Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

2409 results about "Acoustic wave" patented technology

Acoustic waves (also known as sound waves) are a type of longitudinal waves that propagate by means of adiabatic compression and decompression. Longitudinal waves are waves that have the same direction of vibration as their direction of travel. Important quantities for describing acoustic waves are sound pressure, particle velocity, particle displacement and sound intensity. Acoustic waves travel with the speed of sound which depends on the medium they're passing through.

Underwater comprehensive detection system

The invention relates to the technical field of underwater detection, and discloses an underwater comprehensive detection system. The system collects multi-dimensional acoustic data including sound wave reflection intensity, propagation time delay and frequency dispersion characteristics of a target water area through an underwater sonar array; dividing the detection area into a plurality of layered units according to a water attenuation coefficient and a substrate reflection characteristic of the acoustic data, and extracting an environment intrinsic parameter of each layered unit; constructing an acoustic propagation path model based on the environmental intrinsic parameters, and generating adaptive filtering parameters in combination with a preset noise suppression strategy; calling sonar array hardware configuration data, matching filtering parameters with an array beam forming mode, and calculating a detection sensitivity threshold value of each layered unit; and integrating the sensitivity threshold and the acoustic data, generating a three-dimensional acoustic characteristic spectrum of the target water area, and marking the space coordinates and confidence level of the abnormal area. The system can improve the comprehensiveness and accuracy of underwater detection, and meets the requirement of high-precision detection.
Owner:NINGBO SHANGHANG SURVEYING & MAPPING

Energy harvesting acoustic metasurface using piezoelectric transducers

The technology described herein is directed towards resonators that incorporate or are closely coupled to transducers from which energy is harvested. The resonators can be unit cells of a metasurface configured for narrowband sound absorption by phase cancellation of the acoustic wave Electroacoustic transducers such as piezoelectric transducers can be positioned, e.g., at the neck ports of the resonators, to generate electricity as the air pressure of incoming acoustic waves enters the unit cells. Energy can be harvested from the electricity, and stored for usage and / or used directly to power a device. Such a device powered by the harvested energy can change the resonant frequency of the device, e.g., by changing temperatures in the resonators' air cavities, changing respective dimensions of the respective air cavities, or changing the resonant frequency of the unit cells resonators by changing respective airflow in the respective air cavities.
Owner:DELL PROD LP

Radial frequency doubling sound filtering metamaterial and topological optimization design method thereof

The invention relates to a radial frequency-doubled sound filtering metamaterial and a topological optimization design method thereof.The radial frequency-doubled sound filtering metamaterial comprises scatterers which are arranged on a base body and distributed in a concentric circle mode, and the topological optimization design method comprises the following steps that a two-dimensional axial symmetry model is established, the two-dimensional axisymmetric model corresponds to the cross section of the radial frequency-doubled sound filtering metamaterial in the radius direction and comprises periodically arranged unit structures, and each unit structure comprises a main board and a square design domain; a Floquet periodic boundary condition is applied to parallel boundaries of a unit structure in the radius direction, other boundaries are set as free boundaries, a genetic algorithm is adopted to carry out iterative optimization on the material distribution topology of a square design domain, the optimal material distribution topology of the square design domain is obtained, and then the final optimized shape of the radial double-frequency sound filtering metamaterial is obtained. Compared with the prior art, the invention has the advantages of capability of realizing omni-directional sound wave frequency doubling filtering, high design reliability and the like.
Owner:EAST CHINA UNIV OF SCI & TECH

Ultrasonic detection method and system for inverting residual stress by using sound wave phase velocity

The invention provides an ultrasonic detection method and system for inverting residual stress by using sound wave phase velocity, and belongs to the field of air coupling ultrasonic guided wave detection. The method is based on an air coupling ultrasonic guided wave sound field propagation finite element model, and guides optimization design of air coupling ultrasonic transducer parameters. The air coupling ultrasonic guided wave detection technology is adopted for conducting non-contact excitation and receiving of guided wave signals on the composite material component with the preset stress through the stretcher. And calculating the phase velocity of the air-coupled ultrasonic guided wave in the composite material component based on a geometric positioning and time difference cooperative gradual difference method. And calibrating the phase velocity in the target composite material and preset stress to obtain a corresponding relational expression, performing phase velocity detection on a composite material component with unknown stress based on a calibration result of the target composite material, and performing inversion to obtain composite material construction residual stress. By adopting the method and the system, the residual stress detection of the composite material component is realized.
Owner:BEIHANG UNIV +1

Bulk acoustic wave device with capacitor

Aspects of this disclosure relate to a bulk acoustic wave resonator and an integrated capacitor. In certain embodiments, the integrated capacitor can be a metal-insulator-metal capacitor in parallel with the bulk acoustic wave resonator. The metal-insulator-metal capacitor can include a portion of a first electrode and a portion of a second electrode of the bulk acoustic wave resonator. At least part of the metal-insulator-metal capacitor is positioned laterally relative to an acoustic reflector of the bulk acoustic wave resonator. Other embodiments of capacitors integrated with a bulk acoustic wave resonator are disclosed. Related filters, multiplexers, radio frequency modules, radio frequency systems, wireless communication devices, and methods are disclosed.
Owner:SKYWORKS GLOBAL PTE LTD

Acoustic metasurface with aperture switching modularity

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies selected via interchangeable portions. A sound absorbing unit cell is designed and constructed in two parts based on a desired resonance frequency, such as a neck portion and air chamber portion. The portions are dimensioned such that when coupled together, Helmholtz resonators are formed that resonate at a desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. A portion with different dimensions can be interchanged to adjust the resonant frequencies to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Boiler leakage prevention online monitoring method and monitoring system

The invention discloses a boiler leakage prevention on-line monitoring method and system, and relates to the technical field of boiler leakage monitoring, and the method comprises the following steps: S100, collecting an infrared image and a visible light image of a monitoring area in real time through an image collection module, and transmitting the data to a preprocessing module; s200, a preprocessing module carries out denoising and edge strengthening processing, conventional edge features are reserved, and tiny temperature difference features are focused; s300, the control module rejects interference factors based on the similarity of the infrared image and the visible light image to obtain a suspected leakage image; s400, carrying out data acquisition on the suspected leakage region by using an acoustic imaging module, analyzing and recording the region data by a deep learning module based on historical detection data, and constructing a time sequence model; and S500, the control module analyzes and judges the overlapping state of the pipeline at the leakage point according to the visible light image and the information collected by the sound wave imaging module, and locates a leakage source.
Owner:河南省锅炉压力容器检验技术科学研究院

Multi-function bimorph microelectromechanical systems integration (MEMS) for analog tunability in metasurfaces

The technology described herein is directed towards a metasurface arranged with unit cells for narrowband sound absorption, in which the unit cells are based on Helmholtz resonators that can have their resonant frequencies adjusted via MEMS actuators. A sound absorbing unit-cell is designed and constructed based on a general resonance frequency, and includes a neck portion and air chamber dimensioned to resonate close to the desired resonance frequency and thereby inverse phase cancel corresponding narrowband frequencies of incoming sound waves. A bimorph MEMS actuator and / or moveable part in the resonators, controlled by a controller, facilitates changing of the airflow the unit cells to adjust the resonant frequencies thereof, to cancel acoustic waves of different frequencies corresponding to noise, which can change over time. The unit cells can be distributed as part of a metasurface, which can be positioned proximate to a noise source to phase cancel the noise.
Owner:DELL PROD LP

Heat pump type whole vehicle heat management system and method for pure electric vehicle

The invention discloses a pure electric vehicle heat pump type whole vehicle thermal management system and method, and relates to the technical field of new energy vehicle thermal management, and the method comprises the following steps: constructing a combined twin system of thermal fluid, structural vibration and acoustic fluctuation, collecting pressure waves and vibration phases by using an array sensor, forming a steady state baseline spectrum and a transient state baseline spectrum, and calculating the temperature of the steady state baseline spectrum and the transient state baseline spectrum; and a unified reference is established. According to the method, a combined twinborn system of thermal fluid, structural vibration and acoustic fluctuation is constructed, the dynamic characteristics of pulsating waves are accurately monitored, and instability early warning is carried out by using a phase locking tracking method. Through pipeline topology reconstruction and segmented damping link design, a self-adaptive pulsation buffer zone is introduced, and pulsation energy is effectively absorbed. And in combination with a multi-target control law and a time reflection mirror cooperative regulation strategy, refrigerant flow is accurately controlled, pulsation energy is actively counteracted, and stable operation of the system is guaranteed. Through the innovative design, the stability of a heat management loop is improved, the fault risk caused by pulsation is reduced, and the cooling efficiency and safety are improved.
Owner:HEFEI UNIV OF TECH

Acoustic coalescence elimination method for hydrogen bubbles in molten aluminum

The invention provides an acoustic coalescence elimination method for hydrogen bubbles in molten aluminum, and belongs to the technical field of molten aluminum bubble elimination. According to the method, sound field collaborative focusing is achieved by arranging a phase control array transducer set in a molten aluminum smelting furnace, primary gathered sound waves and efficient coalescence sound waves are applied in stages according to bubble size evolution in a double-frequency scanning mode, and the hydrogen bubbles in the molten aluminum are eliminated. A target frequency is dynamically adjusted in combination with a bubble resonance frequency optimization model to match the inherent frequency of a bubble, a sound-bubble coupling dynamic tracking system is used for monitoring bubble evolution triggering stage switching in real time, and a sound field focus point dynamically scans and covers a three-dimensional space area through phase delay control. A delay detection method is adopted to eliminate cavitation bubble interference and accurately measure the hydrogen content, sound intensity and frequency parameters are optimized according to a sound field parameter self-adaptive regulation and control model, and the technical problem that hydrogen bubbles in a molten aluminum deep area are difficult to be effectively driven by sound waves and cannot be fully coalesced and eliminated is solved.
Owner:QINGDAO UNIVERSAL ALUMINUM IND CO LTD

Acoustic wave device

An acoustic wave device includes a support substrate, a piezoelectric layer on the support substrate, and at least one lithium niobate layer and first and second principal surfaces opposed to each other, and first and second IDT electrodes respectively on the first and second principal surfaces. Each of the first and second IDT electrodes includes electrode fingers. A duty ratio of each of the first and second IDT electrodes is equal to or greater than about 0.6. Directions of polarization of the piezoelectric layer are inverted in a thickness direction of the piezoelectric layer.
Owner:MURATA MFG CO LTD

Driving and sensing integrated soft claw, gripper and method

The invention provides a driving and sensing integrated soft claw, gripper and method, and belongs to the field of deep sea soft grippers. The problems that a traditional soft gripper sensor is prone to forming stress concentration and cannot achieve multi-point sensing are solved. The driving and sensing integrated soft claw comprises a sensing layer, an acoustic wave guide main flow channel extending in the length direction is arranged on the sensing layer, and an ultrasonic transducer is arranged on the side, close to the fixed end of the sensing layer, of the acoustic wave guide main flow channel. The end face of one side of the sensing layer is a grabbing face, and a plurality of evenly-arranged protrusions are arranged in the acoustic wave guide main flow channel corresponding to the end face. And the driving layer is arranged on the side, away from the grabbing face, of the sensing layer, a plurality of deformation cavities communicating with the acoustic wave guide main flow channel are formed in the driving layer, the driving layer is in a stretching state in a normal state, and when the deformation cavities are filled with liquid and pressurization continues, the deformation cavities are used for deforming to drive the sensing layer to bend. The manipulator is mainly used for grabbing actions.
Owner:HARBIN ENG UNIV

Multi-mode signal fusion switch cabinet partial discharge detection and positioning method and device

The invention discloses a multi-mode signal fusion switch cabinet partial discharge detection and positioning method and device, and belongs to the technical field of power equipment monitoring, and the method comprises the steps: arranging an ultrahigh frequency sensor, an ultrasonic sensor and a traveling wave signal sensor on a switch cabinet, and synchronously collecting electromagnetic wave, sound wave and traveling wave signals; filtering the electromagnetic wave signal, the sound wave signal and the traveling wave signal, and enhancing the filtered signal to obtain a filtered enhanced signal; carrying out the positioning and classification of the partial discharge signals through the multi-modal feature fusion of the filtered enhanced signals; and triggering graded alarm according to a positioning result, and periodically starting a self-checking program to verify the reliability of the sensor and the algorithm. Physical characteristics of different discharge types are covered, the detection comprehensiveness is improved, the noise interference problem is solved, and the data fusion efficiency and the positioning precision are improved; the system health state is monitored in real time, and long-term operation stability is ensured.
Owner:STATE GRID QINGHAI ELECTRIC POWER COMPANY +1

Blocking Plate Structure for Improved Acoustic Transmission Efficiency

An acoustic matching structure is used to increase the power radiated from a transducing element with a higher impedance into a surrounding acoustic medium with a lower acoustic impedance. The acoustic matching structure consists of a thin, substantially planar cavity bounded by a two end walls and a side wall. The end walls of the cavity are formed by a blocking plate wall and a transducing element wall separated by a short distance (less than one quarter of the wavelength of acoustic waves in the surrounding medium at the operating frequency). The end walls and side wall bound a cavity with diameter approximately equal to half of the wavelength of acoustic waves in the surrounding medium. In operation, a transducing element generates acoustic oscillations in the fluid in the cavity. The transducing element may be an actuator which generates motion of an end wall in a direction perpendicular to the plane of the cavity to excite acoustic oscillations in the fluid in the cavity, and the cavity geometry and resonant amplification increase the amplitude of the resulting pressure oscillation. The cavity side wall or end walls contain at least one aperture positioned away from the center of the cavity to allow pressure waves to propagate into the surrounding acoustic medium.
Owner:SIM IP HXR LLC

Cable fault diagnosis method and system based on multi-mode composite fusion

The invention provides a cable fault diagnosis method and system based on multi-modal composite fusion. The method comprises the following steps: synchronously acquiring and performing time-space alignment on distributed acoustic, temperature and high-frequency pulse signals along a cable path; the acoustic signal is decoupled into an internal event channel and an external interference channel by time domain polarization analysis. And calculating the acoustic nonlinear index of the candidate event in the internal channel, dynamically correcting the judgment threshold value of the candidate event by using the real-time temperature signal, and performing cross-modal correlation verification with the high-frequency pulse signal so as to confirm that the candidate event is an electrical discharge event. And if the judgment result is true, an acoustic wave field data array of the event is extracted, and a passive synthetic aperture focusing algorithm is applied to reconstruct a two-dimensional morphological acoustic image of the fault source. And finally, integrating all information to generate a comprehensive diagnosis report. The technical problem that a traditional distributed sensing method can only provide one-dimensional fault positioning and cannot perform high-confidence qualitative and multi-dimensional morphological representation on the fault is solved.
Owner:CHINA RAILWAY WUHAN SURVEY & DESIGN CO LTD

FBAR-based MIM on-chip capacitor and high-integration chip structure thereof in hybrid FBAR circuit

The invention relates to an FBAR-based MIM on-chip capacitor, a high-integration chip structure of the FBAR-based MIM on-chip capacitor in a hybrid FBAR circuit, and electronic equipment. The chip structure comprises a film bulk acoustic resonator and a capacitor which are arranged on the same substrate; the film bulk acoustic resonator comprises an acoustic wave reflection structure, and a lower electrode, a piezoelectric layer and an upper electrode which are laminated on the acoustic wave reflection structure. The capacitor comprises an upper electrode, a lower electrode and a central dielectric layer, wherein the upper electrode and the lower electrode are stacked on at least three metal layers formed on a substrate; the dielectric constant of the central dielectric layer is greater than 6; the thickness of each metal layer in the upper electrode and the lower electrode of the capacitor is not less than the skin depth, and the outermost upper electrode sub-layer and the outermost lower electrode sub-layer are the sub-layers with the largest thickness in the metal layers; the middle layer upper electrode sub-layer and the resonator upper electrode are made of the same material, the middle layer lower electrode sub-layer and the resonator lower electrode are made of the same material, the innermost layer upper electrode sub-layer and the innermost layer lower electrode sub-layer are not diffused with the material of the central dielectric layer, and the area of the capacitor is not larger than five times of the area of the film body acoustic resonator.
Owner:SUZHOU HUNTERSUN ELECTRONICS CO LTD +1

Three-dimensional temperature field online reconstruction system based on transmitting and receiving integrated sound wave sensing

The invention discloses a three-dimensional temperature field online reconstruction system based on receiving and transmitting integrated sound wave sensing, and relates to the field of boiler monitoring. Comprising an information acquisition module, an emission control module, a reconstruction sensing module, a path optimization module, a sound wave receiving module, an amplitude limiting filtering module, a decoding separation module, a feature extraction module, a physical simulation module, a multi-source fusion module, a three-dimensional reconstruction module, a state monitoring module and an online calibration module. According to the method, the transmitted signal can still keep high identifiability in a high-noise and strong-interference background, the credibility of subsequent inversion and data assimilation is improved, a sensing network can be self-optimized, the observation precision and the space coverage capability are improved, a wide dynamic range and high linearity are realized, a simulation result is closer to a real working condition, and the method is suitable for large-scale popularization and application. And the reliability of temperature field inversion is obviously improved.
Owner:NANJING GUOQING POWER EQUIP CO LTD

Acoustic wave device and acoustic wave filter device

An acoustic wave device includes a piezoelectric layer including first and second major surfaces, an IDT electrode on one of the first and second major surfaces, and including electrode fingers arranged in an arrangement direction, and a support facing the second major surface, and including an acoustic reflection portion facing the second major surface. The electrode fingers include a first electrode finger at an outermost position in the arrangement direction and a second electrode finger adjacent thereto. A product of a width, height, and density of one of the first and second electrode fingers is greater than a product of a width, height, and density of a central electrode finger. When the thickness of the piezoelectric layer is denoted by d and a center-to-center distance between adjacent electrode fingers is denoted by p, d / p is less than or equal to about 0.5.
Owner:MURATA MFG CO LTD

Cable fault diagnosis and positioning method and system based on DTS and DAS fusion

The invention discloses a DTS and DAS fusion-based cable fault diagnosis and positioning method and system, and the method comprises the steps: synchronously collecting a distributed temperature sensing signal and a distributed sound wave sensing signal through a single sensing optical fiber which is laid together with a cable, and carrying out the time-space synchronization processing, obtaining temperature field data and phase disturbance field data which are aligned under the same space-time coordinate; calculating a cross-modal coherence spectrum of the temperature field data and the phase disturbance field data, quantifying physical coupling strength of vibration and temperature, and screening out potential fault candidate regions with coupling correlation; for the potential fault candidate region, adopting a dynamic attention mechanism of adaptive adjustment of a temperature change rate to perform nonlinear semantic fusion on the temperature feature and the vibration time-frequency feature to generate a fusion feature manifold; and calculating an entropy anomaly index reflecting a feature concentration ratio based on the generated fusion feature manifold, performing weighted calculation in combination with the coupling strength of the cross-modal coherence spectrum, and outputting an accurate spatial position and a fault type of a cable fault.
Owner:STATE GRID FUJIAN ELECTRIC POWER CO LTD +1

Karst cave group detection method and device in shield construction

The invention provides a karst cave group detection method and device in shield construction, and the method achieves the comprehensive detection of karst caves through a transient electromagnetic and sound wave array composite wave field detection mode, and improves the detection accuracy and detection efficiency of the karst cave group. And feature extraction is performed on the composite wave field detection data through a cross-physical coupling model, a karst cave probability model is established, and quantitative evaluation of a karst cave detection result is realized. When the karst cave possibly exists in the construction direction of the shield tunneling machine, the distribution prediction direction of the karst cave is further determined, and the shield tunneling machine is prevented from entering the karst cave area blindly in the tunneling process. Through the multi-source sensing array carried on the shield tunneling machine, equipment parameters during operation of the shield tunneling machine are collected in real time, potential construction anomalies can be found easily, and the accuracy and timeliness of karst cave detection are improved. Combined analysis is carried out on the composite wave field detection data and the operation parameters of the shield tunneling machine through the risk assessment model, a karst cave risk prediction value is determined, and the accuracy of karst cave risk assessment is improved.
Owner:CHINA RAILWAY INVESTMENT GRP CO LTD +3

Cast-in-place pile quality online monitoring method and system based on ultrasonic array

The invention provides a cast-in-place pile quality online monitoring method and system based on an ultrasonic array, and the method comprises the steps: transmitting and receiving ultrasonic waves through the ultrasonic array arranged in a cast-in-place pile, and obtaining a multi-channel sound wave signal; performing generalized S transformation processing on the multichannel sound wave signals to obtain a time-frequency matrix, and calculating a cross correlation coefficient between each channel signal and the defect-free reference signal; an amplitude matrix and an instantaneous phase gradient matrix are calculated based on the time-frequency matrix, neighborhood amplitude energy and a phase consistency factor are fused in a time-frequency domain, and a defect energy indication diagram of the pile body section is generated; calculating the energy entropy of the defect energy indication diagram in a full frequency band; and extracting an actually measured energy arrival time sequence, comparing the actually measured energy arrival time sequence with a theoretical arrival time sequence to construct a space distortion vector, and setting a threshold value by combining energy entropy to judge defects.
Owner:中建五局第四建设有限公司

Acoustic wave device having multiple piezoelectric layers between electrodes

Aspects of this disclosure relate to an acoustic wave device with a plurality of piezoelectric layers positioned laterally relative to each other between two electrodes. One of the piezoelectric layers has a different property than another of the piezoelectric layers. Examples of the different property include c-axis orientation, doping concentration, dopant material, and piezoelectric material. At least part of each of the piezoelectric layers can be in a main acoustically active region of the acoustic wave device.
Owner:SKYWORKS SOLUTIONS INC

Two-stage cascade type distributed optical fiber sound wave sensing vehicle track reconstruction method and two-stage cascade type distributed optical fiber sound wave sensing vehicle track reconstruction system

The invention discloses a two-stage cascaded distributed optical fiber sound wave sensing vehicle trajectory reconstruction method and system, belongs to the technical field of intelligent traffic perception, and aims to solve the problem that geometric accuracy and topological integrity are difficult to consider under the conditions of low signal-to-noise ratio and complex road conditions in the conventional DAS vehicle trajectory reconstruction technology. The method comprises the following steps: in the first stage, carrying out nonlinear enhancement on original vibration data and converting the original vibration data into a two-dimensional space-time grayscale image, inputting the two-dimensional space-time grayscale image into a deep learning semantic segmentation network to generate a high-fidelity track mask, extracting a skeleton through morphological processing, and constructing an initial candidate topological graph; and in the second stage, multi-hop neighborhood kinematics constraint pruning is performed on the initial topological graph, false connection edges are eliminated, global optimization matching is performed by using a coupling cost function to repair fractures, then isolated points are recalled through local geometric scores, and finally a vehicle trajectory graph with complete topology is output. According to the method, geometric accuracy and topological integrity can be effectively considered in complex scenes such as speed change, lane change and multi-vehicle intersection, and the robustness of all-weather traffic flow monitoring is improved.
Owner:HARBIN INST OF TECH

Aero-engine blade surface coating defect and thickness detection method

The invention relates to the technical field of aero-engine nondestructive testing, and discloses a method for detecting defects and thickness of a surface coating of an aero-engine blade. The invention designs a novel acoustic impedance sensor special for a blade coating, the novel acoustic impedance sensor comprises a plurality of independently controlled transduction units, each transduction unit has multi-band detection capability, main resonant frequencies of different transduction units are configured in a differentiated manner, and during detection, the novel acoustic impedance sensor is coupled to the surface of a blade; the material state is reversely deduced by measuring the energy absorption spectrum of broadband sound waves in the coating, and the blade surface coating defect and thickness detection is achieved.
Owner:EDDYSUN (XIAMEN) ELECTRONICS CO LTD

Spiral resonance photoacoustic cell and operation method

The invention discloses a spiral resonance photoacoustic cell and an operation method, the spiral resonance photoacoustic cell comprises a gas chamber straight tube, a spiral tube, an optical fiber collimator and an optical fiber F-P sonic sensor, the two ends of the gas chamber straight tube are open, the two ends of the spiral tube are communicated with the gas chamber straight tube, an acoustic resonance point is formed at the center of the spiral tube, and the optical fiber F-P sonic sensor is arranged in the central area of the spiral tube; and the optical fiber collimator is arranged at one end of the air chamber straight pipe. The spiral pipe is wound outside the air chamber straight pipe, the spiral pipe is communicated with the air chamber straight pipe, the structural design of the spiral pipe enables the spiral pipe to form acoustic resonance at a specific frequency, and the optical fiber F-P sonic sensor obtains a photoacoustic signal; compared with a conventional resonance photoacoustic cell, the physical volume of the resonance photoacoustic cell is greatly compressed, and the system integration level is effectively improved. More importantly, under the condition that a compact appearance similar to that of a non-resonant photoacoustic cell is kept, the device amplifies the photoacoustic signal intensity by several times through an acoustic resonance effect, and the detection sensitivity and the signal-to-noise ratio of the system are remarkably improved.
Owner:江淮前沿技术协同创新中心 +1

Multi-component gas concentration detection system

The present invention discloses a multi-component gas concentration detection system, which relates to the field of gas concentration detection, and comprises: a light source, which is used for emitting detection light covering the absorption wave band of a target gas; the light splitting assembly is used for dispersing the detection light and at least splitting the detection light into a first light beam and a second light beam; the air chamber is provided with an optical signal detection module and an acoustic signal detection module; the first light modulator is used for carrying out wavelength selection and modulation on the second light beam; wherein the first light beam is received by the light signal detection module to form an absorption spectrum detection light path; the second light beam is absorbed by the gas to be detected and then excites a sound wave signal through a photoacoustic effect, and the sound wave signal is received by the sound signal detection module to form a photoacoustic spectrum detection light path. By adopting the scheme, synchronous detection of multi-component gas, compactness of a detection structure and high-sensitivity detection of low-concentration gas can be considered.
Owner:SHANGHAI CHEYITIAN TECH CO LTD

Strip mine slope slippage trend early warning system based on active micro-vibration excitation

The invention relates to the technical field of strip mine side slope slippage trend early warning, and particularly discloses a strip mine side slope slippage trend early warning system based on active micro-vibration excitation, which comprises the following components: an excitation unit which is composed of a frequency-adjustable micro-vibration exciter which periodically applies low-amplitude controllable mechanical disturbance signals to a side slope rock mass, the rock-soil medium structure response is excited, and the early warning sensitivity is improved; the sensing unit comprises a three-axis acceleration sensor, a displacement meter, a GNSS (Global Navigation Satellite System) sensor and a ground acoustic wave sensor, and is used for recording response change in a vibration disturbance signal propagation process and obtaining data; the analysis unit comprises an edge intelligent terminal, a slippage trend identification model built in the edge intelligent terminal and a lightweight neural network, and the slippage trend identification model performs sensing processing on the data and outputs a slippage trend label; and the communication control unit is used for ensuring that the data streams of the units are stable and cooperatively run with the modules.
Owner:INNER MONGOLIA UNIV OF TECH +1

Acoustic wave device and acoustic wave device manufacturing method

An acoustic wave device includes a support substrate including a first crystal axis, first and second intermediate layers, a piezoelectric layer including a second crystal axis, and a functional electrode on the piezoelectric layer. The support substrate, the first and second intermediate layers, and the piezoelectric layer are arranged in this order. The first crystal axis is inclined at a first inclination angle with respect to a direction normal to the support substrate. The second crystal axis is inclined at a second inclination angle with respect to a direction normal to the piezoelectric layer. The first and second inclination angles are equal to each other. Rotational symmetry of the piezoelectric layer with respect to the second crystal axis is equal to rotational symmetry of the support substrate with respect to the first crystal axis.
Owner:MURATA MFG CO LTD

Underground oil pipe leakage detection system

The invention relates to the technical field of oil pipe leakage detection, in particular to an underground oil pipe leakage detection system, which comprises an underground permanent monitoring unit, which comprises at least one optical fiber sensor, and the optical fiber sensor clings to the outer wall of a production oil pipe or is integrated in an oil pipe coupling and extends along the depth of a whole shaft; the ground signal processing and analyzing unit is in communication connection with the underground permanent monitoring unit; wherein the optical fiber sensor is used as a distributed temperature sensor and a distributed sound wave vibration sensor at the same time, real-time on-line monitoring of oil pipe leakage is achieved, early warning can be given out at the initial stage of leakage, the accuracy of leakage recognition is improved through collaborative analysis of bimodal sensing data, the false alarm situation is effectively reduced, and the reliability of oil pipe leakage detection is improved. A distributed measurement mode provides meter-scale spatial resolution, the depth position of a leakage point is accurately positioned, normal production operation does not need to be interrupted during system operation, and the operation cost of an oil field is reduced.
Owner:CHINA UNIV OF PETROLEUM (EAST CHINA)

Underground coal mine goaf gap space sensing method based on multiple detection technology

The invention discloses an underground coal mine goaf gap space sensing method based on a multiple detection technology, and the method comprises the steps: obtaining a three-dimensional dielectric constant body through a ground penetrating radar, and determining the space position of a goaf gap; resistivity tomography is carried out through the optimally arranged electrode network, and a three-dimensional resistivity body is inverted; constructing a three-dimensional wave velocity body by adopting sound wave detection, and identifying a velocity low-value region; a dielectric constant body, a resistivity body and a wave velocity body obtained by the three technologies are uniformly registered to a cubic grid with a preset resolution and normalized, a caving zone void probability body is constructed by adopting adaptive weighted fusion based on information entropy and a Bayesian maximum posteriori estimation framework, and finally a three-dimensional void model is generated and the total volume is calculated. Through multi-source data fusion of ground penetrating radar, resistivity tomography and sound wave detection, the limitation of a single technology in goaf space detection is solved, the precision of gap detection is improved, and the method is suitable for goaf space perception and treatment.
Owner:中煤能源研究院有限责任公司 +1