124 results about "Noise propagation" patented technology

The utility model discloses a mute floor which comprises a surface treatment layer, a protection layer, a decoration layer, a first carrier, a first buffer layer and a second carrier. The surface treatment layer is arranged on one side of the protection layer, the decoration layer is arranged on the other side of the protection layer, the first carrier is arranged between the decoration layer and the first buffer layer, the first buffer layer is arranged between the first carrier and the second carrier, and the first buffer layer is of a porous structure and / or a net structure. A buffer groove is formed in at least one side face of the first buffer layer and extends to the two ends of the side face. By arranging the floor with the first buffer layer with the porous and / or honeycomb structure, noise is reflected and refracted for multiple times in the porous and / or honeycomb structure, so that sound is attenuated, a sound wave propagation path is prolonged, and the effect of more effectively reducing noise propagation is achieved.

The invention relates to a four-body coupling vehicle base vibration noise prediction optimization method and system, and relates to the technical field of rail transit operation and maintenance optimization, and the method comprises the steps: obtaining a vehicle base multi-physics field correlation monitoring data set; carrying out system level assembly in a multi-physics field co-simulation environment to generate a coupled system state parameter matrix; generating sound ray bending trajectory data; loading the vehicle operation condition time sequence data to a wave equation solver, and outputting vibration noise propagation characteristic field distribution data; building a network topology structure to form a prediction model, and executing a back propagation algorithm to train network parameters to a convergence state; designing a vehicle scheduling scheme chromosome coding structure to generate a candidate solution population; and performing selection, crossover and variation genetic operations on the primary solution set, and outputting a vehicle base operation and maintenance scheduling real-time optimization scheme. The method has the beneficial effects that the precision and generalization ability of vibration noise prediction in the future time period are greatly improved, and the fundamental transformation from passive vibration isolation treatment to active prediction optimization is realized.

The invention relates to the technical field of emotion recognition, and discloses an emotion recognition method and system based on visual and auditory synergy, and the method comprises the steps: obtaining an original video stream and an original audio stream, introducing an explicit uncertainty quantification mechanism for a visual mode and an auditory mode, extracting features, and meanwhile, carrying out the recognition of the visual mode and the auditory mode. An uncertainty sequence that assesses its reliability is generated in parallel. Furthermore, the uncertainty sequence is used as a core guiding signal, and a cross-modal cross attention fusion process is dynamically modulated. The mechanism enables the model to adaptively suppress the contribution of an unreliable mode, and focuses on the interaction of high-quality signals, thereby effectively suppressing noise propagation, realizing robust multi-mode information complementation, and finally improving the accuracy of emotion recognition.

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 noise reduction and impact resistance gear structure and a transmission device. The noise reduction and impact resistance gear structure comprises a gear body, a buffering assembly and a noise reduction assembly, wherein the buffering assembly and the noise reduction assembly are arranged in the gear body; the buffering assembly is arranged in the gear body, and the noise reduction assembly comprises sound absorption cotton and is mounted in mounting grooves separated by the fixing frame. The gear box has remarkable noise reduction and impact resistance and can effectively protect gears. And the lubricating device in the gear box can accurately spray oil to provide continuous lubrication for the gear. In the operation process of the gear, the sound absorption cotton can absorb part of sound waves, and noise transmission is remarkably reduced. When the gear is subjected to large impact force, the gear body drives the fixing frame to extrude the telescopic rod, the whole gear body eccentrically moves, and therefore the impact force is dispersed, after the impact force disappears, the movable spring and the sliding spring release energy, the gear body is pushed to recover to the initial state, the service life of the gear is remarkably prolonged, and the operation stability of the gear is remarkably improved.

The invention relates to the technical field of ship navigation observation equipment, in particular to a sonar and noise detection integrated marine ecological monitoring buoy system, which comprises a sonar array dynamic regulation and control module which comprises a sonar array with an adjustable spatial position and dynamically adjusts the dip angle of the sonar array according to the noise propagation direction through a stepping motor driving mechanism, obtaining sonar target data; a noise collaborative sensing module; a sonar-noise closed-loop control module: a noise feature hierarchical extraction unit; a sonar parameter dynamic generation unit; a multi-modal fusion decision unit; the self-adaptive resource scheduling module is used for calculating the effective detection radius of each sonar based on noise energy distribution and dynamically distributing transmitting power; through innovative measures of cooperative work of multiple sonar arrays, noise feature extraction, intelligent resource scheduling and the like, the adaptability and monitoring accuracy of the marine ecological monitoring buoy system in a complex environment are greatly improved, and meanwhile extraction of ecological information and effective suppression of noise are achieved.

The invention relates to the technical field of automobile interior noise control, in particular to an automobile pressure release valve noise control method based on a local resonance acoustic superstructure. The method comprises the steps of obtaining basic data of a target vehicle; carrying out multi-working-condition noise testing based on the basic data of the target vehicle, and determining a main noise frequency; a main radiation source of pressure release valve noise is positioned based on the main noise frequency, and a key path of noise propagation in a vehicle is analyzed; extracting a noise main peak frequency based on the main noise frequency, the main radiation source and the key path, and determining a core noise reduction frequency band; setting a noise reduction target based on the core noise reduction frequency band; constructing a three-dimensional finite element model of the acoustic superstructure based on the basic form of the superstructure; inputting the acoustic superstructure part into the three-dimensional finite element model for simulation analysis; and a simulation analysis result is compared with an initial test result of the target vehicle, a noise reduction effect is analyzed, and the superstructure part is optimized. The sound absorption and insulation structure for specific frequency noise can be designed according to noise sources at the positions of different vehicle types.

The invention relates to an encrypted traffic classification method and system based on semi-supervised contrast learning, and a storage medium, and the method comprises the steps: 1, carrying out the flow division of an original encrypted traffic, respectively aligning the header and load of a data packet in a network flow, and generating an enhanced header and an enhanced load according to an enhancement strategy; step 2, multi-granularity feature extraction: a double-branch feature extractor is adopted to process an enhanced head and an enhanced load respectively, a cross attention mechanism is utilized to obtain fused flow level representation, and depth features are extracted through Mama; and step 3, semi-supervised contrast learning: the contrast learning loss and the cross entropy loss of the label data and the FixMatch loss of the non-label data are integrated, and an encrypted traffic fine-grained classifier is trained. The method has the beneficial effects that the noise propagation is jointly inhibited by comparing the feature structured constraint of learning and a high-confidence threshold filtering mechanism in FixMatch, the training stability is improved, and the labeling cost is remarkably reduced.

The invention discloses a semi-supervised adaptive unstructured scene segmentation method, and relates to the technical field of computer vision. The method comprises the following steps: acquiring label-free image data of an unstructured scene; inputting the weakly enhanced image into a teacher model to generate a first prediction result; inputting the strong enhancement image into the student model to generate a second prediction result; calculating the JS divergence between the first prediction result and the second prediction result, and dynamically adjusting the attenuation coefficient of the index moving average according to the JS divergence; updating teacher model parameters according to the adjusted index moving average attenuation coefficient to obtain an unstructured scene segmentation model; and inputting a to-be-predicted unstructured scene image into the trained unstructured scene segmentation model, and outputting an unstructured scene segmentation result. According to the method, the teacher model weight updating rate is reduced in the model divergence significant stage such as the initial training stage or the difficult sample processing stage so as to suppress noise propagation, and the prediction precision of unstructured scene segmentation is effectively improved.

The application provides a vertical take-off and landing facility unmanned aerial vehicle image site selection method and system facing low-altitude economy, and belongs to the technical field of image data processing and modeling. The method obtains high-overlap-rate images and laser point cloud data by means of oblique photogrammetry and laser radar scanning of a building roof by an unmanned aerial vehicle, constructs a real scene three-dimensional grid model and an obstacle surface three-dimensional model after pretreatment, filters a preliminary layout scheme based on the model according to the available area net height of the roof, carries out airspace safety simulation and noise propagation simulation on each scheme, calculates a minimum interval distance and a noise intensity distribution map, and filters a final site selection scheme according to airspace safety and noise constraints. The application realizes automatic and accurate site selection of the vertical take-off and landing facility in a complex roof environment.

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.

The application provides an exhaust assembly and a food processor. The exhaust assembly comprises a main body and a convex part which can be elastically moved up and down. The main body has an exhaust passage which penetrates up and down. The convex part is arranged on the inner side wall of the main body, extends from one side of the main body to the other side, and has a gap between the other side of the main body. In this way, the convex part blocks the exhaust passage, reduces the area through which the gas in the exhaust passage can flow, and slows down the exhaust speed, thereby reducing noise propagation. Meanwhile, when the gas flow is large, the gas can push the convex part to produce elastic deformation upward, thereby reducing the blocking of the convex part to the exhaust passage and realizing rapid exhaust.

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.

The utility model discloses a transformer cabinet with sound insulation and heat dissipation functions, which relates to the field of transformer cabinets and comprises a cabinet body, a waterproof top is fixedly mounted at the upper end of the cabinet body, a sealing box door is arranged at the front end of the cabinet body, sound insulation plates are fixedly mounted on the inner walls of the cabinet body and the sealing box door, and a heat dissipation mechanism is arranged on the cabinet body. The heat dissipation mechanism comprises external heat exchange fins fixedly installed on the outer side of the cabinet body and internal heat exchange fins fixedly installed on the inner side of the cabinet body, the external heat exchange fins and the internal heat exchange fins are hollow, parallel connectors are fixedly installed at the two ends of the external heat exchange fins and the two ends of the internal heat exchange fins, and a driving mechanism is arranged in the cabinet body. According to the sound insulation and heat dissipation transformer cabinet, the sound insulation plate can convert noise energy into heat energy or energy loss in other forms, so that noise transmission is reduced, and through cooperative use of the heat dissipation mechanism and the driving mechanism, the temperature in the cabinet body can be reduced under the condition that sound insulation is guaranteed.

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.

The invention relates to the technical field of building noise control, and discloses a building noise control method based on sound absorption cavity design, which comprises the following steps: arranging a plurality of sound absorption cavities in a concrete truss, filling a porous sound absorption material in the cavities, covering a micro-perforated plate, and optimizing the noise reduction effect by adjusting the geometric dimensions and the arrangement mode of the cavities. According to the method, the internal space of the concrete truss can be fully utilized, the design parameters are optimized in combination with experimental testing and numerical simulation, low-frequency noise propagation is effectively inhibited, and the additional burden on a building structure is relieved. The sound absorption cavity is formed in the inner space of the concrete truss, and the porous sound absorption material and the micro-perforated plate are combined, so that the inner space of the concrete truss is fully utilized, and the additional burden of a traditional sound insulation measure on a building structure is avoided; the geometric dimension and the arrangement mode of the sound absorption cavities can be flexibly adjusted according to the building floor height and the noise frequency characteristic, and therefore the low-frequency noise suppression capacity is improved.

The utility model relates to the technical field of torque motors, and discloses a high-reliability low-noise torque motor, which comprises a fixed bottom plate, the top of the fixed bottom plate is fixedly connected with a torque motor body, the bottom of the fixed bottom plate is provided with a through groove, and the upper end of the fixed bottom plate is provided with a sound insulation cover. The surface of the sound insulation cover is fixedly connected with an extension plate, and the inner wall of the extension plate is in threaded connection with a threaded rod. The sound insulation cover, the sound absorption cotton and the glass fiber are arranged, specifically, the glass fiber is a high-performance sound insulation material, has good sound absorption and heat insulation performance and can insulate generated noise, and the sound absorption cotton is a porous material and can effectively absorb sound wave energy, reduce noise transmission and further enhance the sound insulation effect. Through double sound insulation of the sound-absorbing cotton and the glass fiber, noise generated during operation of the torque motor body can be effectively absorbed and isolated, noise pollution is reduced, and a quieter working environment is provided.

The utility model discloses a transformer substation prefabricated enclosing wall with a sound insulation function, and aims to solve the problems that a traditional transformer substation enclosing wall lacks a sound insulation function and is affected by noise. The transformer substation prefabricated enclosing wall comprises an enclosing wall assembly and a sound insulation assembly, the enclosing wall assembly comprises a foundation, a first stand column, a top beam and a wallboard, the bottom end of the first stand column is fixedly connected with the foundation, the top end of the first stand column is fixedly connected with the top beam, first mounting grooves are formed in the two sides of the stand column, and the end of the wallboard is arranged in the first mounting grooves; the sound insulation assembly comprises a second stand column and a sound absorption screen, second mounting grooves are formed in the two sides of the second stand column, the end of the sound absorption screen is arranged in the second mounting grooves, and the second stand column is arranged at the top of the top beam and fixedly connected with the first stand column. The sound insulation assembly is arranged at the top of the enclosing wall assembly, the sound insulation height is increased, sound waves can be spread out of the enclosing wall assembly from the top of the sound insulation assembly, the horizontal spreading path is weakened through the sound insulation assembly, and noise spreading in the transformer substation is reduced.

The invention relates to the technical field of sound environment influence prediction, and particularly discloses an AC power transmission line sound environment influence prediction and evaluation method. The method comprises the following steps: determining a plurality of sensitive targets by acquiring project environment data of a target line project; sound source characteristic modeling is carried out on the target line project; planning a plurality of prediction receiving points according to the plurality of sensitive targets, and carrying out noise propagation simulation based on a sound source characteristic model; performing visualization processing on the noise prediction data; comparing and evaluating the noise prediction data; and performing optimization analysis to generate a plurality of engineering optimization suggestions. The method can obtain engineering environment data, determine a plurality of sensitive targets, perform simulation recording of sound source characteristic modeling and noise prediction, fully consider difference of different line structures on noise propagation and actual environmental influence factors according to actual conditions of engineering, determine a plurality of sensitive targets, and perform corresponding planning of prediction receiving points, thereby improving the accuracy of noise prediction. And the prediction precision is effectively improved.

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 invention discloses a collaborative awareness method and system based on multi-scale feature enhancement and region self-adaption, and the method comprises the following steps: firstly, constructing a multi-resolution aerial view feature through a multi-scale channel attention module, and enhancing the channel discrimination ability in combination with a double-flow pooling strategy, thereby cooperatively representing a local geometric structure and global semantic information; on the basis, a two-stage fusion mechanism of regional perception is introduced: in the first stage, global screening and optimization are performed on cooperation features through space-channel attention; and in the second stage, the feature map is divided into a strong perception area and a weak perception area according to the area perception map, differential fusion is implemented, high-confidence features of the vehicle are reserved in the strong perception area, and complementary information provided by a cooperation party is adaptively fused in the weak perception area. According to the method, noise propagation and feature misalignment can be effectively suppressed, and the precision and robustness of three-dimensional target detection in a complex scene are remarkably improved.

The invention belongs to the technical field of recommendation systems, and particularly relates to a recommendation method based on two-channel fusion of graph convolution and hypergraph convolution. According to the method, a two-channel architecture of graph convolution and hypergraph convolution is constructed and is respectively used for capturing explicit interaction information between users and merchants and high-order social information between the users, so that noise interference caused by hyperedge redundancy is effectively relieved; a gating attention fusion mechanism is designed, dynamic aggregation of double-channel embedding is achieved by means of a learnable weight distribution strategy, and recommendation accuracy and personalized expression ability are improved; merchant static features are introduced, category labels, geographical location information and the like are used as semantic vectors to improve recommendation performance, hyperedge noise propagation can be inhibited by means of an information bottleneck principle, and recommendation accuracy is improved.

The present application relates to the technical field of low-voltage switch cabinet, in particular to a low-voltage switch cabinet with sound insulation and noise reduction function; The fixed plate is arranged on the side of the heat dissipation window, the movable plate is arranged on the side, the flexible film is fixed to the upper and lower ends of the fixed plate and the movable plate, the flexible film is connected to the fixed plate and the movable plate, the first recess is formed in the side surface of the fixed plate and the movable plate, the first transmission plate is movably arranged in the inner wall of the first recess, the center shaft and the two side shafts are movably inserted into the side surface of the cover, the transmission belt is movably arranged on the outer surface of the center shaft and the two side shafts, the noise dispersed from the heat dissipation window can only be diffused through the gap between the two movable plates, a plurality of assemblies are arranged in the cover, the noise is propagated in a wave form, the distance of noise propagation out of the main body of the switch cabinet is lengthened, the energy of the noise is greatly consumed, the noise volume dispersed out of the cover is small, and the noise reduction of the low-voltage switch cabinet is realized.

The utility model discloses a sound insulation macromolecule flexible connection structure for a keel, which comprises a mounting shaft, a rolling ring is rotatably arranged on the surface of the mounting shaft, a flexible connection belt is wound on the surface of the rolling ring, the flexible connection belt comprises an anti-tear mesh belt, and shock pads are fixedly arranged on two sides of the anti-tear mesh belt. According to the sound insulation macromolecule flexible connection structure for the keel, the flexible connection structure can be connected with different components in a wall keel structure, transmission of vibration in the structure can be reduced through the arrangement of the two shock pads, and therefore noise is reduced, the sound insulation pad and the sound attenuation pad are arranged in a matched mode, and the sound insulation macromolecule flexible connection structure can play a role in sound attenuation. The noise transmission is avoided, the noise can be really reduced without dead angles, the button is pressed downwards to drive the connecting rod and the cutting blade to move downwards, so that the cutting blade is cut into the flexible connecting belt, and meanwhile, the sliding block is slid leftwards and rightwards, so that the flexible connecting belt can be automatically cut.

The application relates to the field of diesel generating set equipment, in particular to a super-silence diesel generating set which comprises a machine box, air inlets and air outlets are arranged at two ends of the machine box respectively, sound-absorbing assemblies are additionally arranged at the air inlets and the air outlets, the sound-absorbing assemblies are composed of multiple sound-absorbing plates, the multiple sound-absorbing plates are staggered and spaced in a horizontal direction, sound-absorbing channels are formed between two adjacent sound-absorbing plates, the sound-absorbing plates comprise first plate bodies and second plate bodies, the first plate bodies are used for guiding air flow between the inside and the outside of the machine box, and the second plate bodies are used for prolonging noise propagation paths. The application aims to optimize the air inlet pipeline of the generating set without increasing the overall volume of the generating set, to achieve noise reduction treatment, and to consider daily inspection, maintenance or emergency treatment of the generating set.

The invention provides an active noise control system for a vehicle exhaust system and a working method.The active noise control system comprises a control unit, a sound source emitter and an error microphone, the control unit obtains the real-time rotating speed of an engine through a vehicle CAN bus, the sound source emitter is arranged in a pipeline of the exhaust system, and the error microphone is arranged in the pipeline of the exhaust system; the sound source emitter is arranged in the engine and is in communication connection with the control unit, and the sound wave transmission direction of the sound source emitter is opposite to the noise transmission direction of the engine; and the error microphone is arranged in the exhaust pipeline at the downstream of the sound source emitter and is in communication connection with the control unit. The problems that an existing silencer is large in size, and the space and the silencing effect cannot be considered at the same time are solved.

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.

The embodiment of the utility model provides an air scoop, an air supply device and a heat dissipation system, and relates to the technical field of heat dissipation. The air scoop comprises a shell and an air blocking piece, the shell is provided with an air channel, an air inlet and an air outlet, and the air blocking piece is connected with the shell, located in the air channel and used for changing the flowing direction of airflow from the air inlet to the air outlet. The flowing direction of the air flow is changed through the air blocking piece, so that the propagation direction of noise generated by the air flow in the air scoop and noise generated by resistance reduction are changed, and the low-pressure mute effect of the air scoop is achieved.

The utility model relates to the technical field of new energy ships, and particularly discloses a closed cabin structure of a new energy ship. The closed cabin structure comprises a cabin body arranged on the new energy ship; the active noise reduction assembly is arranged on the cabin body; comprising a detection cavity arranged on the inner wall of a cabin body, an audio detection element arranged on one side of the detection cavity, an audio element arranged on one side of the detection cavity and facing the other side of the detection cavity, a circuit board for receiving the audio detection element and controlling the audio element, and a power supply element for supplying power to the audio detection element and the audio element, by adopting the mode of combining active noise reduction and cabin structure passive noise reduction, the noise reduction effect in the cabin is improved on the premise of ensuring various sealing performances of the new energy ship, and the situation that the hearing of sailors is damaged due to the fact that a motor, a generator and the like can generate high noise in the operation process and are exposed in a high-noise environment for a long time is avoided. And noise transmission is effectively reduced, so that sailors can work in a relatively quiet environment.

To provide an electric wire protector which suppresses transmission of noise between one space and the other space separated by an insertion object.SOLUTION: A grommet 1 as an electric wire protector includes a grommet body 10 and a grommet cover 50. The grommet main body 10 includes an inner tube 11 through which the electric wire W is inserted, a flange 12 extending radially outward from a side of the inner tube 11, a base portion 14 connected to the flange 12 so as to include a part of the inner tube 11, and an outer tube 13 connected to an outer peripheral edge of the flange 12 so as to rise on a side opposite to the base portion 14. The grommet cover 50 has an annular top plate 51 having an inner peripheral edge side 51a through which the inner cylinder 11 penetrates, and a cylindrical sidewall 52 covering at least a part of the outer peripheral surface of the outer cylinder 13 and having one end edge continuous with the outer peripheral edge of the annular top plate 51 and the other end edge being an open end.SELECTED DRAWING: Figure 4