29 results about "Noise propagation" patented technology

This utility model provides an air inlet grille and a range hood including the same. The air inlet grille is installed at the air inlet of the range hood and includes several layers of spaced-apart air inlet plates. Multiple air inlet holes penetrating all the air inlet plates are formed on the air inlet grille. This air inlet grille and the range hood including the same form a multi-layer grille structure through the layers of spaced-apart air inlet plates and the air inlet holes penetrating all the air inlet plates. This allows the sound waves generated by the range hood to be reflected and scattered multiple times by the multi-layer grille when passing through the air inlet holes, gradually weakening the sound wave energy, reducing noise propagation, thereby improving sound insulation and enhancing the user experience.

This application discloses a novel noise reduction structure for a pressure cooker, comprising: a noise reduction seat with openings at both the top and bottom, and a noise reduction cover that can be opened and closed and is disposed above the noise reduction seat. The noise reduction seat and the noise reduction cover are fitted together to form a receiving cavity covering the pressure vent cap. The noise reduction cover has a vent hole, and the inner sidewall of the noise reduction cover protrudes towards the receiving cavity corresponding to the position of the vent cap, forming a reflux wall. This embodiment, through the enveloping receiving cavity formed by the noise reduction seat and the noise reduction cover, completely covers the pressure vent cap within a closed space, forming a physical barrier layer to directly weaken noise propagation. Simultaneously, the reflux wall forces steam to swirl downwards, reducing steam velocity and impact energy before it is discharged outwards through the vent hole. This dual effect attenuates high-frequency impact noise by over 40%, and the compact integrated structure avoids the volume defects of traditional screw-on devices.

This invention provides a vibration-damping and noise-reducing track structure for RGV (Remotely Resistant Vehicle). The RGV vibration-damping and noise-reducing track structure includes: a vibration-damping base; two tracks, which are mounted on top of the vibration-damping base via multiple sets of fixing brackets. Each set of fixing brackets has fixing bolts installed on its top. The vibration-damping base includes a support structure, a vibration-damping structure, and a wear-resistant structure. The wear-resistant structure is installed between the support structure and the wear-resistant structure, and the vibration-damping structure is a rubber damping pad; filling openings are located at both ends of the tracks, and the interior of the filling openings is filled with a filling structure, which is made of foam plastic. Each track has a sliding opening on its top. The vibration-damping and noise-reducing track structure for RGV provided by this invention can effectively isolate vibration transmission between the track and the foundation, reducing ground vibration and noise propagation, reducing ground vibration amplitude by 30%-40%. Simultaneously, the filling structure can absorb noise, improving the noise reduction effect.

This invention relates to the field of bearings, specifically to a noise-reducing bearing with an integrated micro-perforated plate sound-absorbing structure. Rolling elements are disposed between the inner and outer rings of the bearing, and these rolling elements are positioned at intervals by a cage. A sealing ring is disposed on one side of the outer ring. The sealing ring has a mounting structure for installing the micro-perforated plate. The micro-perforated plate is annular and installed at the sealing ring, with a uniform array of micropores. An air cavity is formed between the micro-perforated plate and the sealing ring, constituting the back cavity of the sound-absorbing structure. In this invention, by setting a micro-perforated plate sound-absorbing structure at the bearing's sealing structure, the bearing maintains its original sealing function while possessing active sound absorption capability. When noise generated during bearing operation propagates to the micro-perforated plate, sound waves enter the micropores, generating viscous friction and heat exchange between the air and the pore walls within the micropore channels, thereby converting some of the sound energy into heat energy and dissipating it.

The utility model relates to electric motor car technical field discloses a kind of electric motor car motor of middle placement, including protective shell, the inner bottom wall of protective shell is fixedly connected with backing plate, the utility model passes through polyurethane elastomer backing plate, absorbs the vibration energy generated when motor runs, play buffering effect, to reduce the amplitude of vibration transmission to external structure, effectively reduce the noise caused by vibration, simultaneously, sound insulation and noise reduction board of protective shell both sides, its internal fiber structure can produce multiple reflection and absorption to sound, further reduce noise propagation, the aperture of conical sound insulation hole on the surface of sound insulation and noise reduction board gradually decreases, so that sound is hindered and reflected by different aperture size when passing, effectively reduce the propagation intensity of sound, reach better sound insulation and noise reduction effect, significantly reduce the noise when electric motor car motor runs, avoid the adverse effects of traditional motor noise on riding comfort and surrounding living environment.

An apparatus and method for diagnosing a microphone of a vehicle reduce an interior noise by applying an active road surface noise reduction method, learn sounds collected using a plurality of microphones to generate a simulated signal for a specific microphone, and detect a failure of the specific microphone by comparing the simulated signal with an actually measured sound of the specific microphone so that noise reduction efficiency can be improved by distinguishing a noise from an interior sound, a failed microphone can be accurately detected using the sounds of the plurality of microphones, the spread of an unnecessary noise can be prevented by diagnosing a failure of the specific microphone, and a more comfortable and stable interior environment can be provided to occupants.

The utility model discloses an underground space sound absorption ceiling structure unit and ceiling system, including arc's frame structure, a plurality of square keel frame, a plurality of hanger muscle parts and a plurality of decorative board, arc's frame structure is fixed on the top wall body of chamber, and at least one sound absorption component I is installed in the frame structure, a plurality of square keel frame is arranged along the chamber width direction and is parallelly arranged, and the height of every column keel frame is not exactly the same, is used for dispersing sound wave, one end of hanger muscle part is connected with keel frame, and the other end is connected with frame structure, is used for suspending the keel frame in chamber top, and the decorative board is installed on the keel frame, and at least one sound absorption component II is installed between decorative board and keel frame. The utility model has good sound absorption, can be good at insulating noise propagation, and improves the inside sound control effect.

A frequency shifting device based on the Doppler effect, a noise bypass frequency shifting device based on the receiver, a composite noise reduction device, and a method are disclosed. The frequency shifting device based on the Doppler effect includes: a rotor module (101) with a noise port, the noise port including a first noise port (10101) and a second noise port (10102). The first noise port (10101) is connected to the second noise port (10102) on the noise propagation path. The first noise port (10101) is used to connect to a sound source or output frequency-shifted noise. The second noise port (10102) follows the rotor module (101) in a periodic motion relative to a reference frame, causing a Doppler effect due to the relative motion between the second noise port (10102) and the noise source. This results in a frequency shift in the transmission or reception frequency relative to the reference frame. The frequency shift of the second noise port (10102) relative to the reference frame is controlled by changing the speed of the periodic motion. The reference frame includes an inertial reference frame and a non-inertial reference frame. This invention addresses the technical deficiency of existing general-purpose silencer technology, which suffers from the invariability of silencing characteristics due to limitations in material properties or structural design. It realizes a new type of silencer with variable silencing characteristics, namely, a frequency shifting device, silencing equipment, and method based on the Doppler effect.

The application provides a measurement preprocessing method based on correlation entropy and attention mechanism. The dynamic weight is calculated through the Gaussian kernel correlation entropy of the historical innovation and the current innovation in the sliding window, and the abnormal measurement is adaptively identified and suppressed. The method adopts a feedforward inhibition mechanism to block noise propagation, while retaining the optimality of the KF framework, and realizes efficient anomaly detection with lower complexity. Simulation experiments show that in the Gaussian mixed noise and impulse noise scene, the application significantly reduces the mean square error of KF, the dynamic window mechanism is faster than the noise statistical modeling algorithm in response speed, the tracking accuracy is equivalent to Huber-KF, and the parameter adaptability is stronger, which verifies the robustness and tracking performance of the method in non-Gaussian noise, especially in the impulse noise environment, and provides theoretical support for subsequent expansion to the maneuvering target scene and deep learning fusion.

An electronic device (10) comprising: a housing (11); a circuit board (12) arranged within the housing (11) on which a plurality of circuit elements are mounted; and a shielding housing (15) provided on the circuit board (12) and made of metal. Among the plurality of circuit elements, a circuit element requiring electromagnetic shielding is located in a region of the circuit board (12) where the shielding housing (15) is provided. For example, the electronic device (10) further comprises a plurality of shielding clips (16) that electrically connect the shielding housing (15) to a ground pattern of the circuit board (12). The intervals of the plurality of shielding clips (16) are configured based on a noise propagation characteristic in a vacuum.

The utility model provides air conditioner fan low noise deep groove ball bearing relates to bearing technical field, include: outer shaft ring and sealed noise reduction structure, the inside of outer shaft ring is equipped with inner shaft, is equipped with ball between inner shaft and outer shaft ring, the outside of outer shaft ring and inner shaft is equipped with sealed noise reduction structure, sealed noise reduction structure contains following subassembly: sound absorbing ring: pastes in the outside of outer shaft ring, and the both ends of sound absorbing ring are equipped with thread ring groove, through setting sealed noise reduction structure, through pasting sound absorbing material in the outside of bearing, can high -efficiently absorb the mechanical vibration and noise energy of bearing operation, reduce the noise propagation intensity, effectively improve the noise problem of air conditioner fan operation, set up the sealing ring between outer shaft and inner shaft can effectively block the invasion of outside dust, fiber and other impurities, avoid dust impurity aggravating the abrasion of ball and raceway, eliminate the noise hidden danger caused by ball movement instability, thereby all -round promotion bearing's noise reduction performance and operation stability.

The utility model relates to a transformer of noise suppression. The technical problem that the utility model wants to solve is to provide a transformer of noise suppression. The utility model adopts the technical scheme: including transformer core, transformer coil, upper clamping beam, the copper plate is equipped with the transformer coil lead-out end, the upper clamping beam is installed and is butt -joint support assembly, the copper plate with butt -joint support assembly is connected fixed through insulator subassembly between, the upper support includes upper support butt -joint part, is equipped with upper support positioning slot on upper support butt -joint part, the upper clamping beam is the mouth character shape structure, and it includes upper clamping beam inside part, upper clamping beam outside part and upper clamping beam upper part. The utility model has the advantages of: setting the slow vibration pad at the upper support installation place, setting the noise reduction spring at the both ends of insulator and externalizing the noise reduction sleeve, so that the upper clamping beam and the copper plate connection place between all adopt the elastic connection transition and have the buffer vibration effect, effectively suppress the vibration noise spread.

The utility model discloses a kind of noise reduction mechanism for switch board, it is related to switch board technical field, including cabinet, the inside side wall of cabinet is fixed with sound insulation board, first sound absorption hole is equidistantly arranged on sound insulation board, the inboard of each first sound absorption hole is provided with sound absorption pipe, second sound absorption hole of even distribution is provided on each sound absorption pipe, heat dissipation hole is provided in the bottom of cabinet side, heat dissipation hole is communicated with the first sound absorption hole of sound insulation board one side bottom, the top of cabinet is fixed with cooling mechanism, the bottom end inner wall of cabinet four corners is fixed with first rubber pad, the upper end of four first rubber pads is fixed with U type frame. In the utility model, noise is absorbed by sound insulation board, sound absorption hole and sound absorption pipe, and noise propagation is reduced;Utilize rubber pad and elastic component to reduce element vibration and noise transmission;Fan in cooling mechanism cooperates with dust filter screen, can both cooling and dust prevention, ensure normal operation of equipment, simultaneously, heat dissipation hole is combined with sound absorption structure, give consideration to heat dissipation and noise reduction.

The application relates to the technical field of sand making machines, in particular to a high-efficiency low-noise sand making machine and a use method thereof, which comprises a box body, the surface of the box body is provided with a sound absorption assembly. The application has the advantages of noise reduction and multiple crushing modes. In the actual use process, the introduction of the noise reduction design greatly improves the noise reduction performance. The metal fiber layer one is combined with the nano sound absorption layer one and the nano sound absorption layer two to form a high-efficiency sound absorption structure, sound wave energy is effectively absorbed, the perforated aluminum plate and the graphene foam sound absorption layer further reduce noise, the pleated wall sandwich barrier significantly consumes sound wave energy through multiple reflection and scattering, and finally, the stainless steel skin effectively blocks external noise. This design significantly reduces noise propagation and reflection, provides excellent sound insulation effect for the box body, effectively reduces the noise level, and creates a more quiet and peaceful working environment for the operators.

This utility model provides a reversing valve with noise reduction function, relating to the field of reversing valve technology. It includes a reversing valve body with a trapezoidal cavity inside and near the top. A feed pipe is fixedly connected to the top of the reversing valve body, communicating with the trapezoidal cavity. Symmetrically arranged circular cavities are also inside the reversing valve body near the bottom, with connecting holes connecting the trapezoidal and circular cavities. A water outlet is provided at the bottom of each circular cavity. A circular hole is also provided inside the reversing valve body at the circular cavity. In this utility model, through the synergistic effect of "fluid flow stabilization design (trapezoidal cavity, cone head, and fixed sleeve combination, plus mechanical vibration buffering (spring and convex rod structure), and noise propagation isolation (sound insulation cylinder)," it can effectively reduce fluid impact noise and mechanical vibration noise, thereby improving the production environment and meeting the needs of precision equipment, quiet workshops, and other scenarios.

The application discloses a layered composite sound insulation material based on noise propagation path blocking and application, and belongs to the technical field of automobile NVH noise reduction. The layered composite sound insulation material comprises, from top to bottom, a damping layer, a sound absorption layer, a sound elimination layer, a barrier layer and a buffer layer. The sound absorption layer is provided with a plurality of holes. The sound elimination layer is provided with a honeycomb structure, and the honeycomb structure is filled with paraffin microcapsules. The material realizes synchronous noise reduction of medium-high frequency noise and low frequency noise through the cooperation of the five-layer structure, and the material has good toughness and softness, and has high adhesion with automobile parts, so that the noise reduction and sound insulation effect can be further improved.

The utility model relates to the technical field of gas turbine power generation, in particular to gas turbine combined cycle power generation low-noise emission equipment which comprises a sound absorption box body, a box door is hinged to one side of the sound absorption box body, and through holes are formed in the two faces of the sound absorption box body respectively. The silencing box body is arranged in the sound absorption box body, an air inlet is formed in one side of the silencing box body, an air outlet is formed in the other side of the silencing box body, and the air inlet and the air outlet are matched with the through holes in the two faces of the sound absorption box body respectively. Compared with the prior art, by arranging the silencing box body, the multistage serially-connected silencing cavities and the complex airflow path, stage-by-stage attenuation, disturbance and dissipation of sound waves are effectively achieved, linear propagation and high-frequency impact of noise are avoided, the noise reduction efficiency is improved, and the noise pollution risk of the system is reduced.

This invention discloses an adaptive optics modal gain scheduling method for space-to-ground laser communication, belonging to the fields of space-to-ground laser communication, free-space optical communication, adaptive optics control, and optical communication link state awareness. The method constructs a training state sample set based on offline profile-link state sample data and represents the state samples as profile-link state vectors. It generates offline modal optimal gain labels through a modal group residual phase variance model composed of fitting residuals, servo hysteresis residuals, and noise propagation residuals. It constructs and trains a physical supervision proxy model. At the current scheduling moment, it acquires the real-time profile-link state vector, forming a slow modal gain scheduling result containing low-order, mid-order, and high-order modal control gains. This invention can reduce modal mismatch caused by uniform scalar gain and improve the optical compensation quality of space-to-ground laser communication links.

This invention belongs to the field of indoor positioning technology and discloses a robust indoor positioning method and system based on the weighted LP norm. The method first constructs a linearized measurement model based on TOA ranging values; then, it constructs an outer weight matrix by calculating the covariance of noise propagation error, and combines this with an inner weight matrix constructed from the current residuals to form a weighted LP norm objective function; an iterative optimization algorithm is used to solve this objective function until convergence yields the final coordinates of the user device. This invention adaptively suppresses the influence of impulse noise and outliers through a two-layer weighting mechanism, maintaining high positioning accuracy and stability even in non-Gaussian noise environments. This method requires no additional hardware, has high computational efficiency, and is easy to deploy in engineering. It is not only applicable to UWB systems but can also be extended to other ranging-based wireless positioning scenarios.

This invention relates to the field of noise environmental impact assessment technology, and discloses a method and related apparatus for assessing the noise environmental impact of onshore wind farms. The method first constructs a discretized representation containing spatial coordinates, calculates noise propagation attenuation and directional parameters, and establishes a propagation path feature association array; it then matches the wind turbine sound power level with hourly meteorological data of the assessment benchmark year, determines the directivity correction amount, and forms a complete propagation array containing time-varying sound source parameters; it calculates and superimposes the hourly noise contribution value of each wind turbine, obtains the daily continuous equivalent sound level through energy averaging, and extracts the maximum continuous equivalent sound level as an evaluation index; based on the index, it generates a spatial distribution report of noise impact. This invention constructs a dynamic sound source intensity model, uses a gridded array algorithm to improve computational efficiency, comprehensively considers multiple attenuation mechanisms and the superposition effect of multiple wind turbines, accurately reflects the actual operating conditions of the wind farm, and significantly improves the accuracy and scientific nature of the noise assessment results.

This invention relates to the field of electromagnetic compatibility technology, and particularly to a method, device, electronic device, and storage medium for predicting far-field radiation from a communication power supply. The method includes: analyzing the common-mode noise propagation path of the communication power supply and establishing a dual-excitation-source radiation model containing both input port and output port common-mode excitation sources. This application achieves separate analysis of the radiation contributions from the input and output ports by establishing a dual-excitation-source radiation model; improves the accuracy of key parameters by obtaining the impedance parameters of each port separately and accurately converting the excitation source voltage using a sampling measurement circuit; further, it obtains the maximum radiation transfer function through full-angle simulation to ensure prediction coverage of the worst-case scenario; finally, it calculates the total radiation prediction value by integrating the above parameters, thus forming a complete and reliable prediction process that significantly improves the accuracy and practicality of far-field radiation prediction.

The application provides a subway station multi-modal data noise processing method, computer equipment and program product, which is applied to a subway station multi-source perception data processing scene, and is used for realizing noise identification and abnormality repair in a multi-modal data fusion process. First, each modal data from different devices is subjected to space-time alignment processing, multi-source data is uniformly mapped to a same time slice and a station space unit to obtain corresponding multi-modal data, on the basis of which, a dynamic fusion feature of a current time slice is constructed for each station space unit, noise embedded in the dynamic fusion feature is identified based on cross-modal consistency features in the dynamic fusion feature and modal data feature representations, an abnormal modal is located, finally, target modal data feature representations corresponding to the abnormal modal are repaired, and the repair result is written back to the dynamic fusion feature for updating, so as to suppress noise propagation and improve the accuracy of the fusion result.

The application discloses a feature extraction method and system integrating source end purification and end alignment of a residual network, and the method comprises the following steps: obtaining a first layer feature map after convolution and normalization of an input image, applying a channel attention mechanism and a spatial gating mechanism to generate a joint mask, completing first layer feature purification and exporting cross-layer carrying representation; inputting the purified feature map into a residual network trunk to perform layer-by-layer convolution transformation and residual superposition to obtain a deep layer feature map; performing upsampling, channel attention screening and 1*1 convolution channel mapping on the cross-layer carrying representation to obtain an alignment feature map; element-by-element adding and fusing the alignment feature map and the deep layer feature map, performing batch normalization, nonlinear activation, global average pooling and full connection layer processing to output a classification result. The application inhibits noise propagation to a deep layer through source end purification, realizes effective complementation of shallow positioning information and deep layer semantics through end alignment, has small parameter overhead and is easy to embed into an existing residual network architecture.

The application provides a small rail transit train noise prediction method and system, and relates to the technical field of rail transit, comprising the following steps: constructing a speed correction model according to the positional relationship among a prediction point, a measurement point and a track surface; constructing a geometric divergence correction model according to train speed; constructing an air absorption attenuation model according to a pure tone attenuation coefficient and the position of the measurement point; constructing a ground effect attenuation model according to the average ground clearance of the propagation path and the position of the measurement point; constructing a line type correction model according to track information; calculating the single-event sound level of a single train passing through the prediction point according to the maximum noise source intensity, the speed correction model, the geometric divergence correction model, the air absorption attenuation model, the ground effect attenuation model and the line type correction model; and calculating the equivalent continuous sound level according to the time of the single train passing, the single-event sound level and the train logarithm. The application decomposes the noise propagation process into quantifiable physical links for correction, and outputs the equivalent sound level index meeting the engineering application requirements.

The application discloses an improved ranging method based on unmanned aerial vehicle rotor noise directivity modeling, comprising arranging a multi-channel acoustic sensor array, collecting noise signals from rotors in real time during unmanned aerial vehicle flight; filtering, time synchronizing and normalizing the collected original noise signals for pretreatment; performing time domain analysis and frequency domain analysis on the pretreated acoustic wave signals; establishing an unmanned aerial vehicle rotor noise directivity model, performing spectrum analysis and spectrum feature extraction; establishing a multi-path model of noise propagation, performing signal demixing and correction, and simultaneously dynamically compensating the unmanned aerial vehicle rotor noise directivity model according to environmental factors; combining time delay, intensity difference and spectrum change information received by the multi-channel microphone array, calculating the relative distance between the unmanned aerial vehicle and the target by using a geometric positioning algorithm, and establishing a joint model to optimize ranging accuracy; and the application effectively improves the accuracy and reliability of unmanned aerial vehicle ranging and reduces traditional errors.

The application relates to the technical field of natural language query, and discloses an intelligent question and answer system supporting structured and text data composite query. The natural language interaction module receives a natural language query request of a user, the query intention analysis and routing module identifies the intention of the natural language query request, and according to the identification result, the natural language query request is adaptively routed among a structured data query link, an unstructured document retrieval link and a fusion query link, and the query results of different links are obtained through the structured data query module, the unstructured document retrieval module and the result fusion and output module respectively. The application significantly reduces the information omission risk caused by simplifying the fusion type problem into pure database query, avoids the noise propagation and non-evidence completion in the document question and answer, and improves the verifiability and explainability of the answer.

A cooling tower noise reduction sound insulation barrier, including four identical structure sound insulation unit, sound insulation unit includes a pair of stand, the lower end of the stand is provided with a connector, the lower end of the connector is welded with a mounting plate, the mounting plate is installed on the foundation by bolts, the stand is provided with a plurality of rectangular tubes, the rectangular tube is provided with a wall plate through the screw, the stand and the connector between this kind of convenient disassembly and installation. The front side of the wall plate is provided with a plurality of sound attenuation members, the two ends of the adjacent two sound attenuation members are respectively provided with a concave member, the outer side end of the concave member is bent outward to limit the convex part, the inner wall of the limiting convex part acts on the outer wall of the sound attenuation member, and the concave member is installed on the stand by screws. Through the setting of sound attenuation member and wall plate double effect further weaken the energy of noise propagation, so as to play the purpose of noise reduction. And through the setting of concave member, the fixation of sound attenuation member is convenient, and the stability after fixation is strong.

The application relates to the technical field of horizontal milling machines, in particular to a sound insulation and noise reduction device for a horizontal milling machine spindle box, which comprises a mounting base, a mounting frame, a supporting sliding frame, a mineral fiber plate, sound absorption holes, a fixed plate and a pull plate; the mounting base is provided with the mounting frame for placing the milling machine spindle box at the upper end center, the supporting sliding frame is mounted around the front end of the mounting frame, the mineral fiber plate for converting sound energy into heat energy to absorb sound is slidably connected in the supporting sliding frame, a plurality of sound absorption holes for absorbing medium and high frequency noise by utilizing micro pores are linearly arranged on the surface of the mineral fiber plate, sound energy is converted into heat energy to absorb sound by the mineral fiber plate, medium and high frequency noise is absorbed by the sound absorption holes, the noise generated during the operation of the milling machine is effectively reduced, the stability and impact resistance of the equipment are enhanced through the joint action of the damping assembly, and the noise propagation caused by vibration is reduced.

This invention discloses a wavefront tomography reconstruction optimization method for non-pupil plane position aberration detection, belonging to the field of adaptive optics technology. The method first establishes a relationship matrix including the ground layer and the non-pupil plane upper-air layer based on multi-beacon configuration and the hierarchical representation of atmospheric turbulence by height. Then, it constructs system response matrices at different reconstruction orders and solves the corresponding wavefront reconstruction matrices using the least squares method. Furthermore, considering the influence of higher-order unmodeled modes on the measurement signal, it calculates the wavefront fitting error, noise propagation error, and mode aliasing error at each order. Finally, based on the relationship between the total residual error of the system and the reconstruction order, it determines the optimal reconstruction order that minimizes the total error and constructs the final wavefront reconstruction matrix based on this order. This invention reduces the influence of mode truncation and aliasing errors, improving the accuracy and stability of non-pupil plane aberration detection.