459 results about "Surface wave" patented technology

The invention provides an airfield pavement detection method based on an earthquake background noise imaging technology, and relates to the technical field of airfield pavement detection. Comprising the following steps: acquiring seismic background noise data of an airport pavement to be measured; preprocessing the seismic background noise data to obtain preprocessed noise data; carrying out cross-correlation calculation on the preprocessed noise data and carrying out empirical Green function extraction; according to the empirical Green function, a surface wave group velocity frequency dispersion curve is extracted by adopting spatial autocorrelation and multiple filtering methods; inverting shear wave velocity distribution of each layer of the pavement based on the surface wave group velocity dispersion curve, and constructing a three-dimensional velocity model; determining a shear wave velocity distribution diagram according to the three-dimensional velocity model; and determining a detection result of the airfield pavement to be detected according to the transverse wave velocity distribution diagram. According to the invention, the problems of low detection precision and poor real-time performance of a common detection technology in the prior art are solved.

The invention discloses a seismic surface wave suppression method based on EWT-Curvelet, and belongs to the technical field of seismic exploration data processing. The method comprises the following steps: firstly, performing empirical wavelet transform (EWT) on post-stack seismic data channel by channel, extracting a frequency localized modal component through adaptive spectrum segmentation, and constructing a surface wave noise model; then converting the model to a curvelet domain, performing physical constraint filtering at a specific scale and in a nearly horizontal direction, and combining pixel connectivity analysis to suppress a continuous noise region; and finally, reconstructing and optimizing noise through inverse transformation and removing the noise from the original data. The method has the advantages that the modal aliasing problem is solved through channel-by-channel adaptive spectrum segmentation, a surface wave energy dense region is accurately locked by curvelet domain scale-direction combined filtering, isolated effective signals are protected in combination with connectivity analysis, high-precision suppression of surface waves is efficiently achieved in a non-iterative mode, meanwhile, the structural integrity of reflected waves is kept, and high-precision suppression of the surface waves is achieved. The seismic section signal-to-noise ratio and the geological interpretation precision are remarkably improved, and the method is suitable for land seismic exploration data processing.

The invention provides a method for detecting a welding seam by adopting an ultrasonic flaw detector, and belongs to the technical field of welding seam detection. The welding seam is divided into small welding sections, and each small welding section is subjected to multi-direction ultrasonic scanning; a scattering attenuation coefficient and a signal-to-noise ratio parameter are calculated to determine an optimal detection position direction vector group and an optimal time frequency group, and then a high-frequency narrow pulse probe is matched with a phased array focusing technology to carry out second detection according to the optimized parameter; and the identified defects are classified and evaluated according to the near surface blind area characteristic parameters, secondary verification is performed by adopting a surface wave supplementary detection algorithm, and finally a weld defect position distribution diagram is generated, so that the technical problem of low defect detection accuracy caused by serious ultrasonic scattering attenuation of a coarse grain structure weld material is solved.

The invention discloses a mountainous area wind field downscaling optimization method based on high-precision simulation, and relates to the technical field of meteorological numerical simulation, and the method comprises the steps: obtaining the terrain elevation data and meteorological monitoring data of a target mountainous area, recognizing slope abrupt change points, constructing a spiral sampling path, calculating a slope change value, determining the distance between sampling points, and generating target sampling data; performing orthogonal decomposition on the sampled data to obtain a frequency component, calculating a surface fluctuation coefficient, and constructing a boundary disturbance equation to obtain surface stress distribution; calculating an airflow motion state based on surface stress distribution, solving a vorticity equation to obtain vorticity characteristics of a leeward area, and calculating airflow motion correction parameters; and carrying out downscaling iterative operation on the corrected parameters and the meteorological monitoring data to generate target area wind field data with hectometer-magnitude spatial resolution. The simulation precision of the local wind field under the complex terrain condition is improved.

The invention discloses a multi-wave chromatography and reflection combined detection method and device for a thin-covering-layer urban active fault and a medium. The method comprises the steps that longitudinal wave seismic data and transverse wave seismic data are collected; recording vertical component data based on the longitudinal wave seismic data for first arrival travel time pickup and tomography inversion to obtain a longitudinal wave velocity structure model Vp; extracting Rayleigh surface wave frequency dispersion through the vertical component data and carrying out multichannel surface wave analysis inversion to obtain a transverse wave velocity structure model Vs; calculating a longitudinal and transverse wave velocity ratio parameter structure model Vp / Vs, and calculating to obtain a Poisson's ratio parameter structure model v; obtaining a longitudinal wave (P wave) reflection profile and a transverse wave (S wave) reflection profile; identifying and summarizing into an interpretation fracture set Fc, and recording key elements; and by taking the interpretation fracture set Fc as a structural skeleton, completing unified registration and superposition display on Vp, Vs, Vp / Vs and v, a longitudinal wave reflection profile and a transverse wave reflection profile, and outputting a shallow underground structure comprehensive interpretation map of the thin covering layer region.

The invention relates to the technical field of ocean new energy technology utilization, and discloses an oscillating water column type wave energy power generation system with an energy gathering structure at the bottom, which comprises a jacket, an air chamber, a turbine power generation system, a radar altimeter, an infrared camera, an airflow velocity sensor, a control host and a bottom energy gathering assembly, the bottom energy-gathering assembly is installed at the lower end of the air chamber and provided with a transmission mechanism, reflection and diversion of seawater at the bottom of the air chamber are achieved through the arranged horizontal bottom plate and the two symmetrically-arranged energy-gathering plates, energy gathering beyond the width of the air chamber is completed, and opening and closing of the energy-gathering plates are synchronously controlled through the transmission mechanism. And the amount of seawater flowing into the air chamber from the water inlet is changed. According to the wave energy power generation system, the oscillation intensity of the water column in the air chamber can be adjusted according to changes of sea surface waves, the speed of the generated air flow can be matched with the optimal working frequency of the turbine power generation system, the power generation efficiency of the device is guaranteed, and the oscillation water column type wave energy power generation device can be protected and prevented from being impacted by sea waves.

The invention relates to the technical field of helicopter aerodynamic force simulation, and discloses a sea rescue helicopter rotor aerodynamic force simulation method and system. The method comprises the following steps: acquiring a rotor wing downwash airflow historical speed data set, a historical sea surface wave data set and a historical aerodynamic pressure data set monitored within a preset historical time range; executing a dynamic volatility analysis process on the three types of historical data sets to generate a speed volatility index, a sea surface wave volatility index and an aerodynamic pressure volatility index; taking the three types of volatility indexes as guide parameters, performing adaptive search operation in a rotor aerodynamic force simulation parameter database, and determining an optimal simulation time interval; and performing numerical calculation simulation on pneumatic coupling between the rotor wing and the sea surface according to the optimal simulation time interval to generate a simulation data sequence, performing feature extraction and classification on the simulation data sequence by using an aerodynamic force recognition model, and outputting a rotor wing aerodynamic force simulation result.

The invention relates to the technical field of sensors, and provides a metamaterial biosensor and a using method, the metamaterial biosensor comprises a surface wave sensing structure used for constraining conventional electromagnetic waves into surface electromagnetic waves and guiding the surface electromagnetic waves with compressed wavelengths to be transmitted along a preset path so as to generate inter-field interaction with human tissues, and the surface wave sensing structure is used for transmitting the surface electromagnetic waves; and sensing physiological activity based on the inter-field interaction. According to the metamaterial physiological sensor and the use method, the problems that in the prior art, when physiological signals are monitored in a dynamic scene, sensitivity is low, and interference is prone to occurring are solved, and non-intrusive, comfortable and high-precision non-contact physiological signal monitoring is achieved.

The invention provides a photovoltaic power generation optimization method for a fishing-light complementary site and a related device. The method comprises the following steps: acquiring a photovoltaic panel sunlight angle, a water surface wind speed, a water surface wave height, a water depth, a photovoltaic panel core parameter, a reflector parameter and double-measuring-point actually-measured light intensity data; determining the initial receiving radiation quantity of the photovoltaic panel according to the sunlight angle of the photovoltaic panel, the core parameters of the photovoltaic panel, the parameters of the reflector and the actually measured light intensity data of the double measuring points; according to the water surface wind speed, the water surface wave height, the water depth, the double-measuring-point actually-measured light intensity data and the reflector parameters, the water surface correction reflection coefficient is determined; correcting the initial received radiation quantity of the photovoltaic panel by adopting the water surface correction reflection coefficient to obtain the actual received radiation quantity of the photovoltaic panel; and according to the actually received radiation quantity of the photovoltaic panel, the inclination angle of the photovoltaic panel is adjusted, and then the photovoltaic power generation process of the fishing-light complementary site is optimized. Excessive concentration of local radiation quantity caused by secondary reflection of sunlight through a water surface-reflector can be avoided, and generation of hot spots on the photovoltaic panel is inhibited.

The invention discloses a tunnel surrounding rock comprehensive elastic modulus testing method and system based on a surface wave method, and relates to the technical field of tunnel surrounding rock elastic model testing, and the method comprises the steps: collecting surface wave signals through detectors in a plurality of detection holes preset in a tunnel wall on the premise of exciting a seismic source signal; performing signal conversion on each preprocessed surface wave signal to obtain a plurality of first signals of a frequency domain type; performing smooth summation processing on the first signals subjected to the linear dynamic correction processing to obtain an output result; obtaining corresponding surface wave energy data through the output result, and obtaining a corresponding surface wave frequency dispersion curve based on extraction of the surface wave energy data; according to the surface wave dispersion curve, surface wave velocities of different depths in the surrounding rock are obtained through inversion, and the comprehensive elastic modulus of the tunnel surrounding rock is obtained through calculation based on the surface wave velocities; testing is carried out based on a surface wave method, drilling and coring are not needed, and the method has the advantages of high testing efficiency, low cost, small disturbance to surrounding rock and the like.

The invention provides a normal alignment algorithm of an ultrasonic probe, which belongs to the technical field of ultrasonic detection, and comprises the following steps of: automatically judging whether the current posture is vertical or not after a probe moves to a rough measurement point of a preset motion path by utilizing the distribution rule of ultrasonic time domain surface wave signal amplitude, and running a correction program when a deflection angle exists, so that the normal alignment of the ultrasonic probe is realized. And real-time waveform data is fed back to a motion actuator, and the actuator judges a result and guides the next motion, so that deflection correction of an unknown deflection angle is realized, a closed-loop control scheme of a control strategy and ultrasonic detection is constructed, and the ultrasonic thickness measurement precision and efficiency are effectively improved. The method is widely suitable for ultrasonic thickness measurement under industrial plane or curved surface coarse positioning.

The present disclosure relates to methods and apparatus for characterising an interaction between a stimulus and a liquid thin film. An aspect of the disclosure provides a spectroscopic ellipsometry apparatus for characterising an interaction between a stimulus and a liquid thin film, the apparatus comprising: a stimulator, configured to provide a stimulus to a liquid thin film disposed on a volume of liquid to generate a wave in the liquid thin film, the liquid thin film and the volume of liquid having an interface therebetween, light beam optics for illuminating an area of the liquid thin film with a light beam, the light beam having a first polarisation, and a light collector coupled to a detector for receiving the light beam after reflection by the liquid thin film, the light beam having a second polarisation after reflection by the liquid thin film; a wave measurement module coupled to the light collector and configured to provide surface wave data to characterise a Lucassen wave in the liquid thin film based on the second polarisation.

The invention relates to the technical field of pressure vessel health monitoring and nondestructive testing, in particular to an electromagnetic acoustic surface wave-based pressure vessel intergranular corrosion non-contact detection system, which comprises the following modules: a multi-field coupling electromagnetic acoustic surface wave detection module, which comprises a plurality of detection unit arrays, each detection unit comprises a magnetic biasing module and an impedance matching module and is used for generating a local magnetic field on the surface of the pressure vessel and optimizing signal excitation and receiving; and the signal acquisition and preprocessing module is used for acquiring the surface wave signal of the detection module and carrying out denoising, filtering, curved surface coupling difference correction and lift-off correction on the signal to obtain high-quality signal data. According to the method, non-contact quantitative detection of the intergranular corrosion of the pressure vessel is realized through multi-field coupling electromagnetic acoustic surface wave detection and microscopic and macroscopic mapping and inversion, so that the problem that early corrosion is difficult to quantify due to the fact that contact ultrasound is mostly adopted in traditional pressure vessel detection and grain boundary micro-damage cannot be effectively identified is solved.

The invention discloses a real-time rendering method and system for physical simulation water surface waves, and the method comprises the following steps: constructing a generative adversarial network, obtaining a wave vector and an environment parameter variable of the waves, inputting the environment parameter variable into the pre-constructed generative adversarial network, and calculating the height of the waves through a Tessendorf method; calculating wave displacement through Fourier transform and inverse transform in a frequency domain based on the wave vector; calculating the velocity complex amplitude of the corresponding wave based on the wave vector, introducing a micro-scale vortex velocity field based on a particle system, and calculating the wave velocity based on the velocity complex amplitude and the micro-scale vortex field; and based on the wave height, the wave displacement and the wave speed, performing water surface wave rendering by adopting multi-cascade dynamic. According to the method, the physical rationality and visual authenticity of water surface wave simulation are improved, and water body physical simulation is promoted to develop from visual driving to the fusion direction of physical driving and data driving.

The invention discloses a circumferential liquid film surface wave observation device and method based on a miniature high-speed camera. The circumferential liquid film surface wave observation device comprises a centrifugal nozzle, a laser, the high-speed miniature camera and a synchronizer, the centrifugal nozzle can spray a conical liquid film; the high-speed miniature camera is located at the central gas nucleus of the conical liquid film, and the optical axis coincides with the axis of the centrifugal nozzle; a narrow-band optical filter is arranged on the surface of an optical lens of the high-speed miniature camera; the laser can emit plane laser perpendicular to the axis of the centrifugal nozzle to the conical liquid film; wherein the wavelength of the planar laser is equal to the central wavelength of the narrow-band optical filter; and the synchronizer is respectively connected with the laser and the high-speed miniature camera. According to the method, a frozen instantaneous circumferential liquid film form without background interference can be obtained, a surface wave growth factor and a breaking critical criterion can be accurately quantified, and the development and evolution process of the circumferential surface wave of the liquid film is further obtained through high-speed shooting.

The invention relates to a method for calibrating an ultrasonic flowmeter, which is coupled to a pipe (1), for measuring a flow velocity or a volumetric flow rate of a fluid by means of two ultrasonic transducers (2, 3) spaced apart from one another, wherein the main directions of the ultrasonic transducers (2, 3) are oriented at an angle to one another in a symmetrical V shape. The aim of the invention is to provide an improved method which allows the ultrasonic flowmeter to be installed on a pipe with minimal effort, even by untrained personnel, without the accuracy of the measurement being impaired. For this purpose, the invention proposes the following steps: - ascertaining the propagation speed of an ultrasonic signal propagating through the pipe wall as a surface wave; - ascertaining the wall thickness of the pipe by determining the propagation time of an ultrasonic signal through the pipe wall; - ascertaining the inner diameter of the pipe by deriving it from the value of the adjusted angle and the distance of the ultrasonic transducers, - adjusting the angle to the ascertained pipe geometry by means of at least one motorized actuating drive (5) which sets the angle and an electronic calibration device (6) which interacts with the actuating drive (5).

The invention relates to the technical field of ocean engineering, in particular to a wind power single pile local scouring real-time detection method based on multi-frequency acoustic tomography, which comprises the following steps: S1, annularly arranging an acoustic sensor array on the section above the water surface of a pile body; s2, transmitting multi-frequency sound wave signals including low-frequency penetrating waves and high-frequency surface waves; s3, scattered wave signals reflected by the pile-seabed interface are collected, and low-frequency scattered waves and high-frequency scattered waves corresponding to the frequency in S2 are separated; s4, constructing a mud layer penetration acoustic tomography matrix and a surface topography acoustic tomography matrix; s5, three-dimensional data fusion is carried out, and a three-dimensional image of the scouring state of the seabed around the pile is generated; and S6, a scouring pit is positioned according to a sound wave propagation time delay sudden change area in the three-dimensional image of the scouring state. According to the method, the scouring state of the seabed around the wind power single pile foundation can be accurately monitored by combining the multi-frequency acoustic tomography technology and time delay abrupt change area detection.

A wave radar image inversion method based on a convolutional neural network, and the application thereof, which relate to the field of sea condition monitoring. A convolutional neural network autoencoder is used, and a training set generated by means of a simulation tool is input into the convolutional neural network autoencoder for supervised training, wherein an X-band radar image of an inversion region is an input of the training set, and a corresponding sea surface wave height map is an output of the training set, thereby obtaining a mapping relationship model therebetween. The convolutional neural network autoencoder comprises an encoder, fully connected layers and a decoder, wherein the encoder comprises five convolutional layers and five maximum pooling layers, the convolutional layers and the maximum pooling layers being alternately connected, the fully connected layers are two symmetric layers, and the decoder comprises five deconvolutional layers. Using a convolutional neural network deep learning algorithm achieves a better effect in restoring nonlinear components. Using an autoencoder technique can directly restore an X-band radar wave image to a real-time sea surface wave height map with a relatively small error, and can more comprehensively display sea condition information.

The invention relates to a physical condition embedded seismic surface wave intelligent inversion method and device and a medium, and the method comprises the steps: obtaining the seismic surface wave data of an active source or a passive source to be inverted, and carrying out the extraction through a frequency dispersion analysis method, and obtaining an observation frequency dispersion curve of the seismic surface wave data; constructing an initial shear wave velocity model, obtaining a theoretical frequency dispersion curve and a sensitivity matrix of the initial shear wave velocity model, and calculating physical condition embedding of the observation frequency dispersion curve based on the theoretical frequency dispersion curve and the sensitivity matrix of the theoretical frequency dispersion curve; based on an initial shear wave velocity model and physical condition embedding, an inversion model is used for iterative solution to obtain an inversion shear wave velocity model, and the device and the medium are used for implementing the method. Compared with the prior art, the method has the advantages that the problem that an initial model is easy to fall into a local minimum value due to manual selection is avoided, the inversion precision of the seismic surface waves is improved, the limitation of fixed input or output dimensions is eliminated, and the applicability of the inversion method in processing actual seismic surface wave data is remarkably improved.

The present invention is directed to an analytical method, using surface waves excited in a liquid system forming part of a sensor, to determine a property of a test substance. An aspect of the disclosure provides a method for controlling a sensor for determining a property of a test substance, the sensor having a sensitivity and dynamic range, the sensor comprising: a liquid system comprising: a bulk liquid phase carrying a thin film on the surface of the bulk liquid phase: wherein the thin film comprises a film material and wherein the thin film exhibits an electrical response to mechanical stress and vice versa wherein said response depends on the thermodynamic state of the liquid system, the sensor configured to: contact the surface of the liquid system with the test substance thereby to generate a surface wave on the liquid system: and, determine the property of the test substance based on parameters of the surface wave: wherein the method for controlling the sensor comprises: controlling the sensitivity by changing a thermodynamic parameter of the liquid system.

The application relates to a device and method for electrostatic induction and sound surface wave mask electrolytic machining, belonging to the electrolytic machining field. The pump, the liquid storage tank and the electrolytic tank are connected to realize electrolyte circulation. The various components in the electrolytic tank are riveted. The anode and cathode assemblies and the shielding induction electrode assembly are inserted into the electrolytic tank. The positive and negative poles of the power supply are connected with the anode and cathode plates in the anode and cathode assemblies respectively, and the workpiece arranged in the induction electrode assembly is arranged in the electric field between the anode and cathode plates. The piezoelectric ceramic is attached to the base plate of the induction electrode assembly, and the signal generator and the power amplifier are connected with the piezoelectric ceramic. Based on the device, the piezoelectric ceramic is connected with a megasonic driving voltage to generate a surface wave on the surface of the workpiece; the anode and cathode plates are connected with direct current, and the workpiece is arranged in the electric field formed by the anode and cathode plates, so that the surface to be machined of the workpiece is subjected to oxidation reaction, and the non-machining surface is subjected to reduction reaction, thereby realizing wireless induction machining of the workpiece. The application has the advantages of simple operation, re-distribution of the electric field, enhancement of mass transfer, improvement of mask electrolytic machining precision, arrangement of multiple workpieces in the electric field formed by the anode and cathode plates, and substantial improvement of mask electrolytic machining efficiency.

The invention discloses a ship channel modeling method for a marine unmanned aerial vehicle, and relates to the field of wireless channel modeling, and the method comprises the steps: obtaining the position information of an unmanned aerial vehicle and the position information of a ship; according to the position information of the unmanned aerial vehicle and the position information of the ship, constructing a three-dimensional model of the marine unmanned aerial vehicle to the ship channel; according to the three-dimensional coordinate system and the position relation, based on a sea surface fluctuation model and an unmanned aerial vehicle rotation model, coordinates of a receiving antenna and coordinates of a transmitting antenna are determined respectively; according to the three-dimensional coordinate system, the position relation, the propagation path, the coordinates of the receiving antenna and the coordinates of the transmitting antenna, determining the impulse response of the marine unmanned aerial vehicle to the ship channel; determining a space-time-frequency correlation function of the marine unmanned aerial vehicle to the ship channel; further carrying out modeling on the ship channel; according to the method, the non-stationary statistical characteristics of the marine unmanned aerial vehicle to the ship channel can be accurately described, and a theoretical basis is provided for design and performance optimization of an unmanned aerial vehicle auxiliary communication system in a complex marine environment.

The utility model provides a waveguide antenna structure with a frequency selective surface structure and a waveguide radar, and the structure comprises a waveguide antenna which is provided with a waveguide slot array and a frequency selective surface structure; the waveguide slot array is arranged on the waveguide antenna in a penetrating manner, and the frequency selective surface structures are distributed on the peripheral side of the waveguide antenna; the frequency selective surface structure comprises surface structure units, and the frequency selective surface structure is formed by arranging a plurality of surface structure units. According to the utility model, the frequency selective surface structure absorbs reflection between the top surface of the antenna and the antenna housing and reduces distortion of a directional diagram; surface waves can be reduced, space coupling between the antennas is reduced, and the isolation between the antennas is improved; the beam directivity can be adjusted, and beam performance specific directivity can be shaped.

The invention relates to an environment-friendly switch vacuum arc-extinguishing chamber contact temperature monitoring method and system based on surface acoustic wave array sensing and inversion, and belongs to the field of electrical monitoring. In order to solve the problem that in the prior art, non-intrusive and high-reliability monitoring of the contact temperature of the vacuum arc-extinguishing chamber is difficult to realize due to vacuum sealing and metal shielding, the technical scheme of the invention is as follows: an acoustic surface wave sensor array comprising three or more sensing nodes is constructed on the outer wall of the vacuum arc-extinguishing chamber, and the longitudinal temperature gradient distribution of the outer wall is captured in a lossless manner. A narrow-band flat-plate reader antenna is adopted to realize array signal parallel transmission with a high signal-to-noise ratio, and the steady-state temperature of an internal contact is accurately inverted through a pre-trained physical information neural network (PINN) model by utilizing multi-source data fusion and array characteristics. According to the method, a non-intrusive monitoring function from external sensing to internal deduction is realized, the problem that the temperature of the contact cannot be measured in a high-voltage closed environment is solved, and a key technical support is provided for safe operation of environment-friendly switch equipment.

The invention belongs to the technical field of pile foundation construction, and particularly relates to a scene sound analysis method for interaction of a pile and a karst cave in a construction process, which comprises the following steps of: step 1, high-precision karst cave form detection: arranging crossed measuring lines with the pile foundation as a center, the length of the measuring lines being more than or equal to 20m and the spacing being less than or equal to 1m, synchronously adopting a high-energy acceleration tamper and the impact energy being more than or equal to 50kJ, active source surface waves are excited, the impact frequency ranges from 2 Hz to 5 Hz, environment noise is collected to serve as passive source surface waves, a three-component detector array is used for receiving, and the sampling rate is larger than or equal to 500 Hz. According to the method for analyzing the interaction scene sound of the pile and the karst cave in the construction process, by setting the method for analyzing the interaction scene sound of the pile and the karst cave in the construction process, wave velocity changes in the vertical direction and the horizontal direction and anomalies in high-speed and low-speed areas are analyzed, and the thickness of a covering layer and the burying depth of bed rock are deduced; the development depth, the scale and the space distribution condition of the monolith and the karst caves are determined.

The invention relates to an antenna assembly and a vehicle. The antenna assembly comprises a dielectric body, a first antenna structure, a second antenna structure and a metal frame body. The projections of the plurality of second antenna structures on the dielectric body along the thickness direction of the dielectric body are arranged around the circumferential direction of the first antenna structure, the plurality of second antenna structures are rotationally symmetrical about the center of the first antenna structure, and each second antenna structure is coupled with the first antenna structure. The metal frame body is arranged around the periphery of the first antenna structure, and the metal frame body is connected with the dielectric body. The low-profile antenna structure is realized, the influence caused by the surface wave effect of the dielectric body is improved, the mutual coupling interference between double frequencies is reduced, and the antenna gain and the antenna bandwidth are improved. Besides, the metal frame body can restrain back lobe level energy, capacitance coupling is formed between the first antenna structure and the metal frame body, capacitance coupling is formed between the second antenna structure and the metal frame body, the antenna miniaturization design is further achieved, the overall size is reduced, and the installation space can be prevented from being limited.

The invention relates to the technical field of geophysical exploration, and discloses a common station pair coherent superposition enhancement method for active source seismic surface waves with a low signal-to-noise ratio. Comprising the following steps: generating a Green function according to a relative relationship between a seismic source position and a station pair: when the station pair is located at the same side of a seismic source, calculating the cross-correlation of seismic records of two stations in the station pair, and generating a cross-correlation Green function; when the station pair is located on the different side of the seismic source, the cross correlation between the seismic records of the two stations in the station pair and the seismic record of the reference station at the seismic source is calculated, then convolution calculation is carried out, and a convolution Green function is generated; frequency dispersion energy diagrams are respectively calculated based on the superposed cross-correlation Green function and convolution Green function; and superposing the two types of frequency dispersion energy diagrams to generate a final frequency dispersion diagram for extracting a frequency dispersion curve. According to the active source seismic surface wave signal co-station pair coherent superposition enhancement method provided by the invention, the surface wave signal-to-noise ratio and the frequency dispersion diagram quality are effectively improved on the premise that the data acquisition cost is not increased.

The invention discloses a beam forming antenna based on a holographic tensor impedance modulation metasurface and a design method thereof, and belongs to the technical field of microwave antennas. The antenna comprises a monopole feed source and a metasurface formed by a periodic array, wherein each tensor impedance unit adopts a three-layer structure comprising an upper slotted metal patch, a middle dielectric substrate and a lower metal grounding layer. A unit library of patch sizes and electromagnetic characteristics is constructed, tensor impedance distribution of each unit is calculated by adopting an iterative algorithm based on a holographic principle, and finally accurate matching with the unit library is realized. According to the invention, the surface wave can be efficiently converted into a specified target wave beam, high-gain and low-sidelobe dual-beam or flat-topped wave beam forming can be realized in a broadband, and meanwhile, the antenna has the advantages of low profile, easiness in integration and low cost, and can be widely applied to a modern wireless communication system.

The invention belongs to the field of earth exploration, and provides an urban underground collapse hidden danger area rapid detection system and method.The urban underground collapse hidden danger area rapid detection system comprises a miniature intelligent sensor array and a central processing unit, the miniature intelligent sensor array comprises a plurality of detection lines arranged side by side, and each detection line comprises a plurality of miniature intelligent sensors arranged at intervals; the adjacent micro intelligent sensors on the same detection line are connected through a towing cable; the distance between the adjacent micro intelligent sensors is adjustable; and the central processing unit is used for receiving the vibration data acquired by each miniature intelligent sensor, performing inversion on the vibration data by using a background noise surface wave imaging algorithm to obtain an underground transverse wave velocity structure model, and identifying a low-speed abnormal region as a collapse hidden danger region. According to the invention, efficient, accurate, wide-coverage and non-sensitive detection of urban underground collapse hidden dangers can be realized.