301 results about "Acoustical impedance" patented technology

The invention relates to the technical field of crack image analysis, in particular to a building crack width measuring method based on image analysis, which comprises the following steps of: acquiring an autofluorescence attenuation image of a building surface under ultraviolet excitation, and generating a crack response coefficient matrix according to a material aging degree; driving micro-area pulse thermal imaging based on the crack response coefficient matrix, and extracting a heat conduction abnormal boundary as a crack physical edge; surface attachment interference is eliminated through an edge acoustic impedance matching model, and the real width value of the crack is calculated under a material intrinsic coordinate system. According to the method, the normal width of the crack is measured through uniform point selection in the main axis direction, the measured value is subjected to weighted fusion in combination with the local acoustic impedance matching weight, the obtained width result can better reflect the actual structural integrity and elastic continuity of the crack, geometric quantities are provided, and the local damage degree is reflected; the method is suitable for subsequent structure analysis and safety evaluation.

The invention discloses a method, a system, equipment and a medium based on a multi-composite ultrasonic penetration technology, and the method comprises the steps: generating high-frequency fundamental ultrasonic waves through a piezoelectric transducer array, and adjusting the frequency range to match the acoustic impedance characteristic of target soil; first, second and third harmonics are generated through the induction of a nonlinear medium in the fundamental wave propagation process, the phases of the harmonics are adjusted to realize coherent superposition, and the fundamental wave and the first, second and third harmonics are guided into a composite waveguide device for focusing and delay compensation to form a high-energy composite wave beam; a pulse interval is adjusted by adopting an intermittent emission strategy so as to inhibit energy attenuation in the soil; reflected wave spectrum components are monitored through an embedded acoustic sensor array, and driving parameters are dynamically adjusted; and residual ultrasonic energy is captured and fed back to a driving circuit to form a closed-loop energy utilization system. By integrating multi-order harmonic resonance and a dynamic frequency tuning technology, efficient transmission and deep penetration of ultrasonic energy in a complex medium are realized.

The invention provides a textile cloth defect real-time detection method and system based on multi-modal feature fusion, and the method comprises the steps: collecting visual image data, infrared thermal imaging data and ultrasonic acoustic data of textile cloth through a multi-sensor array, and forming multi-modal input; performing time sequence alignment and noise filtering preprocessing on the multi-modal data to eliminate motion artifacts and environmental interference; a parallel feature extraction module is used for extracting texture features from the visual data, extracting temperature distribution features from the thermal imaging data and extracting acoustic impedance features from the acoustic data. By deeply fusing complementary information of three modes of vision, thermal imaging and ultrasonic wave, the detection capability is improved, the vision mode captures surface texture details, the thermal imaging mode reveals thermodynamic anomalies related to friction and materials, the ultrasonic wave mode perceives subcutaneous structure defects, hidden flaws which cannot be recognized by a single mode can be found, and the detection efficiency is improved. Therefore, the omission ratio is greatly reduced, and flaw types are distinguished more accurately.

This invention discloses a method and apparatus for cementing quality inspection based on ultrasonic Lamb waves. The method includes: acquiring a first ultrasonic Lamb wave signal received by a first receiver and a second ultrasonic Lamb wave signal received by a second receiver; calculating the first wave energy of a zero-order symmetric Lamb wave within a first time window of the first ultrasonic Lamb wave signal, and calculating the second wave energy of a zero-order symmetric Lamb wave within a second time window of the second ultrasonic Lamb wave signal; calculating the attenuation rate of the zero-order symmetric Lamb wave based on the first wave energy, the second wave energy, a first distance, and a second distance; comparing the attenuation rate with a pre-generated attenuation rate threshold, and determining the external medium properties based on the comparison result. This approach improves the accuracy of cementing quality inspection; and it allows for independent cementing quality evaluation without the need for combined acoustic impedance information, simplifying the cementing quality inspection process and improving its efficiency.

The invention discloses a micro-scale tin soldering device and method for ultrasonic laser composite energy field coordinated regulation and control. The micro-scale tin soldering device comprises a coordinated energy output module, a multi-physical field monitoring module, a wire feeding module, an intelligent regulation and control system and a motion platform, and a workpiece to be welded is arranged on the motion platform; the collaborative energy output module comprises a laser unit, an ultrasonic vibration unit and a focusable focus lens, the ultrasonic vibration unit comprises an ultrasonic generator, and the multi-physical field monitoring module comprises an infrared thermometer, a high-speed holographic imaging system and an acoustic impedance sensor; the high-speed holographic imaging system is used for recording brazing filler metal molten pool flowing and IMC nucleation dynamic states; the acoustic impedance sensor monitors the ultrasonic energy transmission efficiency; the intelligent regulation and control system is electrically connected with the multi-physics field monitoring module, and a multi-physics field coupling prediction model based on an LSTM neural network is arranged in the intelligent regulation and control system. According to the technical scheme, the structural design is reasonable, the energy field coupling efficiency is high, the material adaptability is high, the structure performance is controllable, the defect rate is remarkably reduced, and practicability is good.

The invention discloses a rotator cuff injury impact test method based on sensor data analysis, and relates to the technical field of intelligent medical equipment, and the method comprises the steps: inputting a joint contracture data set into a generative adversarial network model, carrying out pressure propagation mode analysis through a three-dimensional convolution layer, carrying out energy hot spot aggregation through an attention mechanism layer, and carrying out pressure propagation mode analysis through a three-dimensional convolution layer; the method comprises the following steps: generating a pressure field comprehensive vector of a contracture joint, extracting gradient amplitude and energy density characteristics in the pressure field comprehensive vector, performing neighborhood smoothing through Gaussian average filtering, obtaining an acoustic impedance value matrix, synchronously performing spatial continuous mapping, obtaining an acoustic impedance distribution diagram, and obtaining an acoustic impedance value of the contracture joint according to the acoustic impedance distribution diagram. And performing dynamic compensation on the pressure field comprehensive vector through an acoustic transmission equation to obtain a corrected pressure field comprehensive vector, and converting the corrected pressure field comprehensive vector into an impact control signal through a PID (Proportion Integration Differentiation) controller. According to the invention, through the generative adversarial network model and the PID controller, the multi-physical field data of the joint contracture area can be integrated, and the frequency and pulse width of the shock wave therapeutic apparatus can be adjusted.

The invention belongs to the technical field of biomedical materials, and particularly relates to preparation of a hydrogel ultrasonic coupling patch for long-term stable continuous monitoring. According to the patch, an interpenetrating double-network structure system is formed by an alginate component and a polyacrylic acid component through intermolecular interaction, and the patch has excellent adhesion performance and mechanical performance. Compared with the prior art, by optimizing the components and the preparation process, the obtained hydrogel patch has the following advantages that the excellent acoustic impedance matching characteristic is achieved, and high-fidelity transmission of ultrasonic signals is ensured; the tissue adhesion is strong, and long-term stable attachment can be realized; good mechanical stability and durability are achieved, and the method is suitable for continuous monitoring application. The product effectively solves the technical problems that the traditional liquid coupling agent is easy to lose, the solid coupling patch is insufficient in adhesion and the like, and has important application value in the fields of medical ultrasonic diagnosis and long-term monitoring.

The invention provides a cell acoustic characteristic parameter estimation method and system based on a full-connection neural network and a computer medium, and relates to the technical field of biomedical engineering and micro-nano operation, and the method comprises the steps: constructing a three-layer spherical shell model of a target cell, defining the radius, density and sound velocity of each layer and a surrounding medium, and constructing a three-layer spherical shell model of the target cell; the acoustic impedance and the wave number of each layer are calculated; obtaining a transducer driving parameter, a displacement speed of the cell or equivalent particle solid sphere particle, and physical parameters of the cell and a medium; inputting the input feature data into a pre-trained full-connection neural network model to output acoustic characteristic parameters such as a scattering coefficient and an internal refraction coefficient; and calculating acoustic radiation force based on the acoustic characteristic parameters to realize dynamic control. Based on the full-connection neural network and the three-layer spherical shell model, the cell acoustic parameters are efficiently and accurately estimated, the problems that a traditional method is complex in calculation and insufficient in precision are solved, and accurate operation of the acoustic tweezers on the cells is achieved.

The invention provides a shared excitation source ultrasonic and infrared thermal imaging integrated detection method and system, and the method comprises the steps: applying a shared excitation source to a to-be-detected object, synchronously collecting a multi-channel ultrasonic echo signal and an infrared thermal imaging image, dividing the to-be-detected object into a plurality of target regions, and calculating the frequency band ultrasonic attenuation coefficient and acoustic impedance of each region, further obtaining a densification value; after a heat flow response feature map is extracted from an infrared image, adaptive partitioning is carried out on multi-modal data according to the spatial gradient of a densified value and a heat flow response energy accumulation area, and a plurality of data analysis subsets are formed. For each subset, constructing a local joint dictionary according to the densification value and the heat flow feature of the subset; and performing joint sparse representation on the ultrasonic and infrared features in the subsets by using the dictionary to obtain a group of cross-modal fusion coefficients, accurately determining defect information in the object to be detected based on the fusion coefficients and a defect identification model, and generating a defect distribution diagram.

The invention provides a breast cancer molecular subtype recognition and prediction method and system based on an ultrasonic image, and the method comprises the steps: carrying out the feature fusion preprocessing of a breast ultrasonic image based on acoustic impedance difference, and obtaining a standardized ultrasonic image; dividing the image into fan-shaped regions based on the radial fiber structure of the mammary gland, and dynamically adjusting the window size according to tissue characteristics to carry out adaptive window segmentation to obtain a window set carrying anatomical structure position information; inputting the window set into a pre-trained cross window Transform model for feature extraction, and analyzing a feature association mode between the windows through a cross window attention mechanism to obtain a multi-dimensional ultrasonic feature vector; and inputting the feature vector into a classifier for molecular subtype classification prediction to obtain a breast cancer molecular subtype identification prediction result. According to the method, through adaptive window segmentation, breast anatomical structure information is utilized, local and global feature association is captured through a cross window attention mechanism, and the prediction accuracy is improved.

The invention discloses a surface acoustic wave resonator and a filter. The surface acoustic wave resonator comprises a substrate; the interdigital transducer is positioned on one side of the substrate; the reflecting grating and the interdigital transducer are arranged on the same layer, and the reflecting grating is located on the two sides of the interdigital transducer in the first direction; the plurality of reflecting gratings are arranged along a first direction and extend along a second direction; in the first direction, a reflecting grating gap is formed between any two adjacent reflecting gratings; the first direction and the second direction intersect and are parallel to the plane where the substrate is located; the orthographic projection of the acoustic impedance structure on the plane where the substrate is located is at least overlapped with the orthographic projection of the reflecting grating gap on the plane where the substrate is located; the acoustic impedance of the acoustic impedance structure is different from the acoustic impedance of the reflecting grating. By adopting the technical means, the acoustic impedance structure is arranged, and the acoustic impedance of the acoustic impedance structure is different from that of the reflecting grating, so that a stray mode in the resonator can be inhibited, and the performance of the surface acoustic wave resonator is further improved.

The invention discloses a solid ultrasonic gel patch as well as a preparation method and application thereof, and belongs to the technical field of medical chemistry. The solid ultrasonic gel patch is prepared from an acrylamide monomer, polyvinyl alcohol, sodium polyacrylate, sodium carboxymethyl cellulose, nano silicon dioxide, propylene glycol, glycerol, acrylic acid, triethanolamine, a cross-linking agent, an initiator and water according to a specific ratio. The prepared solid ultrasonic gel patch is highly matched with human soft tissue in acoustic impedance (about 1.62-1.63 * 10 < 6 > Pa.s / m), low in acoustic attenuation coefficient (less than or equal to 0.034 dB / (cm.MHz)), moderate in skin adhesion, excellent in flexibility and moisture retention, capable of solving the problems that a traditional ultrasonic coupling agent is inconvenient to use, easy to dry, poor in experience and the like, and suitable for acoustic wave conduction in ultrasonic examination and treatment.

The invention discloses a method for inverting the velocity of a cementing medium after casing based on ultrasonic Lamb waves, and relates to the field of geophysical logging. According to the method, ultrasonic Lamb wave logging and ultrasonic pulse reflection logging are carried out at all depth points through a post-casing scanning imaging logging instrument, waveform records at all the depth points are obtained, the thickness of a casing in the specified direction at all the depth points and acoustic impedance of a post-casing cementing medium are calculated in an inversion mode, and then the thickness of the casing in the specified direction at all the depth points and the acoustic impedance of the post-casing cementing medium are calculated on the basis of the ultrasonic Lamb wave logging waveform records. For each specified orientation of each depth point, Fourier transform is carried out on the full waveform of the near-bending Lamb wave and the full waveform of the far-bending Lamb wave, the phase difference of the far-bending Lamb wave and the far-bending Lamb wave is calculated, group delay processing is carried out, the working frequency band of the imaging logging instrument is scanned after combination, and the phase difference of the far-bending Lamb wave and the near-bending Lamb wave is calculated; and frequency values corresponding to the minimum values of the group delays at all the directions of all the depth points are obtained, and after a frequency set is obtained, the wave velocity and the medium type of the cementing medium after casing are determined according to the frequency values at all the directions in the frequency set, the frequency number of the minimum values and the acoustic impedance value.

The invention provides an MEMS heart sound and electrocardio detection system, method and equipment, and relates to the technical field of medical instruments, the MEMS heart sound and electrocardio detection system comprises a bionic cilium heart sound sensor, an electrocardio acquisition circuit and a signal fusion model; the bionic cilia heart sound sensor comprises hollow bullet type bionic cilia and a cantilever beam microstructure; the hollow bullet type bionic cilia and the cantilever beam microstructure are mechanically coupled, and the cantilever beam microstructure comprises a Wheatstone bridge formed by arranging a plurality of piezoresistors and is used for collecting heart sound signals; the electrocardio acquisition circuit and the bionic cilium heart sound sensor are packaged in an acoustic impedance matching mode, and the electrocardio acquisition circuit comprises an electrocardio acquisition electrode plate, a power supply voltage stabilization module, an instrument amplification module, a band-pass filtering module and a notch filter and is used for acquiring and conditioning electrocardio signals; the signal fusion model comprises a Resnet18 feature extractor, an encoder and a mutual cross attention mechanism, and is used for performing feature extraction, linear transformation and feature deep fusion on the collected electrocardiosignals and electrocardiosignals and outputting a signal classification result.

The invention discloses a forest biomass nondestructive testing device and method in forestry carbon sink measurement, and relates to the technical field of forestry resource monitoring and carbon sink evaluation, the device comprises a multi-mode sensing unit, an underground biomass monitoring module and a data processing unit, the multi-mode sensing unit collects forest stand data through cooperation of a microwave radar, a laser radar and a hyperspectral imaging assembly. The underground biomass monitoring module collects acoustic impedance data of a root system; the data processing unit comprises an environment feature recognition module, a dynamic calibration engine, an organ recognition unit, a dynamic carbon distribution unit and a carbon sink metering module, the method comprises the following steps: cooperatively acquiring data through an air base and a foundation, analyzing environment features, dynamically calibrating, segmenting organs and generating a carbon distribution coefficient, and finally calculating the carbon sink amount of a single tree according to a formula. According to the invention, non-contact multi-parameter synchronous acquisition is realized, environmental changes are adapted through dynamic calibration, accurate metering is realized by means of organ-level carbon distribution, and the precision and reliability of forestry carbon sink metering are improved.

The invention discloses a modeling method of an acoustic impedance calculation model for an ablated surface of a carbon-based composite material, and belongs to the field of aerospace. Aiming at the defects of a modeling method of an existing Fedorov acoustic impedance model on a carbon-based fiber material, heat flow resistance and heat characteristic length are introduced on the basis of a formula of an original impedance model, and a dimensionless complex dynamic compressibility coefficient is modified, so that the Fedorov acoustic impedance model is developed from a four-non-acoustic-parameter impedance model to a six-non-acoustic-parameter impedance model. An impedance model used for correction is a JCAL acoustic impedance model, the impedance model is often used in the acoustics field to predict the surface acoustic impedance of the irregular fiber material, and then the prediction precision of the original impedance model on the surface acoustic impedance of the non-uniformly distributed carbon-based fiber material is improved. And fitting the improved impedance model into a test result of an impedance tube experiment through parameter inversion to obtain non-acoustic parameter data suitable for the ablated carbon-based composite material, and obtaining an improved acoustic impedance model suitable for the carbon-based composite material.

The invention provides a quantitative analysis method and system for an in-situ leaching uranium mining flow field. According to the method, the historical flow and pressure time sequence data of the liquid injection pipeline are collected, the flow pressure matrix reflecting the working state of the liquid injection pump is constructed, and the resonance frequency band energy characteristics are extracted to generate the pump health assessment map. Fluid scattering signals are synchronously collected and converted into a three-dimensional flow velocity vector diagram, fluid acoustic impedance parameters are calculated in combination with the flow velocity modulus and the direction change rate, and a flow field turbulence thermodynamic diagram is generated. And further dynamically matching the pump health assessment map with the turbulence thermodynamic diagram, calculating a flow field stability index, and generating a liquid injection pump adjusting instruction and a fault early warning report according to a preset risk threshold value and a deviation degree. And through multi-source data fusion and dynamic correlation analysis, real-time monitoring and active regulation and control on the stability of the in-situ leaching uranium mining flow field and the health state of the liquid injection pump are realized. According to the technical scheme, the efficiency and precision of quantitative analysis of the flow field can be improved.

The invention discloses a multi-unit sound production device, which comprises a plurality of sound production units and a passive sound production module, wherein at least one sound production unit is connected with a resonant cavity through a sound guide tube, and the resonant cavity is further connected to the passive sound production module to form an acoustic excitation path in which the low-frequency-band sound production unit drives the extremely-high-frequency-band passive sound production module; the plurality of sound production units and the passive sound production module are respectively connected to an auditory meatus outlet through respective sound guide tubes; the resonant cavity is arranged to be of a micro-cavity structure so as to be matched with the acoustic impedance of the passive sound production module in a specific extremely high frequency band response range. According to the invention, a cross-band acoustic feedback coupling mechanism is established by introducing a sound guide channel and a resonant cavity structure between the sound production unit and the passive unit, and dynamic regulation and control and frequency response optimization of frequency band sound energy are realized on the premise of not influencing normal output of an original active loudspeaker.

The invention belongs to the technical field of respiratory therapy equipment control, and discloses a multi-band airway vibration sputum excretion adaptive optimization system, which obtains acoustic impedance distribution data of each micro-section of the inner wall of the airway of a patient through an acoustic impedance imaging technology, accurately recognizes an abnormal region of a tissue interface, and improves the accuracy of sputum excretion. And calculating a reflection enhancement coefficient and a transmission attenuation coefficient of the vibration wave in the areas. And based on the multi-path interference model and the sputum excretion demand priority matrix, a multi-band vibration wave composite field with phase modulation characteristics is generated, and effective compensation of the energy transfer efficiency of the abnormal region of the tissue interface is realized. A closed-loop feedback control system is formed by monitoring spectrum characteristics of pressure pulsation signals in an airway in real time, identifying characteristic harmonic peaks and dynamically adjusting vibration wave parameters according to the characteristic harmonic peaks. The sputum excretion parameters can be optimized in real time according to individual differences of patients and sputum characteristics, the sputum excretion efficiency is remarkably improved, and discomfort of the patients is relieved.

The invention relates to the technical field of welding quality intelligent control, and discloses a friction stir welding method and system based on ultrasonic detection.The friction stir welding method based on the ultrasonic detection.The friction stir welding method based on the ultrasonic detection.The friction stir welding method based on the ultrasonic detection.The friction stir welding method comprises the following steps that the material density and the sound velocity are obtained, and acoustic impedance is calculated and matched with a wavelet basis function; pre-welding ultrasonic detection is carried out based on the function, and a defect-free reference signal is constructed; real-time ultrasonic signals and temperature and stress information are collected in the welding process; extracting features and inputting the features into a neural network, and outputting a defect probability graph; constructing a state vector and inputting the state vector into a reinforcement learning module; outputting and executing a welding parameter adjusting action; and predicting the performance by using a physical information neural network, and triggering parameter resetting when the performance is lower than a threshold value. The method for constructing the defect probability graph based on the ultrasonic data is adopted, the ultrasonic detection signals are mapped into the space probability distribution graph, visual perception of the defects in the welding seam is achieved, and the technical effect that potential defects in the welding area can be accurately recognized without damaging a sample piece is achieved.

The invention discloses a preparation method of a high-developability metal guide wire for an ultrasonic interventional operation, which comprises the following steps: selecting a material with acoustic impedance performance to prepare nanofibers through an electrostatic spinning technology, and sintering to obtain a nanofiber core; s2, mixing and ball-milling the nanofiber core obtained in the step S1 and a material with acoustic impedance performance, adding a binder, extruding, re-sintering, placing in a material tube with acoustic impedance performance, filling with material powder with acoustic impedance performance, cutting into a cylinder, and performing torsional deformation under high pressure; s3, laser bionic machining is conducted on the end point of the bar subjected to torsional deformation in the step S3, a specific lattice constant is formed, and an electron beam is provided for directional annealing of a machined product in the step S4; and a foundation is laid for inhibiting harmful artifacts generated by strong reflection of a single interface, so that the guide wire presents a clearer and more real contour in an ultrasonic image.

A transparent ultrasonic transducer device for performing multi-mode optical imaging on a target object is provided. The device includes a transparent piezoelectric transducer, one or more conductive wires, and an optical lens. The transparent piezoelectric transducer having a first acoustic impedance is configured to receive acoustic waves from the target object. The transparent piezoelectric transducer has a first surface and a second surface. The first surface and the second surface are coated with a transparent conductive coating. The optical lens contacts the first surface of the transparent piezoelectric transducer and is optically coupled to the first surface. The optical lens is made of a material having a second acoustic impedance, and the first acoustic impedance and the second acoustic impedance are substantially similar to minimize acoustic impedance mismatch, thereby improving the sensitivity of the device.

The invention belongs to the technical field of acoustic lenses, and discloses a high-frequency vortex sound field lens which comprises a stainless steel sheet substrate, the center area of the substrate is a solid area, and a periodic spiral line hollow structure is formed on the periphery of the solid area through laser processing; the area where the spiral line hollow structure is located allows sound waves to pass without shielding, and the solid area blocks sound wave propagation. The ultra-short pulse laser micromachining technology is adopted, the spiral line hollowed-out structure with the screw pitch, the line width and the spiral angle strictly matched with the high-frequency sound wave wavelength can be accurately etched in the surface of the stainless steel sheet, the spiral phase gradient is accurately constructed through the acoustic impedance difference of hollowed-out area conduction-solid area blocking, and the spiral phase gradient is accurately measured. The problem of phase error amplification under high frequency is effectively suppressed, the orbital angular momentum transfer efficiency is improved to 90% or above, and stable generation of a high-frequency vortex sound field is successfully realized.

Provided in the present invention are a Lamb wave resonator and a filter, which improve the matching performance of acoustic impedance by means of adjusting and controlling local thin film thickness. Providing recesses in a piezoelectric thin film in first material areas, or forming a dielectric layer below a piezoelectric thin film in second material areas achieves local thickness adjustment for a Lamb wave resonator constituted by interdigital electrodes and having a thickness difference, such that the first material areas and the second material areas are offset with respect to each other in the thickness direction, thus suppressing a stray mode of the Lamb wave resonator; and the response filter is constructed on the basis of the resonator, so as to suppress the phenomenon of passband performance deterioration caused by the stray mode, thereby facilitating development of high-frequency large-bandwidth acoustic resonators.

The invention provides a spiral-like sensing assembly and an imaging system thereof, and belongs to the technical field of sensing and detection. The sensing assembly comprises a bottom lining layer and a vibration diaphragm layer, the bottom lining layer is of a spiral-like cavity structure, the vibration diaphragm layer comprises a supporting layer, a plurality of electrode layers and at least one piezoelectric layer, and the positions of the supporting layer, the electrode layers and the piezoelectric layer correspond to each other and are geometrically matched. The plurality of sensing units with different sizes are arranged according to a spiral-like path, and the wave crests and the wave troughs of sensitivity curves are mutually compensated and coupled; the imaging system is composed of a spiral array formed by the sensing assembly, a sound wave emission unit, a central processing module and a display device, and the array further comprises a sound impedance matching layer to improve the sound energy transmission efficiency. The response bandwidth of the sensing assembly is effectively widened, the detection sensitivity and precision of the imaging system are remarkably improved, and the method can be applied to target detection, position calibration and route planning, underwater acoustic communication transmission, fishery breeding monitoring, geological structure exploration and the like; and a certain reference is provided for exploration of light weight and informatization of future equipment.

An ultrasound probe according to an embodiment includes a transducer part, a contact part, and an acoustic transmission layer. The transducer part has plural transducers that transmit and receive ultrasound. The contact part comes into contact with a subject. The acoustic transmission layer is arranged between the transducer part and the contact part and is formed of a material low in ultrasonic attenuation rate. Furthermore, the acoustic transmission layer has a thickness in a range of 2.3 mm to 4.7 mm and is formed using a material having an acoustic impedance of 1.4 MRayl or more and 1.6 MRayl or less.

This application discloses a planar scanning-based immersion battery thermal runaway identification device and method, relating to the field of battery energy storage safety monitoring technology. The device consists of a fully enclosed immersion tank, immersion liquid, ultrasonic phased array sensors located at the corners of the inner wall of the tank, and a signal processing module. The sensors are installed below the liquid surface and above the individual battery cells, emitting fan-shaped ultrasonic beams to form a horizontal logical scanning plane covering the entire diagonal length of the bottom surface of the module. This identification method employs active scanning and physical feature extraction logic: first, an environmental acoustic impedance reference spectrum is established using phased array beams; then, echo changes within the scanning plane are monitored in real time. This invention effectively eliminates the interference of battery bulging and mechanical vibration on traditional monitoring methods, achieving refined characterization and centimeter-level precise positioning of the gas-generating physical characteristics during the thermal runaway evolution process, significantly improving the intelligent safety level of immersion energy storage systems.

The embodiment of the invention provides a surface acoustic wave device and an electronic module, and the device comprises a piezoelectric substrate and an IDT electrode, and the IDT electrode is located at one side of the piezoelectric substrate. The IDT electrode includes: bus bars including a first bus bar and a second bus bar facing each other in a first direction; the first bus bar is provided with a plurality of first electrode fingers and a plurality of first dummy electrode fingers, and the first electrode fingers and the first dummy electrode fingers are alternately arranged and extend from the first bus bar to the second bus bar; the second bus bar is provided with a plurality of second electrode fingers and a plurality of second dummy electrode fingers, and the second electrode fingers and the second dummy electrode fingers are alternately arranged and extend from the second bus bar to the direction of the first bus bar; a plurality of first acoustic impedance pattern grooves are formed in the first bus bar at intervals in the first direction; and / or the second bus bar is provided with a plurality of second acoustic impedance pattern grooves at intervals along the first direction.

The invention belongs to the technical field of ultrasonic transducers, and particularly relates to a multi-layer high-performance ultrasonic transducer matching layer structure and a preparation method thereof. The matching layer structure at least comprises five slurry layers with different acoustic impedances, and every two adjacent slurry layers are firmly combined through interface crosslinking; the formula of each slurry layer consists of the following components in parts by weight: 100 parts of a polymer matrix; the polymer matrix is one of polyurethane, epoxy resin and polyimide; 40 to 600 parts of an acoustic filler; the acoustic filler is one or a combination of more of metal powder, hollow glass microspheres and polymer hollow microspheres; 5 to 30 parts of a cross-linking agent; the cross-linking agent is a silane cross-linking agent. Continuous gradual change of acoustic impedance is achieved, the size is smaller, and the performance is more uniform and controllable.

The invention relates to the technical field of aquaculture water treatment, and discloses a fishpond multi-stage purification and filtration system and a filtration dam device.The fishpond multi-stage purification and filtration system comprises a multi-stage flow guide filtration dam, a piezoelectric-biological coupling reactor and a self-adaptive resonance control system.The piezoelectric-biological coupling reactor is filled with piezoelectric composite biological filler, and a micro electric field is generated through ultrasonic excitation; the piezoelectric-biological coupling reactor and the biological membrane cooperate to degrade pollutants, the adaptive resonance control system monitors an acoustic impedance characterization value in the piezoelectric-biological coupling reactor in real time, ultrasonic output parameters are adaptively adjusted through a differential algorithm according to deviation, and dynamic regulation and control and in-situ updating of the thickness of the biological membrane are achieved; and an anoxic autotrophic denitrification and reoxygenation reflux device is also arranged at the rear end of the system. Through microcosmic coupling of piezoelectric catalysis and biodegradation and intelligent closed-loop feedback control, synchronous and efficient removal of refractory organic matters and ammonia nitrogen is realized, and high activity and long-acting stable operation of the purification system are ensured.