626 results about "Noise control" patented technology

The invention relates to the technical field of vibration and noise control, discloses a new energy automobile motor high-frequency vibration and noise active suppression system and method, and aims to solve the problems of poor high-frequency vibration and noise suppression effect, real-time performance, adaptive capacity and system cost complexity of an existing new energy automobile motor. The method comprises the following steps: acquiring and preprocessing motor operation state data, extracting high-frequency harmonic characteristics, and generating predicted harmonic characteristics in combination with working condition prediction; and superposing the self-adaptive compensation quantity to a motor voltage instruction, and driving an inverter through pulse width modulation to realize active suppression of high-frequency vibration and noise. The system comprises a data acquisition preprocessing module, a harmonic feature extraction module, a working condition sensing prediction module, a self-adaptive compensation quantity generation module and a pulse width modulation correction module. By the adoption of the technical scheme, efficient, real-time and self-adaptive suppression of high-frequency vibration and noise of the motor can be achieved, the level of the high-frequency vibration and noise is remarkably reduced, the driving comfort is improved, and the complexity and cost of the system are optimized.

The invention relates to the technical field of aircrafts, and discloses a noise-considered urban low-altitude unmanned aerial vehicle path optimization method, which comprises the steps of urban environment rasterization and environment parameter setting; constructing an unmanned aerial vehicle noise attenuation model; calculating a noise interference critical distance and building sensitivity weight assignment; solving a noise interference grid matrix; a low-altitude unmanned aerial vehicle path planning model; and improving A * algorithm design. According to the method, the urban environment is rasterized, environmental parameters are set, an outdoor noise attenuation model is established by integrating geometric divergence, atmospheric absorption, ground effect and other factors, the propagation law of unmanned aerial vehicle noise in a complex environment is accurately described, the overall noise exposure and the sensitive area noise exposure are remarkably reduced while the flight safety is guaranteed, and the unmanned aerial vehicle noise attenuation performance is improved. The calculation efficiency is improved through the critical distance, path redundancy is avoided, collaborative optimization of noise control and operation efficiency is achieved, and technical support is provided for standardized operation of urban ultra-low-altitude unmanned aerial vehicles.

The invention relates to the field of aviation noise control, and provides an aircraft landing gear noise reduction device and method based on micro metal wire spiral winding. The device part comprises a metal wire and a metal wire fixing buckle, the metal wire is fixed through the metal wire fixing buckle, and meanwhile the size and material parameters of the metal wire are designed in a targeted mode. In the method part, the designed metal wire is wound on a cylindrical bluff body part, possibly generating vortex shedding and vortex-fixing interference, on the nose gear in a spiral winding manner, and the two ends and the axial interval position of the metal wire are fixed through the metal wire fixing buckles, so that the metal wire is ensured to be fastened. Therefore, through the wound metal wires, single-frequency noise in the over-top direction caused by falling of a towing rod vortex can be effectively eliminated, broadband noise is reduced, and the noise control capability of an airplane is improved. The method is suitable for various civil aircraft types, and has the advantages of being simple in structure, remarkable in noise reduction effect, high in practicability, high in adaptability and the like.

The invention provides a noise elimination structure, a compressor and an air conditioner, the noise elimination structure comprises a first noise elimination component which is detachably arranged on a mounting base, and at least part of the first noise elimination component is used for defining a first cavity; at least part of the second silencing component is arranged on the first silencing component in a sleeving mode, and a second cavity is formed by the second silencing component and at least part of the outer wall face of the first silencing component; wherein at least part of the first silencing part is provided with a plurality of silencing holes, so that the first cavity and the second cavity are communicated through the silencing holes, the silencing frequency band of the first cavity is different from that of the second cavity, the first cavity is communicated with the air outlet of the mounting base, and the second cavity is communicated with the air outlet of the mounting base. At least part of gas flowing out of the mounting foundation flows to the first cavity, the silencing holes and the second cavity for vibration reduction; the problems that in the prior art, compressor micro-perforation can only reduce noise in the same frequency band, and full-frequency-band noise control from low frequency to high frequency cannot be effectively achieved are solved.

The invention provides a video content enhancement method for a low-illumination environment, and the method comprises the steps: achieving the data preprocessing based on an original low-illumination video frame sequence through frame synchronization, color space conversion and local brightness analysis, generating a noise sensitivity thermodynamic diagram through multi-feature unsupervised learning, and constructing a noise perception gating mechanism through the combination of affine transformation. Dynamic modulation of the characteristic channel is realized; in the multi-scale network structure, a channel attention module is used for carrying out layer-by-layer self-adaptive adjustment on a noise sensitive area; a basic illumination image and an edge enhancement image are generated through double-branch decoding, and then weighted fusion is carried out in combination with a noise thermodynamic diagram, so that brightness balance and detail enhancement are realized; a noise smoothing regular term is introduced during end-to-end training, so that the network achieves dynamic balance between an enhancement effect and noise control.

The invention discloses a track noise control method and system based on active acoustic control, and the method comprises the steps: collecting a track noise signal through a sensor array, and processing the signal through Fourier transform to obtain a spectrum distribution characteristic; judging the type of a noise source according to the spectral distribution characteristics, if the spectral distribution shows high-frequency dominance, determining the noise as wheel-rail contact noise, and if the spectral distribution shows low-frequency dominance, determining the noise as rail vibration noise, and obtaining a noise source contribution proportion; according to the noise source contribution proportion, a dynamically adjusted control signal is obtained; acquiring noise source coupling information which changes in real time from the dynamically adjusted control signal, and determining a fused noise source model; according to the fused noise source model, a least square method is adopted to optimize a control strategy, and an optimized control instruction sequence is obtained; and according to the optimized control instruction sequence, acquiring matching data of the current operation density and speed, and if the effect does not reach the standard, iteratively updating the model to obtain final control output.

The invention provides a motor vibration noise control method and system based on modal resonance frequency prediction, and belongs to the field of motor control. The method comprises the following steps: acquiring each order of intrinsic mode frequency of the permanent magnet motor; a cost function parameter, a current constraint condition and a control target are set, and a model prediction control method is adopted to drive an inverter to operate, specifically, the current operation state quantity of the permanent magnet motor is collected; predicting a state response in a future finite time domain based on the operation state quantity; constructing a value function, and evaluating and optimizing a state change result; and selecting an optimal voltage vector, generating a pulse signal to drive an inverter to execute, obtaining a motor high-frequency electromagnetic force wave distribution condition, comparing the motor high-frequency electromagnetic force wave distribution condition with the intrinsic mode frequency of the permanent magnet motor, and optimizing an optimal voltage vector selection logic. The problems that harmonic waves are concentrated and resonance is easily caused by a fixed switching frequency modulation method in the prior art, and a passive suppression method is high in cost and poor in flexibility are solved.

The invention provides an impedance combined type broadband silencer based on a sound wave black hole gradient structure and a design method, and belongs to the technical field of noise control and environmental protection engineering, the whole impedance combined type broadband silencer is of an axisymmetric cylindrical structure, and the impedance combined type broadband silencer is composed of an inlet and outlet channel and a middle-section expanding type acoustic processing area; the expanded acoustic processing area comprises an inlet and outlet side expansion cavity, a composite impedance gradient perforation section and a porous sound absorption material layer. According to the sound wave black hole type multi-stage perforated ring structure, the sound wave black hole type multi-stage perforated ring structure composed of an axial uniform-parameter perforated ring belt and a radial gradient perforated ring belt is sequentially constructed in the silencer, so that the thickness of a perforated ring and the aperture and the perforation rate of the perforated ring belt are arranged on a propagation path according to a parameter gradient rule; porous materials are filled among the annular bands to form a gradient impedance composite dissipation system, so that sound waves are sequentially subjected to focusing and dissipation caused by geometric gradual shrinkage and viscosity and heat dissipation of porous media in the propagation process, and low-frequency enhanced absorption and wide-frequency-band continuous sound absorption are achieved.

The invention discloses a college dormitory noise multi-dimensional evaluation method based on psychoacoustic and sound field simulation, and belongs to the field of building environment and noise control. The objective of the invention is to solve the problem that an existing dormitory noise evaluation method is single in index and neglects subjective perception and spatial distribution heterogeneity. The method comprises the following steps: acquiring physical data and original audio of dormitory noise through multi-point synchronous acquisition; calculating loudness, sharpness, roughness, fluctuation intensity and comprehensive psychoacoustic annoyance (PA) by using a psychoacoustic model, and scientifically quantifying subjective interference of noise; meanwhile, sound field simulation is carried out based on the accurately established three-dimensional dormitory model, a sound pressure level distribution cloud picture is generated, and a standing wave phenomenon and a sound energy accumulation area are visually revealed; and finally, generating a targeted noise reduction optimization strategy by integrating subjective and objective and spatial analysis results. According to the method, full-chain diagnosis of physical characteristics-subjective perception-spatial distribution of dormitory noise is realized, and a scientific basis is provided for accurate and efficient noise treatment.

An electronic device is provided. The electronic device includes a slidable housing including a first housing and a second housing, a first substrate included in the first housing and including a processor, a second substrate included in the second housing, a flexible printed circuit board (FPCB) which includes a ground line, electrically connects the first substrate and the second substrate to each other, and has a shape changed according to the movement of the slidable housing, and a matching circuit electrically connecting the first substrate and at least a portion of the ground line of the FPCB, and changing impedance under the control of the at least one processor according to the shape of the FPCB.

The present application relates to pipeline system damping and noise reduction technical field, provide a kind of active noise cancellation pressure relief valve, comprising: valve body, with the liquid inlet cavity and pressure relief cavity being communicated are formed;Bypass pipe, with liquid inlet cavity is communicated;Piezoelectric actuator and pressure relief component, pressure relief component includes adjusting piece, pressure relief elastic piece and pressure relief valve core, pressure relief valve core and pressure relief elastic piece are set in pressure relief cavity, adjusting piece is movably arranged on valve body, piezoelectric actuator is arranged on adjusting piece, pressure relief elastic piece is pressed between piezoelectric actuator and pressure relief valve core;Piezoelectric actuator is configured to drive pressure relief elastic piece, to eliminate the transient noise caused by pulsating pressure when pressure relief valve core moves.The active noise cancellation pressure relief valve provided by the present application introduces active noise cancellation technology into the active noise cancellation pressure relief valve pulsating noise control by arranging piezoelectric actuator, can be adjusted by pressure relief elastic piece The force exerted on the pressure relief valve core can eliminate the transient noise caused by pulsating pressure when the pressure relief valve core moves.

The invention discloses a voiceprint monitoring method and system integrating bird recognition and noise traceability, and the method comprises the following steps: a position optimization deployment stage: collecting environment parameters of a destination, and carrying out the evaluation of a plurality of candidate positions through a scoring model based on the environment parameters, selecting the candidate position with the highest score as the final deployment position of the microphone array; in the voiceprint data acquisition stage, at the final deployment position, a solar-powered microphone array is used for acquiring mixed sound signals in the environment; a voiceprint analysis processing stage: carrying out parallel processing on the mixed sound signal, the parallel processing process comprising: a bird recognition processing sub-stage: extracting voiceprint features of bird buzzing from the mixed sound signal, and inputting the voiceprint features to a deep learning classification model integrated with a feature enhancement module, and outputting an identification result containing the bird species and the calibrated confidence. According to the invention, high-precision bird monitoring can be realized, and meanwhile, precise noise control can be synchronously carried out based on bird monitoring equipment.

The invention provides a noise isolation type heat energy transfer heating method and system, and belongs to the technical field of industrial waste heat utilization and heating ventilation air conditioning. The system comprises a waste heat fluid collecting unit, a first-stage heat exchanger unit, a middle heat transfer medium circulating unit, a second-stage heat exchanger unit and a heating circulating water conveying unit which are sequentially connected through pipelines. The system further comprises an acoustic isolation structure unit, a temperature regulation and control unit and a system supporting frame unit which are coupled with the thermal unit structure. The core of the system is that through thermal-acoustic integrated collaborative design, waste heat of heat source equipment is efficiently transferred, meanwhile, effective isolation of overall operation noise of the system is achieved through a multi-mode and multi-physical-field noise suppression mechanism, the technical contradiction that heat energy recovery and noise control are separated mutually in the prior art is solved, and the system is suitable for large-scale popularization and application. And the device is particularly suitable for heating places with strict requirements on sound environments.

The invention relates to the technical field of head-up display optimization, in particular to an operation noise control method and device for a vehicle-mounted head-up display, and the method comprises the steps: carrying out the bench noise and vibration testing of a target vehicle-mounted head-up display, so as to collect the body operation noise and vibration data in a bench state; the body operation noise and vibration data in the rack state are compared with a preset threshold value, and under the condition that the body operation noise and vibration data in the rack state are larger than the preset threshold value, motor or vibration isolation optimization is conducted on the target vehicle-mounted head-up display; and under the condition that the body operation noise and the vibration data in the rack state are smaller than a preset threshold value, performing a whole vehicle vibration test on the target vehicle-mounted head-up display to collect vibration data in the whole vehicle state, and optimizing the target vehicle-mounted head-up display according to the vibration data in the whole vehicle state. Therefore, noise generated in the self-checking process of the HUD assembly is effectively reduced, and the sound quality of the whole vehicle is improved.

The invention relates to the technical field of noise control, and discloses a vehicle chassis wind noise optimization method and device, computer equipment, a medium and a product, and the method comprises the steps: carrying out the dynamic mode decomposition of obtained flow field data, obtaining the flow field mode characteristics under different frequencies, screening out the low-frequency mode characteristics of middle and low frequencies, and carrying out the optimization of the low-frequency mode characteristics; therefore, the space-time evolution characteristics of the low and medium frequency wind noise in the vehicle chassis flow field can be accurately analyzed. Furthermore, the flow-induced load characteristic and the sound-induced load characteristic in each low-frequency modal characteristic are decoupled to obtain the sound-induced load characteristic in each low-frequency modal characteristic, so that the influence of airflow fluctuation, structural vibration and the like caused by the flow-induced load on the wind noise analysis is avoided; therefore, the positioning accuracy of the sound source and the propagation path of the wind noise waves is improved. And finally, in combination with the sound source and the propagation path of the wind noise wave, the low and medium frequency wind noise of the vehicle chassis is optimized, and the user experience is improved.

The invention relates to the field of heat management and noise control of ruggedized computers, in particular to a method and a system for self-adaptive noise reduction and regulation of a ruggedized computer. According to the method, temperature, noise and vibration signals are collected synchronously, multi-modal state features are extracted, a fusion feature vector is constructed, and regulation and control parameter suggestions are generated through a neural network model. And further combining with an optimized objective function and a dynamic weight mechanism, iteratively solving optimal regulation and control parameters of fan speed regulation and active noise reduction, generating a fan control and noise reduction control instruction according to a result, constructing an execution structure, and collecting feedback data to realize adaptive updating of the model. Compared with a traditional strategy, collaborative optimization and adaptive adjustment of thermal noise parameters are achieved, and the operation stability and regulation and control intelligence of a ruggedized computer system in a complex environment are improved.

The invention discloses a parameter self-adjusting robust active noise control method, and relates to the technical field of noise control. The method comprises the following steps: acquiring a sound pressure signal in real time, processing the sound pressure signal to form a discrete noise signal as a reference signal, and constructing a dynamically updated reference signal sequence; constructing a filter and generating a weight coefficient thereof, and filtering the reference signal to generate an output signal; processing an output signal of the filter through a secondary path to generate a de-noising signal, collecting a residual signal, feeding back the residual signal to the filter, providing error feedback for self-adaptive iteration of the filter, and driving a weight coefficient of the filter to be optimized and updated; determining an optimal parameter combination for the generalized robust adaptive loss function to realize adaptive optimal determination; and updating a filter weight coefficient vector. According to the method, through organic combination of a self-adaptive parameter adjustment mechanism and a robust control strategy, the fast convergence characteristic, the low steady-state error and the high impact resistance are achieved, and the noise suppression efficiency in the complex environment is remarkably improved.

The invention relates to the technical field of wind power plant optimization, and discloses a wind power plant noise control and power optimization method and device, and the method comprises the steps: obtaining the multi-source noise data of a wind power plant, constructing a multi-source noise feature database, and constructing a noise propagation theoretical model; determining a plurality of monitoring points in the wind power plant based on the noise propagation theoretical model, and collecting actual multi-source noise data and fan operation data of the plurality of monitoring points in real time; on the basis of actual multi-source noise data and fan operation data, a multi-objective optimization function fusing constraint conditions is constructed by taking minimization of dispatching instruction difference, fan operation load and noise superscale as objectives; and solving the multi-objective optimization function to generate an optimal power distribution scheme of the fan under the noise constraint. According to the invention, intelligent monitoring and intelligent control can be carried out on the noise of the wind power plant near the residential area, so that the noise influence of the wind power plant on the nearby residential area is reduced, and the contradiction between the residential area and the wind power plant is solved.

The invention discloses a heat dissipation unit control method and electronic equipment, and relates to the technical field of heat dissipation unit control, and the method comprises the steps: obtaining acoustic signals and vibration signals of a heat dissipation unit in a server in various operation states, and determining a baseline embossing feature and a resonance frequency spectrum of the heat dissipation unit, so as to establish a heat dissipation acoustic archive; acquiring and analyzing a real-time acoustic signal and a real-time vibration signal of the heat dissipation unit to obtain a real-time embossing feature and a real-time frequency spectrum, and judging whether the running state of the heat dissipation unit is abnormal or not; in response to abnormal operation of the heat dissipation unit, judging whether the heat dissipation unit has a resonance risk or not; and in response to existence of the resonance risk, generating a fusion adjustment instruction based on the feature comparison result and the spectrum comparison result. The operation state of the heat dissipation unit can be sensed in real time and pre-controlled, the resonance risk and the abnormal state are avoided, noise is reduced, and the problems that noise control lags behind, depends on hardware structure modification and cannot avoid the resonance risk in advance in the prior art are solved.

The invention relates to the technical field of power management, in particular to an LDO (low dropout regulator) circuit with a wide input voltage range, which comprises a pre-voltage-stabilizing module, a band-gap reference module, an error amplification module, a voltage-stabilizing control module and a power tube, the pre-voltage-stabilizing module is used for preprocessing a wide-range input voltage into a stable low power supply voltage; the band-gap reference module is used for converting the low power supply voltage into a reference voltage; the error amplification module is used for amplifying the difference value between the reference voltage and the feedback voltage of the output circuit into a high-gain and low-noise control signal; the control signal drives the power tube after being compensated and buffered by the voltage stabilization control module, and the power tube converts the wide input voltage into an LDO output signal. Only one LDO main body circuit is adopted, the wide input voltage range can be achieved, high input voltage can be adapted, low input voltage can also be adapted, the use number of components of an LDO chip is reduced, and the occupied area of the chip is greatly reduced.

The invention relates to a multi-channel acoustic black hole sound absorption structure and a silencing device, belongs to the technical field of noise control, and solves the defects of a current acoustic black hole sound absorption structure. The multi-channel acoustic black hole sound absorption structure comprises a shell, one side of the shell is open, and the open side of the shell is used for receiving incident sound waves; partition plates are arranged in the shell to divide the space in the shell into a plurality of sound absorption channels, a plurality of rib plates are arranged in each sound absorption channel, the outer ends of the rib plates are fixed to the inner side face of the shell, the rib plates are arranged perpendicular to the incidence direction of sound waves, the rib plates are arranged at intervals in the incidence direction of the sound waves, and the rib plates are arranged at intervals in the incidence direction of the sound waves. The widths of the multiple rib plates are gradually increased, the inner ends of the multiple rib plates are distributed in a set power law function mode, the inner ends of the multiple rib plates are attached to the outer side face of the perforated plate and fixedly connected with the perforated plate, and the sound absorption structure can better achieve ultra-wideband sound absorption.

The invention discloses a sound insulation and noise reduction water supply and drainage pipeline, and belongs to the technical field of water supply and drainage pipelines, the sound insulation and noise reduction water supply and drainage pipeline comprises a pipeline body and a connecting mechanism, the pipeline body comprises an outer pipe body, an inner pipe body, a supporting ring and a sealing ring, and an exhaust mechanism is arranged at the top of the outer pipe body and comprises an exhaust pipe, a sealing cover and a one-way valve; the two ends of the outer side of the outer pipe body are fixedly sleeved with fixing rings. The connecting mechanism comprises a front connecting base, a rear connecting base, a connecting frame, a fixing frame and a plug pin. The interlayer space between the inner pipe body and the outer pipe body is vacuumized and reliably sealed, the transmission path of sound in the structure is effectively cut off, outward transmission of noise generated by water flow in the pipe and vibration of the pipe is remarkably blocked in the vacuum state, and the overall sound insulation performance is greatly improved; the core measure is supplemented with the design of the supporting ring and the elastic sealing ring, vibration buffering is provided at a key connecting point, energy is absorbed and dissipated, and excellent environmental noise control is comprehensively achieved.

The application provides a kind of multi-channel active noise control method, system, terminal and storage medium, and noise control method includes the following steps: establishing distributed wave domain ANC network model;The global cost function of wave domain ANC problem is split into local cost function and the form of the sum, and a distributed optimization problem is established;Multi-channel distributed wave domain ANC problem is solved using diffusion LMS algorithm, to obtain the estimation of loudspeaker weight;Secondary sound field is generated and residual noise signal is cancelled out.The application also provides a kind of multi-channel active noise control system, terminal and computer readable storage medium.The application uses diffusion strategy to obtain multi-channel distributed wave domain ANC algorithm, so that the calculation burden is dispersed among nodes, compared with centralized scheme, the application makes the expansibility of wave domain ANC system stronger, more robust, more suitable for large-scale application occasions.

The invention discloses a method for evaluating a subjective noise reduction effect of a photovoltaic sound barrier. The method comprises the following steps: measuring, collecting and analyzing a sound sample before noise control; establishing a sound barrier prediction model, and calculating sound barrier insertion loss; synthesizing a noise-controlled sound sample; according to the sound sample before noise control, the sound sample after noise control and the sound barrier prediction model, calculating or measuring to obtain related parameters; and calculating the reduction percentage of the annoyance degree, and evaluating the subjective noise reduction effect of the photovoltaic sound barrier. Through the steps of collecting a sound sample before noise control, establishing a sound barrier prediction model, synthesizing a sound sample after noise control and the like, the annoyance degree reduction percentage calculated based on a sound absorption coefficient and psychoacoustic parameters is obtained, subjective experiments are not needed in the whole evaluation process, time and labor are saved, operation is easy and convenient, and evaluation is rapid and accurate.

The invention relates to a data processing method and device, a storage medium, electronic equipment and a vehicle, and relates to the technical field of data processing.The method comprises the steps that a server side receives an NVH noise level obtaining request sent by the vehicle, and the obtaining request carries the vehicle type, the real-time working condition and driving road information of the vehicle; obtaining a target mapping functional expression in a noise mapping model according to the vehicle type, the real-time working condition and the driving road information; then, the vehicle speed, the vehicle model, the driving road information and the environmental noise serve as input parameters of a target mapping functional expression, and the target NVH noise level corresponding to the environmental noise is calculated through the target mapping functional expression; and the target NVH noise level is sent to the vehicle. According to the technical scheme, the NVH noise level can be obtained through calculation by means of the noise mapping model of the server side, effective NVH information is provided for applications such as intelligent mode planning of the vehicle, effective noise control can be conveniently carried out in real time, and therefore the intelligent control effect of the vehicle is improved.

The present application provides an active noise reduction method and system, a device, a medium, and a vehicle. The method comprises: on the basis of an original noise signal acquired in real time by a noise sensor and an error signal acquired in real time by an error sensor, generating an anti-noise control signal using an improved FxLMS algorithm model, the anti-noise control signal being used for generating anti-noise superimposed on the original noise to suppress the original noise, wherein the improved FxLMS algorithm model comprises an adaptive filter, and the adaptive filter adaptively updates filter coefficients on the basis of environmental parameters generated in real time. In the method, the step size used for adaptively updating the filter coefficients is adjusted using the environmental parameters, thereby improving the iteration speed of the algorithm model, enabling rapid tracking of changes in non-stationary original noise, and achieving effective noise control.

The invention provides a method for testing noise and vibration of a refrigeration fan of a refrigerator, relates to the field of vibration testing of refrigerators, and aims to solve the problem that the real noise performance of the fan in a complex environment in the refrigerator cannot be reflected in the current noise testing of the fan of the air-cooled refrigerator. The actual installation states of a fan, an air duct and a box body are reserved to eliminate single body test deviation, vibration and noise data are synchronously collected, time domain and frequency domain analysis is covered, vibration-noise causal relation tracing is achieved, the coupling frequency band and energy distribution of vibration and noise are quantified through time domain and frequency domain conjoint analysis, and therefore the noise source and the coupling frequency band are positioned, and the noise quality is improved. And targeted optimization is facilitated, and the noise optimization efficiency and the optimized noise control effect are improved.

The invention belongs to the technical field of rubber composite materials, and provides a low-noise rubber track composite material and application thereof. A double-filler synergistic damping design of montmorillonite / silicon carbide composite filler and carbon black grafted with a damping functional polymer is adopted, montmorillonite is loaded on the surface of silicon carbide in an intercalation-stripping composite structure, the stripping degree is 60-90%, the polymer is grafted on the surface of carbon black through a silane coupling agent, the grafting density is 0.3-0.8 chains / nm < 2 >, the mass ratio of the two fillers is 1.5: 1-3: 1, and the damping functional polymer is grafted on the surface of carbon black through a silane coupling agent. And a dual noise reduction mechanism in which rigidity enhancement and viscoelastic damping are cooperated is formed. The loss factor tan delta is larger than or equal to 0.15 in the frequency range of 20-1000 Hz, and compared with a conventional material, the noise is reduced by 10-30 dB. The invention solves the technical problems of poor damping effect and weak noise control capability of the traditional rubber track material, and has wide application value in the fields of engineering machinery tracks, automobile tires, shock absorption and noise reduction materials and the like.

The invention discloses a needle-punched glass fiber aerogel sound-absorbing plate which comprises the following components: 30-50% of a silicon dioxide aerogel precursor, 20-40% of a needle-punched glass fiber felt, 1-3% of a silane coupling agent, 0.5-1% of a dispersing agent, 0.2-0.5% of a defoaming agent, 3-8% of reinforced fibers and 2-5% of a binder. Through needled glass fiber mat reinforcement, silane interface modification and normal-pressure drying processes, collaborative optimization of high strength (compressive strength is greater than 0.64 MPa), high sound absorption performance (sound absorption coefficient is greater than 0.8) and low heat conductivity coefficient (0.018) of the material is realized. The preparation process is simple, the cost is low, and the material is suitable for noise treatment in the fields of buildings, automobiles, aerospace and the like and has remarkable economic benefits and environmental benefits.

Apparatus and methods are described including using a sensor to monitor a sleeping subject and generate a signal in response to the monitoring. A noise control device is controlled in response to the signal.