical application level, and the method has important scientific value and wide application prospects and is worthy of popularization and application. And an effective new way is provided for further improving the practical level and the imaging precision of the elastic wave RTM under the existing computing resource condition.

The invention discloses a tunnel advanced detection method based on point spread function correction, and the method comprises the steps: setting a detection point and a shot point, and collecting observation seismic data; constructing a rectangular grid tunnel geologic model; giving a speed model, and performing forward modeling to obtain a forward transmission wave field; seismic data is used for back propagation in time, a back propagation wave field from a detection point is obtained, and a reverse time migration imaging result is solved through a cross-correlation imaging condition; obtaining a forward propagation wave field propagation angle from a shot point and a backward propagation wave field propagation angle from a detection point by using a Poynting vector method; decomposing the wave field into superposition of wave beams according to the sum of the propagation angles of the wave field, and further solving a local illumination matrix; performing coordinate transformation on the local illumination matrix, and solving an angle domain point spread function; and correcting the reverse time migration imaging result by using a point spread function to obtain a corrected imaging result mpsf. According to the invention, a more accurate angle domain point spread function can be obtained and is used for correcting tunnel advanced detection imaging.

The invention discloses a system and a method for generating Poynting vector optical skyrmion based on tightly focused second-order circularly polarized vortex light, and belongs to the technical field of light field regulation and control. The method comprises the following steps: firstly, converting incident light into left-handed or right-handed circularly polarized light through a polaroid and a 1 / 4 wave plate, and then loading a specific topological charge value for the left-handed or right-handed circularly polarized light by using a spiral phase modulator; the tight focusing optical unit is continuously used for tight focusing, and the Poynting vector optical Skyrmion is preliminarily generated; then annular amplitude shaping is carried out on the light field through an annular amplitude modulator, and according to the Richards-Wolf vector diffraction theory, it is calculated that the stable and efficient Poynting vector optical Skyrmion tubular structure can be generated in a three-dimensional free space in a focusing field after second-order circular polarization vortex light passes through a tight focusing optical unit. The optical skyrmion topological characteristics and spatial form are controlled by regulating and controlling polarization, phase, amplitude and focusing conditions of the light field.

The present disclosure provides a method and system for stabilizing a Poynting vector of a seismic wavefield. The method includes: adjusting an amplitude of a time derivative of the seismic wavefield, and computing a Poynting vector of the adjusted time derivative of the seismic wavefield to obtain a first Poynting vector, where a difference between the amplitude of the first Poynting vector and the amplitude of a second Poynting vector is within a set range, and the second Poynting vector belongs to the seismic wavefield; and conducting operation on the second Poynting vector and the first Poynting vector to obtain a final Poynting vector of the seismic wavefield. The present disclosure addresses instability of Poynting vectors computation.

Systems, methods and apparatus are provided through which in some implementations an experimental apparatus to modify gravity includes an electrically conducting dome, three or more electrically conducting coils attached to the interior of the electrically conducting dome, and a power source electrically coupled to the electrically conducting coils, the electrically conducting coils configured to generate rotating electromagnetic fields that form a Poynting vector vortex, that produces a gravity force that is perpendicular to the Poynting vector vortex.

The application provides a background velocity field reconstruction method and device based on reflected wave waveform inversion gradient preprocessing, a computer readable storage medium and an electronic device. The method comprises the following steps: based on near-offset information, inverse time migration is performed by calculating a Poynting vector, and a reflected wave field is obtained by reverse migration; the gradient of the velocity is calculated by using a reflected wave full waveform inversion technology based on an adaptive error function, the gradient of the velocity is preprocessed by using illumination energy compensation, the gradient of the preprocessed velocity is used to update the background velocity field, and a more accurate background velocity model is obtained. When the method is applied to model inversion, a more accurate background velocity model can be obtained, and the quality of a migration profile is significantly improved.

A laser apparatus with non-colinear phase-matched frequency mixing includes a nonlinear crystal from which the output laser beam is generated from a non-colinear phase-matched frequency mixing of a first input laser beam and a second input laser beam. The output laser beam undergoes a walk-off in the walk-off plane. The second input laser beam is lower power than the first input laser beam. The first input laser beam is directed to align its Poynting vector more closely with the output beam Poynting vector than colinear phase matching would. To achieve good spatial overlap in this phase matching scheme, the second input laser beam is stretched in the walk-off plane so that it has a larger lateral size in the walk-off plane than the first input laser beam. This non-colinear phase matching scheme makes it possible to achieve improved beam quality of the output beam.

The invention discloses a wave field direction calculation method and device based on a stabilized Poynting vector, electronic equipment and a storage medium. The method comprises the following steps: calculating a wave equation forward propagation wave field through a finite difference algorithm based on a migration velocity field and seismic wavelets; calculating a first gradient operator and a first time derivative of a forward propagation wave field of the wave equation; calculating a first Poynting vector of the forward propagation wave field based on the first gradient operator and the first time derivative; calculating a second gradient operator corresponding to the first time derivative and a second time derivative; calculating a second Poynting vector of the time derivative wave field based on the second gradient operator and the second time derivative; and constructing a stabilized Poynting vector of the forward propagation wave field based on the first Poynting vector and the second Poynting vector. According to the method, the calculation instability of the Poynting vector at the local extreme value is effectively eliminated, the efficient calculation of the real propagation direction of the seismic wave field is realized, and the extraction precision of the angle gather is improved.

The invention discloses a multi-node parallel output angle gather extraction method and device based on adaptive decomposition, electronic equipment and a storage medium. The method comprises the following steps: calculating the number of nodes for angle gather output; decomposing along the Y direction based on the node number, and calculating the output range of each node; calculating a shot point end Poynting vector and a detection point end Poynting vector in the forward transmission process and the backward transmission process of the wave equation by adopting a finite difference algorithm, and further calculating an underground local reflection angle and a local azimuth angle; and respectively applying an angle domain imaging condition based on the output range of each node, storing corresponding reverse time migration according to the local reflection angle and the local azimuth angle to obtain an imaging value, obtaining a local angle domain common imaging point gather of each node, and reducing the local angle domain common imaging point gather as an overall angle domain common imaging point gather. According to the method, the computer memory requirement required by the angle gather can be effectively reduced, the calculation efficiency is improved, and the calculation cost is reduced.

The application discloses a kind of wind turbine blade clearance monitoring method and system based on magnetic ranging, electromagnetic transmitter is installed on blade tip, electromagnetic signal is emitted by electromagnetic transmitter;Magnetic ranging sensor is installed on tower drum, and the electromagnetic phase of blade tip is obtained by magnetic ranging sensor;Electromagnetic transmitter selects electromagnet to form electromagnetic field in blade tip range, electromagnetic signal is emitted by electromagnetic transmitter to magnetic ranging sensor, the electromagnetic phase of blade tip is obtained, based on the electromagnetic phase of blade tip obtained, data is comprehensively processed according to Poynting vector, after processing, it is transmitted to the main control of wind turbine, and the main control is optimized according to actual situation Paddle blade clearance.The application can effectively improve the data accuracy of blade clearance monitoring, reduce the difficulty and cost of blade clearance monitoring installation, and can effectively monitor the blade motion curve during the operation of wind turbine, ensure the accuracy and real-time of monitoring.

The invention discloses an earthquake attenuation compensation method based on an angle domain common imaging point gather, and relates to the technical field of exploration geophysics, the method comprises the following steps: firstly, carrying out Dix inversion on a migration velocity model, solving an imaging ray domain wave equation by using a space eight-order time second-order staggered grid, and carrying out time migration by using a time consistency principle cross-correlation imaging condition; and an uplink wave field and a downlink wave field are separated in an imaging ray domain, and Hilbert transform is fused to construct an auxiliary vector, so that the oscillation defect of a traditional Poynting vector is thoroughly eliminated, and the high-fidelity ADCIGs is generated. The method has the beneficial effects that a brand new way is created for realizing stable Q field inversion and directional compensation in an angle domain, an angle-related absorption attenuation model can be constructed by utilizing high-precision incident angle information in ADCIGs, and the global averaging processing limitation of traditional inverse Q filtering is broken through.