1144 results about "Noise control" patented technology

The invention discloses an electromechanical equipment noise reduction method based on machine learning, and relates to the field of electromechanical equipment noise reduction, and the method comprises the steps: collecting sound pressure and vibration signals during the operation of electromechanical equipment, and collecting the operation state data of the electromechanical equipment; sparse reconstruction is carried out on the noise features; carrying out sound source localization on the reconstructed noise features by using a beam forming algorithm to obtain a noise distribution diagram; constructing a noise reduction model based on deep learning to obtain noise signals after noise reduction; extracting the frequency of the noise signal in a preset frequency range through a peak search algorithm; analyzing the acquired running state data by using a time-varying linear predictive coding algorithm TVLPC to obtain a noise frequency offset caused by the abnormal running state of the electromechanical equipment; generating an optimal solution by using a particle swarm algorithm; and according to the optimal solution of noise control, noise dominant frequency components are extracted for separation, and a plurality of phase-reversal noise reduction control signals are obtained. Aiming at low noise reduction precision of electromechanical equipment in the prior art, the noise reduction control precision is improved.

The invention relates to the related technical field of vibration noise control, in particular to an intelligent vibration noise control method and system using frequency spectrum characteristics, and the method comprises the steps: collecting rail transit vibration noise signals, extracting time-frequency domain mixed characteristics, carrying out multi-source separation, generating a noise source contribution degree matrix, configuring a strategy set, and monitoring changes to generate feedback. And the active damper is adjusted in real time for noise reduction. The technical problems that the noise suppression effect is limited and the noise reduction requirement of a complex time-varying scene cannot be accurately matched due to the fact that vibration noise control is difficult to adapt to a dynamically changing vibration noise environment are solved, time-frequency domain mixed features are extracted, overlapped noise sources are identified and separated more accurately, complex characteristics of vibration and noise are comprehensively considered, and the noise reduction effect is improved. And the active damper is dynamically adjusted so as to adapt to changes of vibration and noise, and the accuracy and effectiveness of dynamic adjustment are improved.

A hearing system comprises a hearing device, e.g. a hearing aid or a headset, configured to be worn by a user. The hearing device comprises at least one input transducer for providing at least one electric input signal representative of sound in the environment of the hearing device, wherein said at least one electric input signal comprises a target signal component assumed to be of current interest to the user, and a noise component. The hearing device further comprises a noise control system configured to provide an estimate of said target signal component and an estimate of said noise component and to apply a statistical structure to said noise component to thereby provide a modified noise component comprising said statistical structure; and to determine a modified estimate of said target signal component in dependence of said modified noise component. Thereby an improved segregation of sound sources may be provided.

The invention discloses a foam cement-based sound absorption material with an adjustable and controllable pore structure and a preparation method of the foam cement-based sound absorption material, and belongs to the technical field of building functional materials. Aiming at the problems of insufficient pore structure regulation and control, limited sound absorption performance and high cost of a traditional cement-based sound absorption material, P.O42.5R Portland cement is used as a basis, a physical-chemical synergistic foaming method and a three-stage gradient temperature control freeze-drying process are combined through the synergistic effect of a composite foaming agent, a microporous structure regulator and a composite pore forming agent, and the sound absorption material is prepared. Precise regulation and control of pores from the nm level to the mm level are achieved, and an interconnected pore channel network with the high open porosity is formed. The density of the obtained material is 200-1000 kg / m, the porosity is 60-90%, the aperture coverage range is 2 nm-6 mm, the open porosity is 70-85%, the 28d compressive strength is 1.83-14.56 MPa, the average sound absorption coefficient in the frequency range of 250-2000 Hz is 0.12-0.62, and the noise reduction coefficient is 0.14-0.64. The composite material has the characteristics of adjustable pore structure, light weight, high strength, broadband sound absorption, low cost and good durability, and is suitable for the noise control fields of building walls, traffic facilities and the like.

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 discloses a machine learning optimization method of a low-frequency sound absorption structure based on three-dimensional printing, and belongs to the technical field of artificial intelligence acoustics, the low-frequency sound absorption structure is prepared from a photosensitive resin material through photocuring three-dimensional printing, and comprises a side seam, an extension cavity, a circular through hole, a resonance cavity, a first partition plate, a second partition plate and a third partition plate, the method has good expansibility and can be adjusted according to different noise control requirements; through a machine learning optimization method, structure parameters can be quickly adjusted to cope with a noise control task on the premise of ensuring a small size, so that a remarkable sound absorption effect is obtained at a specific low-frequency band; according to the method, a machine learning method based on a multi-layer perceptron and a genetic algorithm is adopted, geometric parameters of the low-frequency sound absorption structure are optimized, simulation calculation is carried out by using a commercial finite element solver COMSOL Multiphysics, and the sound absorption performance of the structure is further verified and optimized.

The embodiment of the invention discloses a road section noise control method and system of an intelligent guardrail, relates to the technical field of noise control, and is used for solving the problem that the current road section noise control mode is difficult to provide enough noise reduction in real time. The method comprises the following steps: determining noise high-incidence time by acquiring noise detection frequency spectrums of all road sections in a current area; acquiring environmental data by utilizing guardrail detection equipment, and establishing a digital twin model of noise of each road section in combination with a noise detection frequency spectrum; and determining a noise source and characteristics thereof based on the model so as to determine a to-be-adjusted physical structure of the guardrail, and determining adjustment data and a noise reduction value thereof through simulation adjustment. And in combination with the noise reduction value, the noise source and the characteristics, determining the operation parameters of the sound wave offset device to perform active noise reduction, adjusting the guardrail physical structure according to the adjustment data to realize physical noise reduction, and realizing noise control of each road section in the current area.

The invention relates to a cooling noise control method and device for a sand-proof cooling fan in a high-temperature environment. The method comprises the following steps: measuring and analyzing fan blade parameters, a dustproof net cover structure and temperature-dust environment data, and establishing a high-temperature dust coupling dynamic model considering dust adhesion and temperature deformation; performing cyclostationary characteristic decomposition on the fan operation acoustic signal to obtain an environment sensitive Gaussian mixture cyclostationary noise model; calculating a cyclic spectrum correlation function for the fan noise signal and extracting a feature vector to obtain a noise source identification result under a high-temperature sand and dust working condition; and constructing a heat dissipation efficiency function and a noise level function in a temperature-dust-rotating speed three-dimensional parameter space, executing weight adaptive adjustment calculation, and outputting an optimal rotating speed control strategy. Dynamic balance between heat dissipation requirements and noise control is achieved, and the noise level is effectively reduced on the premise that the heat dissipation efficiency is guaranteed.

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 provides a pressure release valve with an active silencing function, which comprises a valve body provided with a liquid inlet cavity and a pressure release cavity which are communicated with each other; the bypass pipe is communicated with the liquid inlet cavity; the pressure relief assembly comprises an adjusting part, a pressure relief elastic part and a pressure relief valve element, the pressure relief valve element and the pressure relief elastic part are arranged in the pressure relief cavity, the adjusting part is movably arranged on the valve body, and the pressure relief elastic part is arranged between the adjusting part and the pressure relief valve element in a pressed mode; the piezoelectric actuator is arranged on the liquid inlet cavity, the noise reduction elastic piece is arranged between the driving end of the piezoelectric actuator and the pressure relief valve element in a pressed mode, and the piezoelectric actuator is configured to drive the noise reduction elastic piece. According to the pressure release valve with the active noise elimination function, an active noise elimination technology is introduced into pulsating noise control of the pressure release valve in the mode of arranging the piezoelectric actuator, and the acting force applied to the pressure release valve element can be adjusted through the noise reduction elastic piece so that transient noise caused by pulsating pressure when the pressure release valve element moves can be eliminated.

The invention relates to the technical field of noise control, and discloses a combined noise reduction and sound absorption unit and a sound absorption board, sound absorption unit structures are periodically arranged and combined to form the sound absorption board with a large area, the sound absorption board is installed on an indoor wall or ceiling of a gas power plant, and indoor low-frequency broadband sound absorption and noise reduction are achieved. The sound absorption device comprises a first sound absorption assembly, the first sound absorption assembly comprises a first shell and a first micro-perforated plate arranged on the first shell, and the first micro-perforated plate is arranged on the first shell; the second sound absorption assembly comprises a second shell, a second micro-perforated plate arranged above the second shell and a second Helmholtz resonant cavity arranged below the first shell; the third sound absorption assembly comprises a third shell, a third micro-perforated plate arranged above the second shell and a plurality of third Helmholtz resonant cavities arranged below the first shell; the first sound absorption assembly, the second sound absorption assembly and the third sound absorption assembly are distributed in parallel.

The invention discloses a reverse design method of an underwater sound absorption superstructure under a multi-material system in the technical field of vibration and noise control. The reverse design method of the underwater sound absorption superstructure under the multi-material system comprises the following steps: predicting the macroscopic sound absorption performance of the superstructure based on an equivalent medium theory; based on an energy homogenization theory of an SIMP interpolation function, establishing a superstructure topological optimization reverse design method under the multi-material system; and a proper material system is selected, and the multi-material superstructure is precisely designed by taking equivalent elastic parameters of the superstructure as targets. Compared with an existing underwater sound absorption superstructure design method, the method has the advantages that large-scale sound-solid coupling finite element calculation can be avoided, and efficient design of the superstructure and good low-frequency broadband sound absorption performance are achieved; in addition, the design method provided by the invention has universality under different multi-material systems.

According to the thin-layer sound absorption superstructure composite acoustic enclosure and the using method, the acoustic enclosure is composed of the cover plate, the conformal frame, the thin-layer sound absorption superstructures and the porous sound absorption materials, the variety of the thin-layer sound absorption superstructures is not limited to one, and the broadband noise reduction effect can be achieved through the parallel superposition design of the thin-layer sound absorption superstructures and the porous sound absorption materials. Wherein the thin-layer sound absorption superstructure can absorb noise in different frequency ranges of medium and low frequency bands, the porous sound absorption material can absorb noise in medium and high frequency bands, and the working bandwidth of the composite acoustic shield after parallel connection and superposition can cover the low, medium and high wide frequency bands. The thin-layer sound absorption superstructure composite acoustic shield further has the advantages of being high in space utilization rate, high in space adaptability, small in thickness, low in surface density and high in material replaceability. Compared with an existing sound insulation cover, on the premise that the thickness is small and the surface density is low, the working frequency band is wider, the sound insulation effect is better, and the sound insulation cover has wide application prospects in noise control of various mechanical and electrical products.

The invention relates to the technical field of active noise reduction, in particular to an in-vehicle noise control method and system, a medium, electronic equipment and a vehicle, and the method comprises the steps: determining a filtering coefficient according to a reference signal collected by a target sensor and an error signal collected by a preset sound collection module on the vehicle; and processing the reference signal according to the filter coefficient to obtain a control signal of the reference signal for noise reduction. According to the method, acceleration sensors at different positions are started or paused according to the driving state of the vehicle, reference signals which contribute to noise greatly are reserved, the noise reduction amount is increased, and input of unnecessary reference signals is reduced.

The invention relates to the technical field of cooling fan control, and discloses an anti-EMI cooling fan filtering and noise suppression system controlled by a dynamic coupling path, and the system comprises a modeling subsystem which is used for carrying out the electromagnetic energy transfer modeling of a cooling fan, and obtaining an EMI energy balance equation set; the extraction subsystem is used for extracting the electromagnetic interference transfer relation among the components of the cooling fan; the calculation subsystem is used for calculating noise energy distribution data in a preset rotating speed range; the analysis subsystem is used for performing frequency self-correlation analysis on the parameter space distribution data to obtain EMI and noise parameter time sequence characteristic data; the real-time adjusting subsystem is used for inputting the EMI and noise parameter time sequence characteristic data into a prediction model for characteristic operation, PWM control correction parameters are obtained, the output power and the rotating speed of a heat dissipation fan are adjusted, and collaborative optimization among EMI suppression, noise control and heat dissipation performance is achieved through the system.

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 belongs to the technical field of converter transformers, and particularly discloses a converter transformer vibration noise control method and system, a terminal and a medium, and the method comprises the steps: constructing a converter transformer structure geometric model, setting material attributes, and carrying out the grid division; based on the geometric model, establishing an electromagnetic field simulation model, applying excitation conditions, obtaining electromagnetic field distribution, establishing an iron core magnetostriction mathematical model, calculating vibration acceleration caused by magnetostriction and transient electromagnetic force of an iron core and a winding, and solving and extracting a displacement field and stress-strain response; establishing an acoustic coupling model on the basis of a structure vibration result, and calculating sound pressure level distribution under different frequencies by setting a structure-air coupling boundary and a matching layer; according to an acoustic simulation result, an iron core positioning structure and an oil tank reinforcing rib arrangement mode are optimized, vibration noise prediction and control of the converter transformer in a multi-harmonic excitation environment are realized, and equipment structure stability, operation reliability and environment adaptability are improved.

The invention relates to the technical field of crushing noise control, in particular to a noise control method, system and equipment for a mobile crushing station and a medium, and the method comprises the steps: obtaining a vibration noise signal of the crushing station, and carrying out the frequency domain conversion of the vibration noise signal to obtain spectrum analysis information; analyzing a frequency band with concentrated noise energy according to the spectrum analysis information to obtain distribution condition information and noise intensity information to generate first reverse sound wave information; historical information of a crushing station is obtained, and a sound wave prediction model is constructed according to the historical information of the crushing station; analyzing the distribution condition information, the noise intensity information and the working point position information according to a sound wave prediction model to obtain second reverse sound wave information; the first reverse sound wave information is adjusted according to the second reverse sound wave information, reverse sound wave output information acting on the loudspeaker is obtained, noise generated in multiple use environments and multiple working conditions of the mobile crushing station can be accurately and rapidly dealt with, and the operation stability of the mobile crushing station is improved.

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 relates to the technical field of vibration and noise reduction of a pipeline system, and provides a pulsating noise active noise elimination pressure release valve which comprises a valve body, a liquid inlet cavity and a pressure release cavity, the bypass pipe is communicated with the liquid inlet cavity; the pressure relief assembly comprises an adjusting part, a pressure relief elastic part and a pressure relief valve element, the pressure relief valve element and the pressure relief elastic part are arranged in the pressure relief cavity, the adjusting part is movably arranged on the valve body, and the pressure relief elastic part is arranged between the adjusting part and the pressure relief valve element in a pressed mode; the electromagnetic actuator is arranged in the liquid inlet cavity, and the noise reduction elastic piece is arranged between the driving end of the electromagnetic actuator and the pressure relief valve element in a pressed mode. According to the pulsating noise active noise elimination pressure release valve, by arranging the electromagnetic actuator, an active noise elimination technology is introduced into pulsating noise control of the pulsating noise active noise elimination pressure release valve, and the acting force applied to the pressure release valve element can be adjusted through the noise reduction elastic piece; therefore, transient noise caused by pulsating pressure when the pressure relief valve element moves is eliminated.

The invention discloses a noise control method and device for a vehicle and the vehicle, and the method comprises the steps: obtaining the parameter value of a target state parameter group of a target vehicle, the target state parameter group comprises a plurality of state parameters, and each state parameter is related to the current noise generated by the vibration of the target vehicle; determining an equipment sound wave signal based on the parameter value of the target state parameter group; and based on the equipment sound wave signal, controlling sound playing equipment of the target vehicle to play sound, so that the current noise sound wave signal interferes with an equipment sound wave signal of the sound playing equipment when being transmitted to a cabin area of the target vehicle, and the noise loudness in the cabin area is smaller than a preset loudness threshold value. According to the invention, the technical problem of large loudness of vehicle noise is solved.

The invention relates to the technical field of noise treatment, and discloses a composite sound absorption and insulation device which comprises a cavity, a Fabry-Perot resonance structure, gradient structure sound absorption felt, two-dimensional dot matrix scatterer sound insulation rubber and a cover plate. An opening is formed in one side of the cavity, and the two-dimensional dot matrix scatterer sound insulation rubber, the gradient structure sound absorption felt, the Fabry-Perot resonance structure and the cover plate are sequentially arranged at the bottom of the cavity in the direction towards the opening. Wherein an opening is formed in the middle of the top of the cover plate; the Fabry-Perot resonance structure comprises a micro-perforated plate and a space coiling channel, and the micro-perforated plate is arranged right above an opening of the space coiling channel and penetrates through the cover plate to be matched with the opening of the cover plate, so that the cover plate covers the rest part of the space coiling channel; through the combination of a plurality of advanced sound absorption and insulation structures, the low-frequency noise of 100Hz and frequency multiplication of the transformer substation is effectively treated.

The invention relates to the technical field of environment noise source type recognition, and particularly discloses an environment noise source type recognition method and device based on a deep convolutional neural network, and the method comprises the steps: collecting environment noise data through a microphone array, carrying out the signal processing of the environment noise data, and generating an environment noise Mel-spectrum image; and performing fine-grained spectral analysis on the Mel-spectrum image of the environmental noise data by using a deep convolutional neural network to capture deep semantic features of the environmental noise, thereby realizing intelligent recognition of the sound source type of the environmental noise data. Through the mode, the method can achieve the quick and accurate recognition of the types of the environmental noise sources, reduces the dependence on the design of artificial features, improves the recognition accuracy and efficiency, and provides powerful technical support for noise control and environmental protection.

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 belongs to the technical field of engines, and discloses a silencing ring gap control method, a supercharger and a vehicle. The noise reduction ring gap control method comprises the steps that a noise reduction ring gap calibration value is obtained based on the current engine working condition; the silencing ring is adjusted, so that the silencing ring gap is equal to the silencing ring gap calibration value; the calibration method of the noise reduction ring gap calibration value comprises the steps that supercharger noise corresponding to different noise reduction ring gaps is tested under the working condition of a to-be-tested engine; and extracting the width value of the silencing ring gap when the noise is minimum under the working condition of the to-be-tested engine, calibrating the width value as the silencing ring gap calibration value under the working condition of the to-be-tested engine, and obtaining the corresponding relationship between the working condition of the engine and the silencing ring gap. According to the noise reduction ring gap control method, accurate control over the noise reduction ring gap can be achieved, the problem of supercharger noise caused by improvement of the engine performance is solved, and effective balance between the engine performance and noise control can be achieved.

The invention belongs to the technical field of air conditioners, and discloses a noise control method and device, an air conditioner and a heat pump. The noise control method is used for noise control in the operation process of the air conditioner and comprises the steps that S1, noise collection and analysis are conducted, specifically, sound quality parameters of noise are collected and analyzed, and the sound quality parameters comprise the loudness L1, the sharpness S1, the roughness R1 and the fluctuation intensity F1; s2, air conditioner operation state parameter collection, wherein the compressor frequency f, the fan rotating speed n and the electronic expansion valve opening degree in the noise state are collected; s3, setting noise reference parameters including loudness Ljz, sharpness Sjz, roughness Rjz and fluctuation intensity Fjz; and S4, noise comparison and air conditioner operation state adjustment are conducted, specifically, the compressor frequency f, the electronic expansion valve opening degree and the fan rotating speed n are adjusted according to the noise comparison result, and the step S1 is executed after adjustment is completed. The noise control method can control the operation state of the air conditioner, so that the operation noise is reduced, the sound quality of a product is improved, and the use comfort of the air conditioner is improved.

The invention relates to a multi-source data fusion-based Ningxia cell noise map construction and evaluation method, which comprises the following steps of: establishing a frequency-variable sound absorption parameter matrix of a building surface based on multi-spectral scanning data and an acoustic database, and combining a burst noise voiceprint recognition result and traffic monitoring data, generating a burst noise influence map through the burst noise space-time correlation model; the real-time sound pressure data and the frequency-variable sound absorption parameter matrix are fused, and a sound field is dynamically reconstructed to generate a noise thermodynamic diagram; and based on a Zwicker loudness model, coupling a burst noise influence map and resident electrocardiogram monitoring data, calculating a composite noise dysphoria index, constructing a noise map in combination with a noise thermodynamic diagram, and carrying out comprehensive evaluation by adopting an entropy weight-TOPSIS algorithm to obtain a noise evaluation result. According to the method, the noise map is constructed through multi-source heterogeneous data fusion, dynamic sound field modeling and physiological and psychological coupling calculation, and evaluation is performed in combination with multi-dimensional indexes, so that precise evaluation of a cell noise environment and scientific dynamic optimization of a noise reduction scheme are realized, and objectivity and pertinence of noise treatment are effectively improved.

The invention relates to the technical field of environmental monitoring and pollution control, in particular to a dust and noise online control system, which comprises a monitoring module, which is used for acquiring data of dust concentration C, particle size D, dust raising position P, noise level N and frequency F through video monitoring equipment and various sensors; the data communication module is responsible for transmitting the data to the central control system; the central control system constructs a fuzzy control rule base according to the dust-related data, adjusts parameters of dust removal equipment in combination with a PID algorithm, and controls noise reduction equipment by adopting an adaptive filtering algorithm according to noise data; the risk assessment and early warning optimization module uses a risk assessment model to calculate a risk grade R and performs graded early warning; the governance execution module comprises a dust hood, a sprayer and noise reduction equipment and carries out dust and noise governance according to an alarm, and the air volume regulation module regulates the air volume of a dust suction port through a neural network algorithm by means of feedback of a sensor on a regulation valve; the invention aims to solve the problems of effective monitoring, precise treatment and scientific early warning of dust and noise.

The invention provides a variable blade type noise control system which comprises a shape memory alloy fan blade, a distance high-frequency heating device and a controller, and the shape memory alloy fan blade is arranged on a fan disc and supported by a low-pressure shaft; the distance high-frequency heating equipment is used for providing distance high-frequency heating for the low-pressure shaft; the controller is used for recognizing the flight stages of the aero-engine and is in signal connection with the air high-frequency heating equipment so as to provide different heating instructions for the air high-frequency heating equipment according to different flight stages, and then the shape memory alloy fan blades are heated to change the blade types by means of the memory characteristics. The invention further provides a variable blade noise control method. The system and the method can give consideration to the working efficiency of the blade and noise control in different flight stages.