70 results about "Frequency sound" patented technology

This utility model relates to the field of sound insulation technology, and discloses a soundproof shell and air conditioning unit, including a shell, a rubber damping layer disposed on the inner side of the shell, and a low-frequency sound-absorbing layer and a high-frequency sound-absorbing layer. By placing the low-frequency sound-absorbing layer between the rubber damping layer and the high-frequency sound-absorbing layer, this utility model allows the rubber damping layer to buffer low-frequency vibrations during air conditioning unit operation, reducing the low-frequency vibration energy transmitted to the shell and lowering low-frequency noise generation. The low-frequency sound-absorbing layer, positioned adjacent to the rubber damping layer, can promptly receive and absorb the low-frequency vibration energy buffered by the rubber damping layer, resulting in more thorough low-frequency noise reduction and improving the overall noise reduction effect of the soundproof shell. This effectively prevents the shell from vibrating and amplifying low-frequency noise. Simultaneously, the high-frequency sound-absorbing layer absorbs and blocks high-frequency noise, ensuring that noise in different frequency bands (low, medium, and high) is effectively absorbed and blocked.

This invention provides a multi-layered lightweight sound-absorbing and insulating material, comprising a layer of sound-absorbing cotton, a cup-shaped plastic film layer, and a plastic board layer stacked together. Multiple cup-shaped structures are arranged in an array on the cup-shaped plastic film layer. Each cup-shaped structure has a second through-hole at its bottom, and these structures are arranged periodically according to the size of the second through-hole. Within each arrangement cycle, there are multiple second through-holes with different diameters. The cup-shaped structures corresponding to the different diameters of the second through-holes form multiple Helmholtz resonators with different resonance frequencies. This invention forms multiple Helmholtz resonators with different resonance frequencies through multiple cup-shaped structures with different through-hole diameters. The coupling effect of the perforated cup-shaped structures with different resonance frequencies generates a continuous and wide mid-to-low frequency resonant sound-absorbing band. While possessing a certain high-frequency sound absorption capability, it significantly improves the low-to-mid frequency sound absorption and insulation capability. Compared with traditional porous sound-absorbing materials such as felt fibers and sound-absorbing cotton, it greatly improves the sound absorption and insulation capability at the same thickness.

A composite sound-absorbing silencer includes: a low-frequency sound-absorbing module and a mid-to-high-frequency sound-absorbing module installed inside the ventilation opening of a substation; the low-frequency sound-absorbing module adopts an internal tube superstructure design to absorb noise in the first frequency band radiated from the transformer body; the mid-to-high-frequency sound-absorbing module absorbs noise in the second frequency band radiated from the transformer body through frictional loss; the frequency of the first frequency band noise is lower than the frequency of the second frequency band noise. This invention can adjust the usable area and arrangement of the internal modular low-frequency sound-absorbing modules according to the actual cross-sectional area of ​​the ventilation opening and the environmental ventilation requirements, thereby controlling the radiated noise from the transformer in the indoor substation; the product has the lowest pressure loss along the entire airflow path, improving the cooling safety and reliability of the equipment operation; and by installing a wire mesh at the silencer's air inlet, it strengthens the protection against external objects and extends the service life of the equipment.

This invention discloses a method and system for soil moisture content inversion based on multipath low-frequency acoustic waves and deep learning. The method is applied to a soil moisture content detection system. The system includes a central control module, a low-frequency acoustic wave transmitting module, an acoustic wave receiving and amplifying module, a multi-channel remote communication module, and a data processing and inversion module. The method includes: the central control module controlling the transmitting module to transmit multipath low-frequency analog acoustic wave signals and recording the transmission parameters; the receiving module receiving the acoustic wave signals passing through the soil, amplifying and converting them from analog to digital before uploading them to the central control module; the central control module calculating acoustic features and sending them to the data processing module; the data processing module extracting acoustic feature parameters and constructing spatial location information based on the acoustic wave rays, and using a deep neural network to invert and obtain the two-dimensional spatial distribution of soil moisture content. This invention achieves effective detection of regional soil moisture content, with high detection accuracy and engineering applicability.

The application belongs to the technical field of electro-acoustic conversion equipment, and particularly relates to a replaceable-line high-fidelity noise-reducing in-ear earphone based on a floor iron moving unit, which comprises a 5-unit 4-frequency division hybrid driving module formed by the floor iron moving unit and a micro moving coil unit, and the two achieve signal cooperation through a phase synchronization circuit; full-frequency sound quality optimization and hybrid noise reduction are achieved through the phase synchronization circuit and a DSP+ANC chip, a sound cavity is matched with a shape memory alloy damping adjusting sheet, magnetic attraction and sealing of a 2-pin interface improve durability and sealing performance, a double-mode switching audio line and a three-in-one replaceable plug adapt to multiple devices, and touch control and a selectable Bluetooth kit realize convenient interaction. The application breaks through the sound quality limitation of a single unit through a double-unit cooperative driving structure, realizes dynamic adaptation of noise reduction and sound quality through an adaptive acoustic adjusting system, improves durability and personalized upgrade space through a reinforced replaceable line design, enriches use scenarios through an intelligent interaction module, and meets the multiple needs of high-end users for high-fidelity sound quality, flexible use and intelligent experience.

The invention belongs to the technical field of acoustic metamaterials, pipeline noise control and aeroacoustics, and discloses a compact broadband anti-flow sound absorption structure and a preparation method thereof.The broadband anti-flow sound absorption structure comprises a resonance body and a flow resistance control interface layer arranged on the incident plane of the resonance body, the resonance body comprises a sound absorption unit, and the flow resistance control interface layer is arranged on the incident plane of the resonance body; each sound absorption unit comprises a first cavity and a second cavity, a first micro-tube array is arranged in the first cavity, a second micro-tube array is arranged in the second cavity, the first micro-tube array comprises an upper panel and a first embedded micro-tube, the second micro-tube array comprises a partition plate and a second embedded micro-tube, the first embedded micro-tube extends towards the interior of the first cavity, and the second embedded micro-tube extends towards the interior of the second cavity. The second embedded microtube extends into the second cavity, an interface gap is formed between the flow resistance control interface layer and the upper panel, and the interface gap is located between the flow resistance control interface layer and an inlet of the first microtube array. The invention has the advantages of compact structure, broadband low-frequency sound absorption, glancing loss resistance, suitability for additive manufacturing and the like.

This application discloses a diesel vehicle exhaust particulate separation device and dynamic optimization method based on a dual-frequency sound field. The device has a dual-frequency broadband sound source installed at the inlet of the separation chamber and a dual-wavelength laser monitoring component installed at the outlet, directly connected to the vehicle's CAN bus via a controller. Overcoming the lag of traditional single-frequency blind scanning, it proposes a feedforward initial frequency-feedback frequency modulation closed-loop control strategy: millisecond-level feedforward initial frequency preset is achieved by analyzing engine speed and load signals using a programmed MAP library; red and blue dual-wavelength lasers are used to track the transmittance changes of large and small particles respectively, and a fractional-order update law with an anti-overshoot exponent is introduced to perform microsecond-level dynamic closed-loop optimization of the sound frequency; the power of the fundamental frequency and high-frequency harmonics is dynamically allocated according to the differences in particle concentration of different particle sizes. It possesses functions of prior perception, rapid response, and prevention of getting trapped in local optima, improving the separation efficiency of a wide range of particulate matter of all sizes and effectively reducing the risk of clogging and replacement cycle of particulate filters.

The application relates to a moving-coil low-frequency sound source active pressure compensation closed-loop control system and method, which measures the amount of the sound source radiation surface deviating from the balance position through a displacement sensor, adjusts the gas flow direction, controls the gas amount in the sound source radiation cavity space, always maintains the radiation surface at the balance position, realizes active compensation control of the gas pressure, and makes the gas pressure in the sound source radiation cavity always equal to the ambient water pressure. The application realizes the balance between the pressure in the internal cavity of the sound source radiation surface and the external water pressure, and realizes closed control of pressure regulation through the gas circulation mode.

The application discloses a four-fingered tetra intelligent net cage breeding system and method based on behavior recognition and low stress control, which comprises a flexible anti-collision light-blocking net cage module, an underwater AI behavior early warning module, a micro-bubble and sound-light soothing intervention module and a dry-free flexible transfer module. The flexible anti-collision light-blocking net cage eliminates net collision and scale shedding and visual disturbance from the physical structure, the underwater AI behavior early warning module extracts three-dimensional features of sudden change rate of swimming speed, spatial dispersion and gill cover vibration frequency to calculate a comprehensive stress index, realizes four-level grading early warning, the micro-bubble and sound-light soothing intervention module realizes targeted soothing through mute oxygenation, blue-green light and low-frequency sound waves, and the dry-free flexible transfer module realizes underwater zero-fishing transfer of fish bodies. The application improves the survival rate of four-fingered tetra by 22.6% and reduces the scale infection rate by 93.5%, solves the stress bottleneck of large-scale breeding of the four-fingered tetra and is suitable for large-scale near-shore net cage breeding of the four-fingered tetra.

The application relates to a bistable SR system and a low signal-to-noise ratio multi-frequency sound signal detection device and method. By introducing an optical fiber device, the closed-loop regulation of the optical fiber grating is utilized to realize the random resonance phenomenon based on the bistability, and the low signal-to-noise ratio signal can be effectively extracted under the strong noise background. Secondly, by introducing a carrier signal, the difference frequency signal is obtained by mixing with the external signal, and the multi-frequency signal sensing is realized under the premise of fixing the detection range of the difference frequency signal. In addition, by introducing the array structure of the optical fiber hydrophone, the spatial gain is formed, and the high-sensitivity detection effect can be realized. Finally, the frequency distribution and the relative signal-to-noise ratio intensity size distribution of the obtained target sound signal can be used as the input of the neural network model, the intelligent identification of the low signal-to-noise ratio target sound target is realized, and the detection and early warning of the underwater target can be maximally realized.

This invention discloses a planar membrane mass transfer internal component, a collection tower, and a collection system based on sound field enhancement. The planar membrane mass transfer internal component includes several vertically arranged resonant composite plates and a support assembly for supporting the resonant composite plates. The resonant composite plates are layered structures with double-sided mass transfer, comprising, from the inside out, a piezoelectric transducer array layer, an acoustic impedance matching layer, and a hydrophilic microporous mass transfer layer. The piezoelectric transducer array layer is electrically connected to a power supply to generate high-frequency mechanical vibration, thereby forming a high-frequency sound field. The support assembly includes several limiting grooves located above and below the resonant composite plates, and a frame for fixing the limiting grooves. The resonant composite plates are floatingly installed within the limiting grooves, with their upper and lower ends forming a limiting fit with the limiting grooves. This invention significantly improves mass transfer efficiency by disrupting the boundary layer of high-viscosity liquid films at the microscale using active sound field technology, and solves the problem of fixing and damping piezoelectrically brittle components in industrial towers by employing a floating installation structure.

The utility model provides a kind of curtain wall inner aluminium veneer, including plate body, the back of plate body is with outer frame, a plurality of eyelet is opened in plate body, the outermost layer of plate body itself is lacquer layer, the back surface of plate body, the inside of outer frame is coated with a coating;The back of plate body is fixedly connected with two reinforcing ribs, and the four point positions of outer frame are fixedly connected with corner code.The utility model has the advantages that: plate body back and outer frame inside are coated with a coating, coating is polyurethane damping adhesive layer, reduce plate resonance;The free space of coating surface, paste a sound-absorbing layer, match different frequency sound wave absorption;The front and back of corner code are attached with pad, and pad is made of rubber, metal and rubber, to prevent noise generated by friction after aluminium plate mounting connector component;The above means can make the present aluminium veneer after installation, with certain noise reduction and sound insulation performance, effectively ensure the low-noise environment of building indoor, ensure the clean of indoor environment.

The application discloses a loudspeaker assembly and earphone, which comprises a shell assembly, an air-conduction loudspeaker and a bone-conduction loudspeaker. The shell assembly is provided with a containing space. The air-conduction loudspeaker is arranged in the containing space. The bone-conduction loudspeaker is arranged in the containing space. The shell assembly is further provided with a sound outlet hole and a pressure relief hole which are communicated with the containing space. The sound outlet hole and the pressure relief hole are respectively used for conducting part of sound waves generated by the air-conduction loudspeaker to the external environment. The pressure relief hole and the sound outlet hole are respectively located on two opposite side surfaces of the shell assembly. In this way, the application can reduce the mutual influence between the sound waves conducted by the sound outlet hole and the sound waves conducted by the pressure relief hole, improve the low-frequency sound quality and improve the sound quality effect.

This invention relates to a low-frequency sound pressure level (SPL) enhancement speaker enclosure and its cabinet. The enclosure includes a speaker enclosure and a subwoofer. The enclosure has a cavity and a subwoofer output, which consists of a mounting port and a sound wave radiation window. The mounting port and the sound wave radiation window connect the cavity to the outside environment, and are completely separated on the enclosure. The subwoofer is mounted in a sealed manner on the enclosure through the mounting port and generates low-frequency reverse waves radiating into the cavity during vibration. These reverse waves are then radiated into the outside air through the sound wave radiation window. In this invention, sound waves within the enclosure cavity can be radiated into the outside air through the sound wave radiation window, allowing sound waves behind the speaker to be utilized, thereby enhancing the low-frequency SPL and improving sound quality. This low-frequency SPL enhancement speaker enclosure is characterized by its simple structure, ease of acoustic parameter adjustment, and low cost.

This invention provides a gradient helical tube composite Helmholtz resonator sound absorption device and its adjustment method, relating to the field of noise control technology. It solves the problem of existing technologies' difficulty in simultaneously achieving high low-frequency efficiency and broadband sound absorption within a limited space. The gradient helical tube composite Helmholtz resonator sound absorption device includes a gradient helical tube and multiple Helmholtz resonator units. The diameter of the gradient helical tube changes continuously along the sound wave propagation path. The multiple Helmholtz resonator units are connected in series at the ends of the gradient helical tube and disposed within the internal space enclosed by the gradient helical tube. This invention can broaden the sound absorption bandwidth and enhance low-frequency sound absorption performance through the composite structure of the gradient helical tube and multiple Helmholtz resonator units.

A method for measuring the thickness of a braking component in a brake assembly for a heavy vehicle, wherein the brake assembly for a heavy vehicle comprises a braking element including a friction material having an engagement surface, and the braking element is configured to decelerate the heavy vehicle by engaging the engagement surface of the friction material with the braking surface of the braking component when actuated during braking. The method includes determining whether an ultrasonic device having an ultrasonic emitter is in an engaged state, in contact with the braking surface; when the ultrasonic device is in an engaged state, emitting high-frequency sound waves through the braking component with the ultrasonic emitter, detecting the high-frequency sound waves with an ultrasonic sensor; and calculating the thickness of the braking component based on the time delay between the emission and detection of the high-frequency sound waves.

This application relates to the field of semiconductor technology, specifically to a MEMS piezoelectric loudspeaker and acoustic device, including a substrate and a piezoelectric stack disposed on the substrate; the piezoelectric stack has multiple tangents extending from the geometric center of the piezoelectric stack to the edge of the piezoelectric stack, forming multiple cantilever beams arranged rotationally symmetrically about the geometric center; each cantilever beam has a fixed edge away from the geometric center; at least two of the cantilever beams have trench structures on the substrate, the trench structures being located close to the fixed edge of the cantilever beam. This application can reduce peaks at resonant frequencies and effectively expand the frequency bandwidth, improving overall audio performance; in addition, this application can also reduce diaphragm stiffness, thereby significantly enhancing its low-frequency deformation capability and optimizing the low-frequency sound pressure level curve.

A dual-mode audio coding system and a dual-mode audio coding method are provided in the embodiments of the present invention. The system includes a signal transmission device and a signal reception device. The transmission device comprises a first control circuit and a sound circuit, where the sound circuit incorporates a sound diaphragm and an electromagnetic coil. Based on the instructions from the first control circuit, it emits audio sound waves and high-frequency sound waves while transmitting electromagnetic signals through the coil, with the frequency of the high-frequency sound waves being higher than that of the audio sound waves. The reception device consists of a second control circuit, a sound reception circuit, and an electromagnetic reception circuit, which are used to receive audio and high-frequency sound waves as well as electromagnetic signals. The first control circuit modulates communication signals into high-frequency sound waves and electromagnetic signals, while the second control circuit demodulates the received signals to reconstruct the original communication signals.

This invention discloses a method for preparing a magnesium cementitious material with good mid-frequency sound absorption effect, comprising the following steps: (1) dissolving magnesium sulfate heptahydrate and an additive in water under heating conditions to obtain a mixed solution; (2) mixing lightly calcined magnesium oxide, a foam stabilizer, a water-reducing agent, and a catalyst, and stirring thoroughly to obtain a mixed material; (3) mixing the mixed solution from step (1) with the mixed material from step (2), and stirring thoroughly to obtain a uniform slurry; (4) adding hydrogen peroxide to the slurry from step (3), stirring thoroughly, and then pouring it into a mold; placing the mold on a frozen copper column, placing a heating plate on the upper surface of the mold, and simultaneously heating and freezing; (5) after the slurry has initially solidified, subjecting it to standard air curing to obtain a magnesium cementitious material. The magnesium cementitious material prepared by the method of this invention has a gradient pore structure inside and has a sound absorption coefficient of up to 0.96 for mid-frequency noise (500–800 Hz).

The application discloses a design method and device of a low-frequency transducer, and the method comprises the following steps: obtaining specification size information and detection characteristics of a sonic logging instrument; the specification size information comprises geometric size parameters and environmental tolerance parameters; the detection characteristics comprise measured sound wave types and detection depths; determining the size of a single piezoelectric ceramic sheet in the low-frequency transducer of the sonic logging instrument according to the specification size information; determining the working frequency band of the low-frequency transducer according to the detection characteristics; determining the number of piezoelectric ceramic sheets in the low-frequency transducer according to the working frequency band; and obtaining the design scheme of the low-frequency transducer of the sonic logging instrument according to the size, the number and a preset piezoelectric ceramic sheet physical connection mode. The application can meet the excitation demand of low-frequency sound waves.

This invention discloses a design method for a multi-layer composite sound-insulating superstructure. The multi-layer composite sound-insulating superstructure is designed as an upper and lower substrate and a rectangular frame. Multiple resonators (Type 1 and Type 2) are respectively disposed on the upper and lower substrates, forming a single-layer superstructure material plate. The rectangular frame is filled with porous sound-absorbing material, with multiple upper and lower holes respectively opened on the upper and lower surfaces of the porous sound-absorbing material. The upper substrate is in contact with the upper surface of the rectangular frame, and the lower substrate is in contact with the lower surface of the rectangular frame. Multiple resonators (Type 1) are inserted into multiple upper holes, and multiple resonators (Type 2) are inserted into multiple lower holes. The two single-layer superstructure material plates are stacked to form a composite superstructure. The composite superstructure utilizes the phase cancellation of sound radiation at the anti-resonance frequency to form a sound insulation peak exceeding the mass law curve, thereby improving the sound insulation performance at mid-to-low frequencies. The internal porous sound-absorbing material further enhances the high-frequency sound insulation performance.

This invention provides a sound-generating device and an electronic device having the same. The sound-generating device includes: a body; a sound-generating assembly disposed within the body and including a first, a second, and at least a third speaker, wherein the first speaker is configured to output a full-frequency sound signal of a first channel, and the second speaker is configured to output a full-frequency sound signal of a second channel; the signal input terminal of the third speaker is connected in parallel with the signal input terminal of the first speaker to be configured to output a high-frequency sound signal of the first channel; and / or, the signal input terminal of the third speaker is connected in parallel with the signal input terminal of the second speaker to be configured to output a high-frequency sound signal of the second channel; and a frequency divider capacitor is connected in series with the signal input terminal of the third speaker to filter out at least a portion of the low-frequency sound signal entering the signal input terminal of the third speaker. This invention solves the problem that existing multi-speaker sound-generating schemes require the additional integration of Smartamp devices, which increases manufacturing costs and debugging complexity.

This utility model discloses a thermal insulation and soundproof floor slab structure based on microporous damping elastomer, relating to the field of floor slab structure technology, including a floor base layer and a thermal insulation and soundproof mechanism; the thermal insulation and soundproof mechanism includes an elastic thermal insulation and soundproof layer, a reinforcing protective layer, a protective layer, a finishing layer, vertical sound insulation sheets, and several sets of waterproof tapes connecting the elastic thermal insulation and soundproof layer and the reinforcing protective layer; the floor base layer, elastic thermal insulation and soundproof layer, reinforcing protective layer, protective layer, and finishing layer work together to enable the thermal insulation and soundproof floor slab structure to have good high-efficiency thermal insulation performance and multi-frequency sound insulation effect, and is easy to construct. Combined with vertical sound insulation sheets, the sound insulation effect is improved. The elastic core material and protective surface layer work together to give the elastic thermal insulation and soundproof board heat-reflective composite properties, stable mechanical properties, and strong adaptability, improving the compressive strength and impact resistance of the thermal insulation and soundproof floor slab structure.

This invention proposes a dynamic baffle speaker enclosure for enhancing sound energy, comprising a speaker unit, a speaker mounting plate, a speaker enclosure frame, a dynamic baffle, a suspension system, and a mechanical coupling component. The speaker unit includes a cone, a frame, and a magnetic circuit. The speaker mounting plate has sound-permeable holes, and the speaker unit's frame is fixedly mounted on the mounting plate. The speaker enclosure frame supports the speaker mounting plate. The dynamic baffle is located in front of the speaker unit. The suspension system connects the dynamic baffle to the speaker enclosure frame, allowing the dynamic baffle to vibrate and shift relative to the speaker enclosure frame. The mechanical coupling component connects the edge of the speaker unit's cone to the center area of ​​the dynamic baffle, transmitting the cone's vibration to the dynamic baffle. This invention directly transmits speaker vibration to the dynamic baffle through the mechanical coupling component, combined with the elastic support of the suspension system, significantly enhancing low-frequency sound wave radiation efficiency and solving the problems of insufficient low-frequency energy and poor transient response in traditional speakers.

This invention discloses a composite sound-absorbing structure based on acoustic black holes, comprising multiple coplanar acoustic black hole units containing nested Helmholtz resonators. Each unit includes multiple perforated plates connected in series and a Helmholtz resonator with a nested cavity connected to its end. This composite structure increases the equivalent acoustic cavity length through the nested cavity, significantly enhancing low-frequency sound absorption performance below 200Hz, achieving excellent subwavelength sound absorption characteristics while maintaining a compact thickness. Through parameter optimization of the unit coplanarity and target frequency band, the total thickness at the 86Hz sound absorption peak is approximately λ / 50, and an average sound absorption coefficient of 0.8604 within the 226–1000Hz range can be achieved with a total thickness of less than 70 mm. The nested cavity design improves acoustic control flexibility, enabling precise control of complex low-frequency broadband noise. It possesses advantages such as small size, wide bandwidth, and strong low-frequency absorption, making it suitable for high-end noise control fields such as aerospace and shipbuilding, with broad application prospects.

This invention discloses a mid-to-low frequency ventilation and sound insulation metamaterial comprising two main areas: sound absorption and ventilation. The sound absorption area is divided into inner and outer rings, each composed of multiple circumferentially arranged sound-absorbing functional cavities. Each functional cavity includes a resonant cavity formed by partitions and a perforated cavity formed by micro-perforated plates. The perforations on the plates are positioned according to the centroid of the vertical projection of the functional cavities. The ventilation area is a cylindrical region enclosed by the inner ring functional cavities, forming a complete resonant cavity via a ring-shaped base plate. This material combines the resonant characteristics of a Helmholtz resonator, achieving mid-to-low frequency broadband sound insulation through multiple parallel HR combinations. The hollow tube design ensures ventilation, and the mid-to-low frequency band utilizes a non-local coupling sound absorption mechanism for sound insulation. A 4.6cm thick specimen can block 90% of incident wave energy (TL≥10dB) in the 435~1700Hz range, and customized designs can be achieved simply by adjusting the aperture. The improved design incorporates a connecting small hole in the center of the inner and outer functional cavity partitions to form a connected functional cavity, bridging the gap between resonance absorption peaks and enhancing low-frequency sound absorption. The improved unit can achieve the same sound insulation effect in the range of 385~1700Hz.

This invention specifically relates to a method for analyzing the structural strength sensitivity of automotive generator assemblies. The method first constructs a finite element model of the generator assembly and calculates its unit radial and torsional stiffness coefficients; then, it constructs an acoustic simulation model and obtains a dataset of the full-frequency sound transfer function of the structural surface through full-band frequency sweep simulation; next, it calculates the single-frequency noise sensitivity coefficient and combines it with the stiffness coefficient to obtain the overall noise sensitivity coefficient; finally, it completes the sensitivity analysis and performance level assessment of the structural strength's impact on noise through preset rating rules. This invention eliminates the need for complex multi-physics coupling simulations and physical prototypes, enabling fully digital analysis and risk prediction to be completed early in the design process, significantly shortening the product development cycle and providing standardized support for low-noise forward design of generators.

This invention discloses an asynchronous measurement technique for 3D imaging of multi-point, non-planar low-frequency sound sources. It utilizes two 64-channel 3D spherical arrays for asynchronous measurement, proposing a unique dual-cylindrical spiral ascent and rotation movement method to achieve 3D point source imaging within low-frequency sound sources. This method differs from previous directional methods. It employs an asynchronous measurement technique involving the centers of two spherical arrays following a designed dual-cylindrical spiral parallel ascent trajectory and the array's rotation, applied to 3D imaging of multi-point, non-planar low-frequency sound sources. This results in a larger and denser array. To a certain extent, the asynchronous measurement method combining the dual-cylindrical spiral trajectory and rotation further improves the density of synthesized microphones compared to cylindrical trajectory asynchronous measurement methods and spherical array center revolution-rotation asynchronous measurement methods. The method is stable and efficient.

This invention discloses a maintenance method and system for activated carbon adsorption facilities based on lifetime prediction, belonging to the field of industrial equipment condition monitoring technology. The method includes: using an acoustic sensor array deployed in the activated carbon adsorption facility to emit high-frequency sound waves and receive response signals to acquire phonon spectrum data reflecting the lattice vibration of activated carbon; extracting multi-dimensional feature parameters from this data, and constructing a dynamically evolving phonon metabolic fingerprint through dimensionality reduction; performing decay analysis by combining the phonon metabolic fingerprint and real-time operating data to output a predicted value of the remaining lifetime; and finally implementing preventive maintenance based on the predicted value to achieve precise operation and maintenance of the activated carbon adsorption facility. This invention solves the technical problems of traditional maintenance methods relying on macroscopic parameters, low prediction accuracy, and inability to anticipate sudden failures, achieving the technical effect of accurate lifetime prediction and early warning of sudden risks for the operating conditions of activated carbon adsorption facilities.