565 results about "Frequency sound" patented technology

The invention belongs to the technical field of vehicle state detection and early warning, and particularly relates to a vehicle state monitoring and early warning method and system.The monitoring and early warning method comprises the steps that a sensor obtains real-time data, an anomaly detection algorithm is applied, and an abnormal event is marked; calculating an information priority according to the abnormal severity and the driving scene, and distributing the information priority to a high-priority queue; multi-mode early warning is generated, and high-frequency sound and vibration are used during high-speed driving; extracting a voice prompt, and generating voice waveform data through a voice synthesis module; voice input of a driver is recognized, intention is analyzed, and abnormal information feedback is provided; according to the scene and the abnormal state, interactive output is optimized, and detailed information is displayed during low-speed congestion; dynamically adjusting the interface of the instrument panel, and amplifying the key area in case of abnormal severity; and integrating the image data and the voice data, generating a multi-mode signal, and transmitting the multi-mode signal after rendering processing. The vehicle abnormal information can be timely and accurately transmitted to a driver, and the driving safety is effectively improved.

The invention provides a broadband sound absorption structure suitable for undercarriage cabin door noise reduction and a design method, and belongs to the field of aircraft noise reduction. The sound absorption structure comprises a plurality of perforated plate type Helmholtz cavity unit cells and a plurality of embedded pipe type Helmholtz cavity unit cells. In the perforated plate type unit cells, one or more first through holes are formed in the perforated plate. And in the embedded pipe type unit cells, the embedded pipes penetrate through the perforated holes in the perforated plates and extend into the cavities. Cavities of the two single cells face the same direction, and the perforated plate forms a curved surface conformal with an undercarriage cabin door. The effective length of the neck of the perforated plate is increased by using the embedded pipe, the low-frequency sound absorption performance is improved, the sound absorption performance and the sound absorption bandwidth of the middle-frequency band are improved by using the perforated plate type Helmholtz cavity, meanwhile, the curved surface conformal design is highly matched with the special-shaped cabin door structure, and the sound absorption performance is improved. The low-frequency and medium-frequency sound absorption performance can be guaranteed, and meanwhile the light and thin requirements of an aircraft can be met; and a pure passive mechanical structure is adopted, so that the control complexity and stability risks of an active noise reduction system can be avoided.

The invention discloses a frequency mixing sound demodulator based on a curled structure and a use method thereof in the acoustics field, the demodulator is used for separating frequency mixing sound mixed by a plurality of sound waves with preset frequencies according to respective frequencies, and the demodulator comprises an air waveguide for transmitting the sound waves, and blocking structures arranged on two sides of the air waveguide for blocking the sound waves from penetrating, and a plurality of curled structures that capture corresponding preset frequency sound waves; curled structures are arranged in the barrier structure on at least one side of the air waveguide at intervals, one end of each curled structure is open, and the other side is closed; a plurality of cross beams for blocking penetration of sound waves are arranged in each curled structure, and an internal channel of each curled structure is divided into different lengths to serve as different acoustic resonant cavities so as to capture the sound waves with different frequencies; the closed end of each curled structure is a detection end of each preset frequency sound wave. The invention solves the problem that the existing method is difficult to instantly separate the frequency mixing sound signal and carry out information transmission.

The invention discloses a leakage monitoring method of a sealing connection structure for hydrogen conveying, and relates to the field of gas conveying and storage monitoring, and the method comprises the steps: S1, arranging an annular negative pressure sampling cavity to collect multi-modal data, and calculating the angle section suspiciousness; s2, applying thermal pulse and sweep frequency sound wave excitation, and collecting a response signal to generate a thermoacoustic leakage score; s3, environment compensation and multi-sensor fusion are carried out to obtain an angle section hydrogen concentration time sequence; s4, obtaining an inversion flux based on the comprehensive response and sparse-smooth inversion to realize leakage positioning; and S5, calculating a risk score and performing graded alarming according to a threshold value. Multi-point detection units are arranged in the circumferential direction of the sealing connection structure, signal fusion is adopted, full-coverage leakage monitoring and high-precision positioning of the sealing structure are achieved, emergency measures are automatically triggered in combination with risk grading, and the discovery timeliness and safety are improved.

The invention discloses a multi-channel audio calibration method, system and device and a storage medium, and relates to the technical field of audio, and the method comprises the steps: collecting and separating a main sound channel signal and a bass sound channel signal in a multi-channel audio signal; detecting time delay between a main sound channel and a bass sound channel based on a phase correlation algorithm, and performing adaptive delay compensation; the state change of the audio signal is monitored in real time, and before or when a signal switching event is detected, gradient gain envelope is applied to the bass sound channel signal, so that the signal amplitude gradually changes to a target value according to a preset nonlinear curve; a sonic boom event is analyzed and identified based on multi-dimensional characteristics, a self-adaptive amplitude limiter with a prospective processing capability is started for suppression, and harmonic distortion compensation and phase correction are carried out on a processed signal, so that the problems of signal asynchronization caused by low-frequency output delay of an audio system in the prior art, and the system reliability is improved are solved. Therefore, the low-frequency sound quality and the system stability are improved.

The invention discloses a method for realizing ocean sound field prediction based on a pre-training optimized physical information neural network, which comprises the following steps of: pre-training: constructing a hypothetical ocean environment, generating simulation data in a sound pressure envelope form by using an acoustic numerical calculation tool, and pre-training the physical information neural network to learn a physical rule of sound field propagation; fine tuning: adjusting an energy scale factor according to the proportion of the sound pressure amplitude of the actual measurement point to the sound pressure amplitude of the pre-trained environment, and performing fine tuning by using the envelope amplitude data of the actual measurement sound field for the pre-trained physical information neural network to obtain an ocean sound field prediction model through a pre-training-fine tuning dual-stage strategy; and ocean sound field prediction: according to the ocean sound field prediction model, obtaining a target position envelope from the to-be-predicted range, and then converting the target position envelope into a sound pressure result to realize ocean sound field prediction. The method can improve the high-frequency sound field modeling precision and training efficiency, and can be widely applied to the fields of ocean sound field modeling, sound source localization and environment inversion.

The invention provides a robust optimization method and device for a low-frequency sound absorption metamaterial, and relates to the technical field of punching, and the method comprises the steps: obtaining a response function of a target metamaterial through employing a linear one-dimensional rheological model; determining a target coupling region by using an imaginary part of a transfer function zero point corresponding to the response function or a size relationship between inherent loss and radiation loss as a coupling criterion, and determining a closed coupling region where a preset parameter point is located as an initial robust region; the target coupling region comprises a closed coupling region; the preset parameter point meets the one-dimensional frequency domain response of the target metamaterial; and determining the size of the initial robust region by using the Lexberg measure of the Euclidean space, and optimizing the robust region by maximizing the Lexberg measure of the initial robust region in the Euclidean space to obtain a target robust region. According to the method, the maximum robust region in the parameter space is found through maximum measurement, so that the response characteristics of the viscoelastic damping material under the actual working condition can be accurately described.

The invention provides a big data-based material detection method and system, relates to the field of material quality detection, and solves the technical problems of insufficient detection precision and poor supply chain quality control linkage in an existing material detection method. The method comprises the following steps: transmitting sweep-frequency sound waves to warehouse-in materials of a peripheral warehouse by using a sound wave transmitting device; collecting vibration velocity spectrum data and sound pressure gradient data of the warehouse-in material after the warehouse-in material receives the frequency sweep sound wave; according to the vibration velocity spectrum data and the sound pressure gradient data, calculating a defect index of the warehouse-in material; and when the defect index is greater than a preset threshold value, marking the warehousing material as a defective material, sending a traceability detection instruction to a previous node warehouse, and starting a grading detection process of the previous node warehouse. The method and the device are used for warehousing detection, quality traceability and full-chain management and control processes of the materials in the supply chain.

The invention belongs to the technical field of low-frequency sound absorption, and discloses a micro-perforated plate composite gradient spiral pipe sound absorption device and method.The micro-perforated plate composite gradient spiral pipe sound absorption device comprises a variable cross-section spiral pipe, and the diameter of the inlet end of the variable cross-section spiral pipe is larger than that of the outlet end of the variable cross-section spiral pipe; a plurality of MPP plates are mounted in the variable-cross-section spiral pipe, one MPP plate is embedded into the inlet end of the variable-cross-section spiral pipe, and the other MPP plates are sequentially embedded into the variable-cross-section spiral pipe at equal intervals, so that a multi-stage MPP plate composite sound absorption structure is formed; and the cross-section pipe diameter of the variable cross-section spiral pipe is linearly reduced from the inlet end of the variable cross-section spiral pipe to the outlet end of the variable cross-section spiral pipe. Through the gradient design of the variable cross-section spiral tube integrated micro-perforated plate, low-frequency broadband efficient sound absorption is realized in a compact space, the problem of heavy structure caused by dependence on a deep and large back cavity in the traditional technology is avoided, the limitation of narrow sound absorption frequency band is overcome, and the sound absorption device is particularly suitable for being applied to occasions with limited spaces and has wide application prospects. And low-frequency performance and broadband characteristics are considered in a limited space.

The invention discloses a low-frequency sound propagation loss forecasting method suitable for a polar region sea area, and the method comprises the steps: building a two-dimensional ice layer model of a forecast sea area according to remote sensing data based on the setting that sea ice of the polar region sea area is a uniform elastic medium; calculating hydrological conditions of the ocean sound channel of the polar sea area; establishing a forecast sea area two-dimensional seabed model according to the seabed topography sediment database; an under-ice sound field model is constructed based on a three-dimensional cylindrical coordinate system, sound pressure from unit intensity sound sources with different sizes and depths to a receiving point in a forecast sea area is calculated through a frequency domain finite element method in combination with a PML technology, and sound propagation loss of a needed position is obtained through calculation. According to the method, the application limitation of traditional ray and normal wave theories under complex boundary conditions is broken through through a finite element method, a synergistic effect mechanism of actual ice layer parameter space change, submarine topography fluctuation and sound velocity profile gradient characteristics is systematically analyzed, and sound field modeling is more accurately carried out on different ice layers and submarine topographies in the Chukong sea region all year round; the influence of sound wave propagation is simulated.

The invention discloses a low-frequency sound absorption device for a wind tunnel corner flow deflector, and the device comprises a housing which is internally provided with a low-frequency sound absorber and an impedance matching layer. The low-frequency sound absorber comprises a Helmholtz resonance cavity, a sealing ring and an elastic support, the Helmholtz resonance cavity is distributed in the sealing ring in a square lattice or rectangular lattice mode, and the sealing ring is connected with the shell through the elastic support; the impedance matching layer comprises a porous material layer, an air matching layer and a gradual change section cavity, the porous material layer is connected with the surface, closest to sound wave incidence, of the shell, the air matching layer is located between the porous material layer and the gradual change section cavity, and the sectional area of the gradual change section cavity is gradually increased in the sound wave incidence direction. The thickness of the low-frequency sound absorption device does not exceed 650 mm, the low-frequency sound absorption device is high in aerodynamic noise absorption coefficient at the low frequency band of 50-200 Hz, has excellent high-temperature resistance, can stably operate in the working environment of 150 DEG C or above, and meets the strict working conditions of a wind tunnel laboratory.

The invention discloses intelligent sound equipment, and relates to the technical field of sound equipment, the intelligent sound equipment comprises a shell, a first partition plate, a second partition plate, a high-frequency loudspeaker, a full-frequency loudspeaker and a radiation unit, and the shell is provided with an accommodating cavity; the first partition plate and the second partition plate are arranged in the containing cavity at intervals so as to divide the containing cavity into a high-frequency cavity, an intermediate-frequency cavity and a low-frequency cavity which are sequentially arranged, the size of the high-frequency cavity is smaller than that of the intermediate-frequency cavity, the size of the intermediate-frequency cavity is smaller than that of the low-frequency cavity, and the high-frequency loudspeaker is arranged in the high-frequency cavity. The full-frequency loudspeaker is arranged in the intermediate-frequency cavity, the second partition plate is provided with a frequency division unit communicated with the intermediate-frequency cavity and the low-frequency cavity, the frequency division unit is used for scattering and absorbing medium-high frequency sound waves and keeping propagation of low-frequency sound waves, and the radiation unit is arranged in the low-frequency cavity; the radiation unit is used for receiving low-frequency sound waves which are emitted by the full-frequency loudspeaker and are transmitted to the low-frequency cavity through the frequency division unit so as to enhance low-frequency response.

The invention discloses an energy storage safety early warning system of a smart power grid, and relates to the technical field of smart power grids, the system comprises a parameter acquisition module, a data preprocessing module, a fusion analysis module, a dynamic threshold adjustment module and an early warning output module; multi-mode physical parameters of vibration frequency, sound characteristics and electromagnetic field change of the energy storage equipment are introduced, traditional temperature and electric quantity parameters are combined, comprehensive and deep monitoring of the operation state of the equipment is achieved, the analysis mode of multi-parameter fusion not only enriches data dimensions, but also improves the reliability of the equipment. Meanwhile, by means of the artificial intelligence algorithm, the early warning threshold value can be dynamically adjusted according to equipment operation data and environment data which are collected in real time, so that the method can be more flexibly adapted to changes of the equipment operation state, and the comprehensive and accurate equipment state evaluation and early warning mechanism can be used for improving the accuracy and reliability of equipment state evaluation. And a powerful guarantee is provided for safe operation of an intelligent power grid.

The present disclosure related to a method of using high frequency sound waves directed toward an acoustically active particle. The high frequency sound waves may be configured to enlarge the acoustically active particle and oscillate the acoustically active particle, thereby facilitating extravasation of an agent to a tissue compartment of a region of interest.

A method and a system for improving the low-frequency sound reproduction of an audio signal, the sound reproduction being performed by an audio system comprising at least one loudspeaker. The system includes a low-frequency sound enhancement module with filters for separating an input audio signal into a high-frequency signal and a low-frequency signal. The system is configured to implement a first audio processing of the low-frequency signal to obtain a low-frequency output signal and a second audio processing of the high-frequency signal to obtain a high-frequency output signal. The low-frequency sound enhancement module includes, for the first processing of the low-frequency signal, a module for increasing the dynamic range of the low-frequency signal, which is parameterised as a function of at least one transient part of the low-frequency signal.

The invention relates to the technical field of sound absorption composite materials, in particular to a porous composite material capable of enhancing sound absorption performance and a preparation method and application of the porous composite material capable of enhancing the sound absorption performance. And high-efficiency sound absorption can be realized in the full frequency band of 100Hz-6000Hz. Especially in the low-frequency band of 200Hz-1000Hz, the sound absorption coefficient is increased by 20%-50% compared with that of a traditional porous material with similar thickness and weight, and the problem that the traditional material is insufficient in low-frequency sound absorption is solved.

The invention discloses a focusing type acoustic streaming heat dissipation device facing a chip. The device belongs to the crossing field of ultrasonic technology and heat dissipation technology and is composed of a piezoelectric stack, an acoustic lens, a splitter plate, a base, a supporting rod, a copper electrode and the like. According to the device, geometric parameter configuration of the splitter plate, the piezoelectric stack and the acoustic lens is optimized, and a double-piezoelectric-plate stacked structure is adopted to enhance the ultrasonic resonance effect; high-frequency alternating voltage is applied to the copper electrodes at the two ends of the piezoelectric stack, high-frequency sound waves are excited through the inverse piezoelectric effect, and after the sound waves are focused through the sound lens, a gradient sound pressure field is formed in a cavity formed by the splitter plate and the piezoelectric stack; air molecules are driven to move directionally based on the acoustic streaming effect, so that air flow at an air inlet is accelerated by sound pressure to form high-flow-rate focusing jet flow at an air outlet, and targeted forced convection heat dissipation of a chip heat source is realized. According to the device, the ultrasonic technology and the heat dissipation technology are combined, the whole device is simple in structure, free of moving parts and low in noise, and various heat dissipation requirements can be met in an array mode.

The invention relates to the technical field of material performance detection, and discloses a non-destructive evaluation method and system for the strength of microorganism mineralized river sand, and the method comprises the following steps: applying a sweep frequency sound wave excitation signal to a microorganism mineralized river sand standard sample model; performing penetration simulation operation on the microorganism mineralized river sand standard sample model according to the sweep frequency sound wave excitation signal; extracting mineralization specific characteristic parameters corresponding to the sample model through the penetration response signal; according to the mineralization specificity characteristic parameters, constructing a biological cementation index of microorganism mineralization, and according to the biological cementation index, analyzing the compressive strength of the microorganism mineralization river sand standard sample model; constructing a destructive calibration curve of the microorganism mineralized river sand standard sample model; the target compressive strength of the to-be-tested sample model is analyzed through the destructive calibration curve, and the strength non-destructiveness of the microorganism river sand corresponding to the to-be-tested sample model is analyzed based on the target compressive strength. According to the method, the accuracy of non-destructive evaluation of the strength of the microorganism mineralized river sand can be improved.

The invention provides lightweight sound-absorbing mute cotton and a preparation method thereof, the lightweight sound-absorbing mute cotton is of a bionic gradient structure and is divided into three layers, the bottom layer dissipates high-frequency sound waves, the middle layer optimizes intermediate-frequency resonance, and the upper layer enhances low-frequency sound wave scattering. The preparation method comprises the following steps: respectively preparing bottom-layer slurry, middle-layer slurry and upper-layer slurry; pre-cooling the bottom of a mold, and carrying out synchronous three-layer co-injection molding on the three kinds of slurry: carrying out one-way freezing to form a longitudinal gradient aperture; freezing and drying to obtain a three-layer gradient structure material; immersing in a graphene oxide quantum dot ethanol solution for vacuum treatment; heating, adding ascorbic acid, keeping for 2 hours, and applying 0.5% pre-strain to the material; photo-thermal curing is performed; and performing hot-pressing shaping to obtain the product. The gradient structure design is adopted, and the aperture, the fiber distribution and the filler type are regulated and controlled, so that acoustic impedance gradient change is realized, sound wave reflection is reduced, and the sound absorption efficiency is improved.

The invention provides a far-field sound source localization method applied to a transformer substation, and relates to the field of sound source localization, and the method comprises the steps: obtaining a target frequency sound in the transformer substation, and converting the target frequency sound into a spherical harmonic domain multi-channel observation vector; inputting the spherical harmonic domain multichannel observation vector into a preset network model to obtain a spherical harmonic domain mask matrix, and obtaining an in-band smooth covariance based on the spherical harmonic domain mask matrix; the preset network model is used for filtering the spherical harmonic domain multi-channel observation vector; according to the in-band smooth covariance, a spatial spectrum matrix is obtained, and the spatial spectrum matrix comprises spatial spectrum values in different candidate sound source directions; performing multi-sound source distinguishing on the spatial spectrum matrix to obtain a multi-source direction set, and realizing far-field sound source positioning of the transformer substation; the multi-source direction set comprises polar angle and azimuth angle coordinates of each target sound source direction and is used for reflecting the sound source direction in the transformer substation. The method solves the problems that the noise interference of the transformer substation is large and multiple sound sources are difficult to distinguish, and realizes the accurate positioning of the sound sources in the transformer substation.

The invention discloses a neck embedded ring type Helmholtz resonator, which relates to the technical field of low-frequency sound absorption structures and comprises a resonator main body, an embedded neck and a porous material lining. The resonator main body comprises an outer wall surface and a closed cavity; the embedded neck part penetrates through the top wall surface of the main body and comprises a neck part wall surface and an internal periodic convex ring structure; the porous material lining is attached to the inner wall of the closed cavity, and a first gap is formed between the porous material lining and the wall face of the neck. According to the resonator, the sound energy dissipation capacity and parameter harmonility are improved through the neck circular ring, the low-frequency sound absorption capacity is enhanced through the porous material in the cavity, the sound absorption peak value and frequency can be regulated and controlled by adjusting the parameters of the neck and the circular ring and selecting the type of the porous material, and the resonator is simple in structure, wide in application and beneficial to production.

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

The invention discloses a fish repelling method and system based on multi-frequency sound wave cooperation and dynamic environment perception. The method comprises the steps that water area environment parameters are acquired, and the types and the density of fishes in the water area are recognized through sonar, water velocity and water quality parameters; matching an auditory sensitive frequency band set according to the fish species, and constructing a multi-frequency-band sound wave emission parameter set in combination with the water area environment parameters; according to the sound wave emission parameter set, the transducer array is controlled to emit a multi-band composite sound wave signal, and a sound field with a coverage angle of at least 180 degrees is formed; and monitoring the driving effect in real time, and dynamically adjusting the multi-band sound wave emission parameter set according to the density change of the fish school. According to the method, the fish repelling efficiency can be remarkably improved, the influence on non-target species is reduced, and an innovative solution is provided for ecological protection of water conservancy projects.

The invention relates to the technical field of underwater low-frequency sound insulation superstructures, and discloses a pressure-resistant underwater low-frequency sound insulation superstructure based on a TPMS (Tire Pressure Monitor System) and a design method thereof, a two-dimensional section cell is intercepted and obtained on a Gyandroid lattice cell model along a sound wave incidence direction, and the characteristic that the modulus in the sound wave incidence direction is reduced and is easy to deform is utilized, so that the sound insulation performance of the sound insulation superstructure is improved, and the sound insulation performance of the sound insulation superstructure is improved. Low impedance is realized; the internal structure distribution of the cells is changed through stretching, so that the cells have anisotropy, the modulus of the cells in the sound wave incidence direction is reduced, and the impedance is further reduced; by introducing a material main shaft deflection angle, quasi longitudinal waves and quasi transverse waves in the structure are excited, and the longitudinal waves incident in water are converted into transverse waves in the structure through longitudinal-transverse wave conversion, so that the sound insulation performance is improved; performing periodic array arrangement, intercepting to obtain a core layer configuration under a two-dimensional plane, and performing structure materialization to obtain a sound insulation layer; the two sides of the sound insulation layer are covered with cover plates, and the pressure-resistant underwater low-frequency sound insulation superstructure based on the TPMS is obtained.

The invention relates to the field of noise reduction control of power equipment, in particular to a corrugated composite silencer used for reducing low-frequency noise in a transformer. The corrugated composite silencer structurally comprises a corrugated expansion cavity, a high-frequency sound absorption layer, a backflow cavity, an internal perforated plate and a hard wall, the corrugated expansion cavity is a main body part of the silencer and is directly connected with the inlet side and the outlet side of the silencer; the high-frequency sound absorption layer is attached to the outer side of the corrugated expansion cavity and is separated from the corrugated expansion cavity by an internal perforated plate; the backflow cavity is located on the outer side of the high-frequency sound absorption layer and is separated from the high-frequency sound absorption layer through a hard wall and an internal perforated plate. Wherein the corrugated expansion cavity adopts a corrugated wall surface and is used for improving the equivalent acoustic impedance of the silencer structure and improving the low and medium frequency noise reduction effect of the silencer; the high-frequency sound absorption layer is filled with high-frequency sound absorption materials such as glass fiber cotton so as to improve the medium-high frequency noise reduction capacity of the structure. And the backflow cavity is used for specifically absorbing noise with specific frequency at low and medium frequencies. The corrugated wall surface is combined with the backflow cavity, the corrugated composite silencer structure for low-frequency noise reduction in the transformer is designed, and the actual noise reduction requirements of most transformers can be met.

The invention provides a broken thick and large ore body continuous tunneling and filling mining method, and relates to the technical field of mining engineering.The method comprises the steps that the rock mass grade is determined through rock mass basic quality indexes, the single tunneling circulating footage and the top temporary supporting grade are matched, and in a set monitoring window, the current circulating section is subjected to continuous tunneling and filling mining; geological radar waves and short-range low-frequency sound waves are emitted to the top plate at equal time intervals, the proportion of high-frequency signals and the sound wave propagation speed are calculated, surrounding rock deformation section data, the change degree of two indexes and the DTW distance of continuous two-time radar wave reflection signals are comprehensively analyzed at each monitoring moment, and whether the surrounding rock deformation section data, the change degree of the two indexes and the DTW distance are abnormal or not is judged; if no abnormity exists, radar wave reflection signals are stored as standard templates according to the rock mass grade, and when the number of the standard templates is smaller than N, the data and a preset threshold value optimize the supporting grade; when the number of the templates is not smaller than N, the index mean value and the standard deviation update threshold value are counted according to monitoring moment grouping, and the top temporary support grade is optimized.

The invention relates to the field of voice recognition, in particular to an industrial field high-frequency voice recognition method and a storage medium. The method comprises the following steps: performing short-time Fourier transform on an industrial field sound signal by using a double-branch window to obtain a double-branch spectrogram; performing channel stacking on the double-branch spectrogram to obtain a three-dimensional tensor; after the extracted features are classified and calculated, a classification head outputs score vectors of probability scores of three dimensions of target sound, environment sound and strong noise; softening the probability score by using a temperature coefficient, and inputting the softened probability score into a classification function to obtain probability distribution; and calculating an energy score, when the energy score is lower than a preset energy threshold value, calculating an attenuation coefficient to carry out scaling suppression on the probability distribution to obtain final probability distribution, judging whether the highest value in the final probability distribution is lower than a rejection threshold value or not, and obtaining an identification result. According to the method, the fault sound detection rate is greatly improved in industrial actual measurement, and the false alarm rate is remarkably reduced.

The invention discloses a coal bed gas exploitation and separation utilization method based on SCCO2 assistance, and belongs to the technical field of coal bed gas development. Supercritical carbon dioxide is prepared through a high-pressure reaction kettle and stored in a supercritical carbon dioxide storage and collection tank, meanwhile, nitrogen mixed with graphene is introduced, and CO2 / CH4 adsorption selectivity is enhanced by means of the characteristic that the specific surface area of graphene is large. A variable-frequency sound wave diffuser is matched to excite coal seam micro cracks through low-frequency sound waves, and supercritical carbon dioxide and nitrogen mixed gas is injected into a coal seam injection well. In the injection process, the sound wave diffuser synchronously radiates high-frequency sound waves to improve the displacement efficiency, then the gas enters the gas separation tower integrated with the molecular sieve membrane, and the produced gas is divided into upper methane, middle carbon dioxide and other bottom miscellaneous gas. Methane is pressurized by an air compressor and then stored in a methane storage tank, carbon dioxide is purified and pressurized and then recycled for coalbed methane exploitation, and offensive gas is cooled and stored after generating power by a steam turbine. And efficient mining, separation and multi-path utilization of the coal bed gas are realized.

The invention relates to a multi-physical mechanism synergistic light sound absorption and insulation integrated sandwich structure and a manufacturing method thereof.The multi-physical mechanism synergistic light sound absorption and insulation integrated sandwich structure comprises a panel, a sandwich layer and a micro-perforated panel which are arranged from top to bottom, a cavity is formed in the sandwich layer, and multiple sets of cantilever beam type harmonic oscillators arranged in an array are arranged in the cavity; the cantilever beam type harmonic oscillator comprises a cantilever beam base body and a metal rubber mass block fixed at the top end of the cantilever beam base body. According to the invention, through the coupling design of the micro-perforated plate and the internal grating cavity of the sandwich layer, the sound absorption frequency band is further widened, the sound absorption coefficient of the whole structure in a middle-high frequency band is improved, collaborative optimization of broadband sound absorption and low-frequency sound insulation is realized, the problem that a traditional harmonic oscillator is easy to lose efficacy in high-temperature and low-temperature environments is effectively solved, and the sound absorption efficiency is improved. And meanwhile, due to the design of the integrated sandwich structure, the problems of aging and layering of the adhesive layer in severe environments such as high temperature and damp and hot environments are avoided, and the integrity and durability of the structure are also remarkably improved.

The invention relates to the technical field of sound absorption, in particular to a bionic low-frequency sound absorption structure, a sound absorption device and a low-frequency noise control method.The bionic low-frequency sound absorption structure comprises a plurality of bionic resonance units, the bionic resonance units are hollow tubular bodies extending in the axial direction, and through holes are evenly formed in the tube walls in the axial direction and the circumferential direction; the plurality of bionic resonance units are arranged in parallel and tightly attached; structural parameters of the bionic resonance unit are bionic to measured data of a noctuid wing seta prototype structure, and are determined according to proportional amplification based on a structural vibration similarity principle. Decoupling of the structure scale and the sound wave wavelength is achieved through a bionic amplification strategy, and low-frequency sound waves can be effectively absorbed under the condition of small thickness; the dependence on a porous material is eliminated, and the problems that a fiber material is easy to age and poor in weather resistance are solved; the defects that a traditional resonance structure is narrow in frequency band and poor in adaptability are overcome, excellent broadband sound absorption characteristics and structural robustness are achieved, and effective control over low-frequency noise can be achieved.