54 results about "Surface wave propagation" patented technology

The invention provides a switch cabinet contact temperature rise wireless sensing method and system based on surface acoustic wave resonance, and relates to the technical field of power system switch cabinet detection, and the method comprises the steps: calculating the real-time offset of a fundamental frequency and a third harmonic relative to a reference frequency, and obtaining the fundamental frequency offset and the third harmonic offset; in combination with the fundamental frequency offset and the equivalent acoustic impedance variable quantity of the oxide film, surface acoustic wave propagation path deformation caused by thermal expansion of the contact material is compensated by using a thermal-acoustic coupling partial differential equation, and the fundamental frequency net offset after temperature decoupling is obtained; sparse reconstruction is carried out on the temperature field of the contact area of the contact by adopting a compressed sensing algorithm, and three-dimensional temperature gradient distribution of the contact area of the contact is output; and inputting the three-dimensional temperature gradient distribution and historical time sequence data thereof into an intrinsic mode decomposition model for processing, and generating a dynamic self-adaptive early warning threshold value. The system has the advantages that passive, wireless, high-precision and full-space temperature rise monitoring is achieved, and intelligent operation and maintenance decision making of the switch cabinet is directly driven.

The invention relates to the technical field of physical acoustics, in particular to a saturated porous medium metasurface Portrait wave frequency dispersion relation calculation method and system, and the method comprises the following steps: obtaining expressions of solid skeleton displacement, fluid relative displacement, total stress, solid shear stress and pore pressure under the action of Portrait waves; obtaining an expression of a fluid displacement component and a fluid normal stress; obtaining an expression about the relative motion of the resonator; according to all the expressions, stress and displacement continuity boundary conditions are applied to the interface of the saturated porous medium and the fluid layer, a characteristic equation of frequency dispersion characteristics is obtained and solved, and a frequency dispersion curve is obtained. According to the method, the explicit frequency dispersion relation of the saturated porous medium metasurface portrait waves is provided, the calculation efficiency and prediction precision of complex interface wave propagation are improved, the optimal design of the metasurface resonator array can be guided, and a key theoretical tool and technical support are provided for design of high-performance acoustic functional devices and structures.

The invention provides a low-profile circularly polarized antenna unit for slot coupling feed and an array thereof, and the antenna unit employs a plurality of metal layers which are coaxially arranged, are sequentially stacked up and down and are separated through dielectric layers, thereby achieving the high integration of a feed network, a coupling structure and a radiation unit in the vertical direction of the antenna unit. Specifically, the parasitic patch and the radiation patch which are stacked and coupled up and down are adopted, so that the working bandwidth of the antenna unit is expanded; furthermore, the interference of a feed network on the radiation performance of the antenna is reduced through the separation of the upper metal ground and the lower metal ground, and meanwhile, two orthogonally distributed gap structures formed in the upper metal ground are matched with the microstrip transmission line to perform coupling feed, so that the circular polarization performance of the antenna unit is improved; in addition, periodically arranged metallized shielding through holes are formed in the edges of the antenna units, so that surface wave propagation and electromagnetic coupling between the units are effectively inhibited, and the performance stability of the antenna unit during large-angle scanning is improved while the low-profile characteristic of the antenna unit is ensured.

The invention provides a vector magnetic field detection method based on a surface acoustic wave magnetic field directivity model, and the method employs an external magnetic field to act on a magnetic sensitive film on a sound propagation path to generate a dynamic magnetoelastic coupling effect, modulates the propagation characteristics of surface acoustic waves, and carries out the decoupling of a sound signal, and obtains the magnetic field information. The response value of the sensor is influenced by the included angle between the direction of the external magnetic field and the anisotropic axis, so that the angle orientation of the sensor in the space and the size and direction of the magnetic field can be quantitatively calibrated by projecting the magnetic field to be measured in the space into a coordinate system of the sensor, and a surface acoustic wave magnetic field directivity model is constructed. The surface acoustic wave magnetic field sensing technology has the advantages of high sensitivity, quick response and the like, and the vector magnetic field detection method can realize the direction positioning function of a full-plane magnetic field and has important practical value in the application field of space vector magnetic field detection.

This application provides a surface acoustic wave (SAW) resonator and an electronic device. The SAW resonator includes interdigital transducers; along the SAW propagation direction, the duty cycle of the interdigital transducers gradually decreases, while the finger spacing gradually increases. This gradual decrease in duty cycle and increase in finger spacing along the SAW propagation direction helps reduce the excitation of stray modes and decrease the nonlinear harmonics generated by the coupling of the stray mode strain field E1 and the electrostatic field E2, effectively suppressing the generation of nonlinear harmonics and improving nonlinear effects.

This invention discloses a surface acoustic wave (SAW) device, comprising: a resonant filter element including multiple parallel resonators, one end of which is connected to at least one ground port; wherein at least two of the parallel resonators are connected to the same ground port, and the ground port connected to the at least two parallel resonators is a common ground port; and a packaging substrate located on one side of the resonant filter element; the packaging substrate includes a first substrate, which includes a common ground region and at least one independent cut-out region; the independent cut-out region is correspondingly disposed to at least one of the common ground ports and connected to the corresponding common ground port; the independent cut-out region is connected to the common ground region through a connecting portion, the extension direction of which is perpendicular to the SAW propagation direction of the SAW device. This invention improves the isolation performance of the device.

The utility model relates to a circular antenna array and a full-array antenna thereof, belongs to the technical field of satellite communication ground terminal antennas, and solves the problems of how to improve the broadband of the antenna array and reduce mutual coupling among array antenna units. The radiation patch on the third base layer generates radiation, and the parasitic patch on the first base layer introduces a new resonance point, so that the working bandwidth of the antenna is expanded; impedance matching in the working frequency band of the antenna array is carried out by adjusting the thickness of the second base layer; a metal wall structure increases the isolation degree between antenna units, inhibits surface wave propagation, improves the mutual coupling strength between the units, and improves the active standing wave performance of antenna array scanning.

The present invention relates to a manipulator end and method based on intelligent perception of ultrasonic surface wave contact stress, which is applicable to the real-time monitoring of local contact stress at the end of an industrial manipulator when grasping an object. It includes a special cylindrical or spherical end of the manipulator, ultrasonic transmitting and receiving probes, probe brackets, adjusting bolts and nuts, an ultrasonic transmitter-receiver, a data acquisition card, and a computer. Probe brackets are installed on the upper and lower planes of the manipulator end, and the adjusting bolts and nuts thereon are used to adjust and fix the positions of the probes; the probes, ultrasonic transmitter-receiver, data acquisition card, and computer are connected in sequence. During operation, the ultrasonic transmitter-receiver sends an electrical signal to excite the ultrasonic transmitting probe to generate surface waves; the surface waves propagate along the surface of the manipulator end, and the receiving probe receives the surface waves and converts them into electrical signals and sends them back to the ultrasonic receiver-transmitter; the data acquisition card samples and digitizes the emitted and received signals, and the computer realizes data storage and calculation analysis to obtain the change in the surface wave propagation time, realizing the real-time monitoring of the local contact stress at the end of the manipulator, enabling the originally cold industrial manipulator to have the ability to sense contact stress.

The application discloses a residual stress detection method based on chirp electromagnetic surface acoustic wave. Although the existing variable interval coil structure can expand the working frequency band of the sensor, the excitation ability of the low frequency component is limited, and it is difficult to meet the stress detection requirements of large thickness components. The electromagnetic acoustic sensor structure is designed, the width of the coil is continuously changed along the ultrasonic surface wave propagation direction, the wide frequency excitation of the chirp surface wave signal is realized, especially the excitation and propagation effect of the low frequency component is enhanced, so that the signal-to-noise ratio and detection accuracy after the signal matched filtering are significantly improved. The sensor utilizes the characteristics that the penetration depth of the ultrasonic surface wave changes with the frequency, realizes the layered detection of the multi-level residual stress in the material through the chirp signal, can cover multiple frequency ranges to adapt to components with different thicknesses, thereby avoiding the problem that the traditional fixed frequency or variable interval sensor needs to be frequently replaced. The method has high detection accuracy, wide detection range and high detection efficiency, and is suitable for nondestructive residual stress evaluation of metal components and engineering structure health monitoring.

A method for modeling a subterranean volume includes receiving seismic data comprising a signal, generating a semblance in the frequency-wavenumber domain for the seismic data, wherein the semblance represents a coherence of the signal in the frequency-wavenumber domain, extracting one or more wave energy modes in the semblance using a machine learning model trained to identify dispersion curves in the semblance based on a visible characteristic of the dispersion curves, and generating a model representing surface wave propagation based at least in part on the identified one or more wave energy modes.

The application provides a kind of pipeline medium pressure non-contact measurement method and device based on ultrasonic surface wave, the method is by fixing ultrasonic surface wave transceiver module TRA and ultrasonic surface wave transceiver module TRB on the pipeline to be detected, parallel to the central axis of the pipeline to be measured;Start the measurement program of industrial computer, and set the measurement threshold;Get the ultrasonic surface wave propagation time t0 in zero pressure state;The pressure value P of real-time pipeline medium is calculated by the pressure calculation formula based on thickness correction index, and the final pressure value is obtained after averaging;The application can realize high-precision and high-accuracy non-contact measurement of pipeline medium pressure, the detection resolution is greatly improved, and the ultrasonic surface wave only propagates in the surface layer of the pipe wall, the signal transmission loss is small, is not affected by the nature of the medium inside the pipeline, can effectively improve the accuracy of measurement results, can be used for electric vehicle related facility manufacturing, realizes high-accuracy non-contact measurement of pipeline fluid pressure measurement.

The invention provides a surface acoustic wave structure, a surface acoustic wave filter and communication equipment, and is characterized in that the lengths of at least part of first interdigital electrodes are set to be sequentially increased in the surface acoustic wave propagation direction, the increasing amplitudes are sequentially reduced, and the lengths of second interdigital electrodes are set to be sequentially reduced in the surface acoustic wave propagation direction; and the reduction amplitude is sequentially reduced, so that the excitation intensity of the surface acoustic waves of the interdigital transducer in each region in the surface acoustic wave propagation direction is non-linearly changed, and the excitation intensity is weakened in the region where a part of first interdigital electrodes arranged at the rear part in the surface acoustic wave propagation direction are located. The weakening can improve the near-band suppression capability of the surface acoustic wave filter, so that the resonant frequency burr phenomenon caused by transverse sound waves can be reduced or suppressed, namely, the resonant frequency splitting phenomenon is not easily caused. In addition, the surface acoustic wave structure provided by the invention does not need to be additionally provided with a structure for inhibiting a transverse mode, and is simple in preparation process, low in preparation cost and small in occupied area.

The present application relates to a surface acoustic wave device, a radio-frequency front-end module, and an electronic device. The surface acoustic wave device comprises a piezoelectric layer, and an interdigital electrode, which is provided on a first surface of the piezoelectric layer. The interdigital electrode comprises a plurality of electrode fingers. During the operation of the surface acoustic wave device, acoustic waves comprise surface acoustic waves and bulk acoustic waves, wherein the propagation direction of the surface acoustic waves is an X direction. A first characteristic thickness of the surface acoustic wave device is Ty, and the thickness of the piezoelectric layer is Dy, and the thickness of the piezoelectric layer and the first characteristic thickness meet the following conditions [equation I], wherein the piezoelectric layer comprises a piezoelectric crystal, and the value of the first characteristic thickness is determined on the basis of the centerline spacing between two adjacent electrode fingers, the bulk acoustic wave velocity of the piezoelectric crystal in the X direction, and an operating frequency. The thickness of the piezoelectric layer is defined by means of a first characteristic thickness, thereby preventing the acoustic functions of other structures from being affected by the excessive thickness of the piezoelectric layer, and thus improving the operation performance of the surface acoustic wave device.

The invention is suitable for the technical field of copper wire defect detection, and particularly relates to a copper wire defect detection method and equipment, and the method comprises the steps: obtaining an instantaneous phase difference and a temperature drift signal of a surface acoustic wave on the surface of a copper wire; wherein the surface acoustic wave is a standing wave type surface acoustic wave formed by interference on the surface of the copper wire through a double-pulse laser beam with a phase difference of 90 degrees; determining defect sensitive parameters based on the instantaneous phase difference and the temperature drift signal; wherein the defect sensitive parameter is used for representing the surface acoustic wave propagation characteristic change caused by defects in the copper wire; the defect equivalent depth of the copper wire is calculated based on the defect sensitive parameters, and the defect type of the copper wire is determined based on the defect sensitive parameters; wherein the defect equivalent depth is the average depth of all defects. According to the method, the precision and reliability of copper wire defect detection can be greatly improved, and interference or damage to the copper wire in the detection process can be avoided.

The application discloses a kind of effective Fennel reflection coefficient calculation method based on sea wave spectrometer, first by least square fitting anisotropic quasi-speculum scattering formula, the slope variance component of observation azimuth is obtained;The variation law of the slope variance component with azimuth is fitted with azimuth cosine function, to obtain the total slope variance of the detected sea surface, slope variance component fluctuation rate and sea surface wave propagation direction;Then by the slope variance component along the wave propagation direction and total slope variance, the distribution of the slope variance component perpendicular to the detection azimuth with observation azimuth is obtained;Finally, by calculating the non-standardized correlation coefficient between observation azimuth and the slope variance perpendicular to observation azimuth angle, the 0 degree effective Fennel reflection coefficient of different incident angle beams can be obtained according to quasi-speculum scattering formula, and the effective Fennel reflection coefficient of Ku band at 0 degree incident angle can be obtained by averaging the results of each beam with wind speed.

The invention discloses an uncalibrated stress measurement method based on ultrasonic surface wave and incremental deformation mechanics and a related device, and relates to the technical field of ultrasonic nondestructive testing. The method comprises the following steps: exciting an ultrasonic surface wave signal through an excitation sensor arranged on the surface of a test piece to be detected; acquiring an ultrasonic surface wave time domain signal in a stress state by a receiving sensor; the wave velocity is calculated by combining the distance between the sensors and the propagation time, and then the stress value on the detection path is determined according to an ultrasonic surface wave velocity-stress formula. The wave velocity-stress formula is derived from a control equation established based on an incremental deformation mechanics theory and surface wave propagation characteristics, the dependence on a high-order elastic constant in the prior art is avoided from the source, zero-stress test piece calibration is not needed, and the constraint of a calibration result is thoroughly got rid of. According to the method, the advantages of no damage, no radiation and simple and convenient equipment of ultrasonic detection are continued, the applicability and the generalization performance are remarkably improved, and the absolute stress measurement on the surface and the near surface of the test piece can be accurately realized.

Apparatus provide plasma to a processing volume of a chamber. The Apparatus may comprise a plurality of plasma sources, each with at least a dielectric tube inlet which is at least partially surrounded by a conductive tube which is configured to be connected to RF power to generate plasma and a gas inlet positioned opposite the dielectric tube inlet for a process gas and a dielectric tube directly connected to each of the plurality of plasma sources where the dielectric tube is configured to at least partially contain plasma generated by the plurality of plasma sources and to release radicals generated in the plasma via holes in the dielectric tube.

This invention provides an adjustable notch filter based on a ridge waveguide SSPP structure, relating to the field of wireless communication technology. By introducing independent planar adjustable notch units into the ridge waveguide SSPP structure, the notch frequency can be continuously adjusted without compromising the surface wave propagation characteristics and frequency-selective transmission response of the SSPP. The SSPP structure is formed by periodically etching multiple grooves along the propagation direction on a metal ridge, with continuous portions of the metal ridge maintained between adjacent grooves. These periodic grooves modulate the dispersion characteristics of the electromagnetic field within the ridge waveguide, enabling the ridge waveguide to support equivalent surface plasmon wave propagation, thereby forming a stable frequency-selective transmission response within a predetermined frequency range. The planar adjustable notch unit constructs a main transmission path and a secondary transmission path, utilizing the destructive interference of the two paths at a specific frequency to create a notch effect. Simultaneously, by changing the equivalent capacitance value of the varactor diode, the notch frequency can be continuously adjusted within the predetermined frequency range.

According to the intelligent sensing caulking sealing structure and the runway pavement health state monitoring method provided by the invention, the prefabricated sensing rubber strip with the modulus gradient transition embedding material is arranged in the runway shoulder caulking, so that tight coupling and cooperative deformation between the sensing optical cable and the caulking glue made of a silicone material are realized; the problems of modulus mismatch, interface stripping, optical cable bounce and the like are effectively solved, and stable and high-fidelity acquisition of vibration signals is ensured; according to the monitoring method, the system identification technology of center line excitation and runway shoulder response is utilized, the surface wave propagation model and the regularization reconstruction algorithm are combined, the runway center line vibration state is inversed in a high-precision mode from runway shoulder signals, propagation attenuation and time delay are compensated, the monitored space coverage capacity and signal restoration precision are remarkably improved, and the monitoring precision is improved. The low-influence, wide-coverage and continuous real-time monitoring of the stock runway is realized, and finally a more reliable and efficient technical scheme is provided for runway surface health state evaluation and operation safety guarantee.

The invention relates to a surface acoustic wave device, a radio frequency front-end module and electronic equipment. The surface acoustic wave device comprises a piezoelectric layer and an interdigital electrode arranged on the first surface of the piezoelectric layer, wherein the interdigital electrode comprises a plurality of electrode fingers; when the surface acoustic wave device works, acoustic waves comprise surface acoustic waves and bulk waves, and the propagation direction of the surface acoustic waves is the X direction; the first characteristic thickness of the surface acoustic wave device is the thickness of the piezoelectric layer, and the thickness of the piezoelectric layer and the first characteristic thickness meet the condition; wherein the piezoelectric layer comprises a piezoelectric crystal, and the size of the first characteristic thickness is determined according to the midline distance between two adjacent electrode fingers, the bulk wave sound velocity of the piezoelectric crystal in the X direction and the working frequency of the piezoelectric crystal. The thickness of the piezoelectric layer is limited through the first characteristic thickness, so that the influence on the acoustic function of other structures due to the too thick piezoelectric layer is avoided, and the working performance of the surface acoustic wave device is improved.

The application provides a PCB copper cladding layer thickness online monitoring method based on surface acoustic wave resonance, relates to the technical field of electronic manufacturing, and comprises the following steps: step 1, design and preparation of a surface acoustic wave resonator: a stepped interdigital electrode structure or an asymmetric interdigital electrode array is prepared on the surface of a piezoelectric substrate of the surface acoustic wave resonator, the geometric parameters of the interdigital electrode are designed according to a target copper cladding layer thickness range and surface acoustic wave propagation characteristics, and the width, spacing and logarithm of the interdigital electrode are adjusted so that the working frequency range of the surface acoustic wave resonator covers the frequency shift range caused by the change of the copper cladding layer thickness; step 2, sensor installation and signal coupling; step 3, resonance frequency shift analysis and thickness mapping; and step 4, online feedback and process regulation. Through the precisely designed and optimized surface acoustic wave resonator and the efficient signal processing algorithm, accurate PCB copper cladding layer thickness monitoring can be provided in a complex environment.

The invention provides an electromagnetic surface wave transmission method based on wave-absorbing coating damage three-dimensional reconstruction, and belongs to the technical field of measurement, and the method comprises the following steps: carrying out microwave heating treatment on a damaged wave-absorbing coating sample, and carrying out computer treatment to obtain a surface temperature cloud picture of the sample; extracting an area of which the surface temperature of the wave-absorbing coating is higher than the test environment temperature from the surface temperature cloud picture; performing triangular surface grid division on the extracted region, and combining all triangular volume elements to realize three-dimensional reconstruction of the damaged region of the wave-absorbing coating; constructing a surface wave propagation method based on a dispersion equation; a dispersion equation is utilized to analyze transmission of surface waves in the three-dimensional reconstruction model of the damaged area of the wave-absorbing coating, the influence of the thickness of a triangular voxel and electromagnetic parameters of a combined model of the triangular voxel on a surface wave attenuation constant is discussed, and a surface wave attenuation constant model based on three-dimensional reconstruction of the damaged area of the wave-absorbing coating is constructed. The method provides a theoretical basis for damage evaluation of the wave-absorbing coating of the aircraft.

This invention relates to a reconfigurable metasurface for dynamically controlling the topological characteristics of electromagnetic polaritons. The invention comprises a basic functional unit combined with a varactor diode periodically extended in a two-dimensional plane. The basic functional unit includes a single-layer dielectric, two layers of metal, and metallized vias. By changing the applied bias voltage, reconfigurable topological transmission of the polariton dispersion topology can be achieved, from open ellipses to straight lines, hyperbolas, and circles. Utilizing the wavefront characteristics under different dispersion topologies, broadband field channelization, dynamic focusing, and reconfigurable polariton circuit design can be realized. This invention further improves the flexibility of surface wave propagation and guidance manipulation, possessing advantages such as low dimensionality, continuous controllability, and high-speed response. It is beneficial for the integration of electromagnetic components in modern near-field information processing systems, the design of photonic integrated circuits and multifunctional programmable plasmon polariton devices, and has broad application prospects in near-field sensing, positioning, high-resolution imaging, and energy reuse.

The present invention discloses a reconfigurable metasurface for flexibly manipulating non-diffraction surface waves. The metasurface is composed of a passive gradient refractive index unit array and an electrically adjustable gradient refractive index unit array. Unlike existing non-diffraction surface wave generators with fixed structures and functions, the electrically adjustable gradient refractive index unit in the present invention integrates electrically adjustable elements. Through a clever control circuit design, a voltage control module can be used to change the refractive index distribution of the electrically adjustable gradient refractive index unit array in real time, achieving the transition from cylindrical wavefront surface waves to non-diffraction surface waves, and enabling dynamic control of the propagation direction and non-diffraction distance of the non-diffraction surface waves. This invention is expected to be applied to fields such as surface wave energy transmission, short-range communications, and wireless charging.

The invention provides a multi-parameter surface acoustic wave sensor based on microstructure regulation and control, and relates to the technical field of surface acoustic wave sensors, the sensor comprises a gradient nano-composite structure, a periodic microporous structure, a multi-parameter sensing unit and antenna integrated module, and components and orientation gradient structures of a gradient nano-composite layer, the high temperature resistance and acoustic performance of the material are improved; the periodic microporous structure disperses thermal stress, regulates and controls the sound field, and reduces the propagation attenuation of the surface acoustic wave. The multi-parameter sensing unit integrates a temperature sensing unit, a pressure sensing unit and a strain sensing unit, accurate monitoring and decoupling are achieved, and the measurement error is small. The flexible substrate is matched with the curved surface of the special-shaped component for installation, the antenna integrated module is high in signal transmission efficiency and good in stability at high temperature after being optimized, the manufacturing method adopts mature MEMS processes such as photoetching and etching, compatibility is high, batch production is easy, the problem of multi-parameter monitoring of the special-shaped component in the severe environment is effectively solved, and wide application prospects are achieved.

The invention provides a surface acoustic wave gas sensor and a manufacturing method, and belongs to the technical field of sensors. The sensor comprises a piezoelectric substrate, four groups of interdigital transducers and four groups of reflecting gratings, wherein the four groups of interdigital transducers and the four groups of reflecting gratings are formed on the piezoelectric substrate; wherein the surface of the piezoelectric substrate between the two groups of interdigital transducers is covered with a gas sensitive film, and the two groups of reflecting gratings, the two groups of interdigital transducers, the gas sensitive film and the piezoelectric substrate form a detection channel; the other two groups of interdigital transducers, the other two groups of reflecting gratings and the piezoelectric substrate form a reference channel; and an isolation groove is formed in the piezoelectric substrate between the detection channel and the reference channel. According to the method, the difference value of the propagation delay time of the surface acoustic waves of the detection channel and the reference channel is calculated, and the concentration of the target gas is calculated based on the difference value, so that differential compensation of common-mode interference is realized; the surface acoustic wave of the detection channel is prevented from spreading to the reference channel through the isolation groove, the coupling interference between the detection channel and the reference channel is reduced, and the cross interference rejection ratio is increased.

This invention discloses a method for analyzing the propagation characteristics of multilayer surface acoustic waves (SAWs), comprising the following steps: obtaining material parameters of each layer and substrate material, including elastic coefficient, piezoelectric coefficient, dielectric constant, and density; setting structural parameters of each layer; performing dimensional analysis-based normalization on the parameters; calculating the coefficient matrix, transmission matrix, substrate mode matrix, and system matrix; applying boundary conditions to the top layer surface to obtain the system matrix after applying the boundary conditions and calculating the determinant value; performing a velocity scan and repeating the above steps to obtain the relationship curve between velocity and the determinant value of the boundary condition system matrix; finding the zero point of the relationship curve, the velocity corresponding to the zero point being the SAW phase velocity; calculating the electrical coupling coefficient; calculating state vector, mode shape, penetration depth, and other indicators; modifying structural parameters or temperature, and repeating the above steps to obtain the relationship between SAW propagation characteristics and the changes of each parameter.

The invention provides a non-contact measurement method and device for pressure of a medium in a pipeline based on ultrasonic surface waves, and the method comprises the steps: fixing an ultrasonic surface wave receiving and transmitting module TRA and an ultrasonic surface wave receiving and transmitting module TRB on a detected pipeline, and enabling the TRA and the TRB to be parallel to the central axis of the detected pipeline; starting a measurement program of the industrial personal computer, and setting a measurement threshold value; the ultrasonic surface wave propagation time t0 in the zero-pressure state is obtained; calculating to obtain a real-time pressure value P of the medium in the pipeline according to a pressure calculation formula based on the thickness correction index, and averaging to obtain a final pressure value; non-contact measurement of the pressure of the medium in the pipeline can be realized with high precision and high accuracy, the detection resolution is greatly improved, the ultrasonic surface wave is only propagated on the surface layer of the pipe wall, the signal transmission loss is small, the influence of the property of the medium in the pipeline is avoided, the accuracy of the measurement result can be effectively improved, and the method can be applied to manufacturing of related facilities of electric automobiles. And high-accuracy non-contact measurement of the pressure of the fluid in the pipeline is realized.

The application provides an electromagnetic surface wave transmission method based on three-dimensional reconstruction of damage of a wave-absorbing coating, and belongs to the technical field of measurement, and comprises the following steps: microwave heating treatment is performed on a wave-absorbing coating sample with damage, and a surface temperature cloud chart of the sample is obtained through computer processing; a region with a surface temperature of the wave-absorbing coating higher than a test environment temperature is extracted from the surface temperature cloud chart; the extracted region is subjected to triangular face mesh division, and all triangular elements are combined to realize three-dimensional reconstruction of the damage region of the wave-absorbing coating; a surface wave propagation method based on a dispersion equation is constructed; the transmission of surface waves in the three-dimensional reconstruction model of the damage region of the wave-absorbing coating is analyzed by using the dispersion equation, the influence of the thickness of the triangular element and the electromagnetic parameters of the combined model on a surface wave attenuation constant is discussed, and a surface wave attenuation constant model based on three-dimensional reconstruction of damage of the wave-absorbing coating is constructed. The application provides a theoretical basis for damage evaluation of a wave-absorbing coating of an aircraft.

Apparatus provide plasma to a processing volume of a chamber. The Apparatus may comprise a plurality of plasma sources, each with at least a dielectric tube inlet which is at least partially surrounded by a conductive tube which is configured to be connected to RF power to generate plasma and a gas inlet positioned opposite the dielectric tube inlet for a process gas and a dielectric tube directly connected to each of the plurality of plasma sources where the dielectric tube is configured to at least partially contain plasma generated by the plurality of plasma sources and to release radicals generated in the plasma via holes in the dielectric tube.