48results about How to "Meet the needs of noise reduction" patented technology

The invention discloses an adaptive ear canal active noise reduction earphone and an adaptive ear canal active noise reduction method. The earphone comprises a loudspeaker, an audio input module, a microphone, an operation module and a noise reduction processing module, the audio input module, the operation module, the microphone and the loudspeaker are all connected with the noise reduction processing module, and the microphone is arranged in a front cavity of the loudspeaker. The noise reduction method comprises the following steps that 1, an artificial ear acquires calibrated audios to obtain a third frequency response curve and a third phase curve; 2, the microphone acquires the calibrated audios and surrounding sounds simultaneously to obtain a first frequency response curve, a firstphase curve and a second phase curve; 3, the operation module conducts operation according to data obtained in the step 1 and the step 2 and a fixed algorithm to obtain a filter coefficient; and 4, the noise reduction processing module conducts noise reduction processing on the audios by using the filter coefficient. The earphone and the noise reduction method can adapt to the noise reduction requirements of various different ear canals, meet the noise reduction requirement of users and provide a good experience feeling for the users.

Embodiments of the invention disclose a denoising method and device for a photographed image.The method comprises the following steps: determining a corresponding denoising coefficient according to a current sensitivity value; denoising the photographed image according to the denoising coefficient; and outputting the denoised photographed image. According to the denoising method and device in the technical scheme provided by the embodiments of the invention, the technical problem in the prior art than when a photographing environment is relatively bright, a relatively large denoising coefficient adopted in the prior art is stilled used for denoising to cause a fuzzy image, higher definition of the photographed image is guaranteed, the existing denoising technology of the photographed image is optimized, and the increasing individual and convenient denoising demands of people on the photographed image are satisfied.

The invention discloses a prefabricated track plate structure capable of absorbing wheel track noise. The prefabricated track plate structure comprises a prefabricated plate. Steel tracks are arranged on the upper surface of the prefabricated plate. The prefabricated plate is integrally arranged in a groove of a base platform. An anti-vibration pad is arranged between the prefabricated plate and the groove of the base platform. A noise absorbing plate is further arranged in the position, between the steel tracks, of the upper surface of the prefabricated plate. The noise absorbing plate is made of porous spherical particles. The two sides of a base body are provided with retaining walls. Thus, the prefabricated track plate structure capable of absorbing the wheel track noise is simple in structure, the vibration damping requirement and the noise reduction requirement are both met, the demand for the strength is also met, and meanwhile the firefighting evacuating function is achieved.

The invention discloses a sound absorption and insulation composite member and a transformer. The sound absorption and insulation composite member includes a constrained damping sound insulation assembly and an impedance composite sound absorption assembly, wherein the constrained damping sound insulation assembly includes a rigid base layer, an elastic damping layer and a rigid constraining layerwhich are sequentially stacked, the impedance composite sound absorption assembly is stacked on the rigid base layer and includes a porous sound absorption unit and a resonance sound absorption unitwhich are sequentially stacked, and the resonance sound absorption unit includes a micro-perforated plate and a first cavity. The sound absorption and insulation composite member is advantaged in thatthe constrained damping sound insulation assembly is set, the elastic damping layer plays a role of adjusting the sound insulation amount of the rigid base layer in the low frequency band, and the rigid constraining layer plays a role of improving the noise reduction effect of the elastic damping layer; through setting the porous sound absorption unit and the resonance sound absorption unit, theresonance sound absorption unit is used for adjusting the sound absorption amount of the porous sound absorption unit in the low frequency band to match the noise characteristics of a transformer, through increase of thickness of a first chamber, the peak of a sound absorption coefficient curve gradually moves to the low frequency band, which is favorable for low frequency sound absorption.

The invention discloses a car active noise reduction method based on heuristic dynamic programming, and belongs to the field of active noise reduction methods of noise in car rooms. According to the car active noise reduction method, massive data in a large database of noise information in a virtual environment of a cloud server are initiatively fitted, the rule of noise frequency spectrum characteristics in the database is looked for through a model network and an execution network trained by heuristic dynamic programming, the noise data with the similar frequency spectrum characteristics arefitted together, an off-line expert library having the less data size and reduced and generated from a huge database is established, so that optimization of the noise data is achieved, and the optimal control quantity is provided for a system. According to the innovative mode, the method can overcome the drawback that an existing car active noise reduction method needs to conduct one-by-one real-time operation on the massive data, and through practical testing, the method can fully meet requirements of noise reduction of an actual traffic car under a real road condition, so that the car active noise reduction method has great market prospect and potential economic value.

The invention discloses an adaptive ear canal active noise reduction earphone and an adaptive ear canal active noise reduction method. The earphone comprises a loudspeaker, an audio input module, a microphone, an operation module and a noise reduction processing module, the audio input module, the operation module, the microphone and the loudspeaker are all connected with the noise reduction processing module, and the microphone is arranged in a front cavity of the loudspeaker. The noise reduction method comprises the following steps that 1, an artificial ear acquires calibrated audios to obtain a third frequency response curve and a third phase curve; 2, the microphone acquires the calibrated audios and surrounding sounds simultaneously to obtain a first frequency response curve, a firstphase curve and a second phase curve; 3, the operation module conducts operation according to data obtained in the step 1 and the step 2 and a fixed algorithm to obtain a filter coefficient; and 4, the noise reduction processing module conducts noise reduction processing on the audios by using the filter coefficient. The earphone and the noise reduction method can adapt to the noise reduction requirements of various different ear canals, meet the noise reduction requirement of users and provide a good experience feeling for the users.

The invention provides a muffler, an air conditioner, and a control method for the air conditioner, wherein the muffler includes: a muffler shell made of piezoelectric material, the muffler shell can receive current through wires, and when the muffler shell is connected to the current Mechanical deformation occurs, and the size of the muffler shell changes accordingly with the change of the access current, so that the sound absorption peak frequency of the muffler changes accordingly. The muffler provided by the present invention changes the size of the muffler casing according to the inverse piezoelectric effect of the piezoelectric material by changing the magnitude of the current connected to the muffler at different operating frequencies of the compressor, thereby changing the sound absorption performance curve of the muffler, and changing the sound absorption peak frequency Move to this operating frequency, so as to meet the noise reduction requirements of each compressor operating frequency, so that the muffler has better vibration and noise reduction performance.

The invention relates to a machining template used for manufacturing a flexible micro-hole sound absorbing film and a manufacturing method for the flexible micro-hole sound absorbing film. Compared with the prior art, the defect that a flexible micro-hole sound absorbing film meeting the acoustic noise reduction requirement is hard to manufacture is overcome. The machining template comprises an upper template body. The upper template body is provided with circular hole arrays. Each circular hole array comprises a plurality of circular holes. The upper template body is hinged to a lower template body. When the upper template body is pressed on the lower template body, cylinder arrays are inserted in the circular hole arrays. The diameter of cylinders ranges from 10 microns to 500 microns, and the height of the cylinders ranges from 60 microns to 3.01 millimeters. The diameter of the circular holes is larger than the diameter of the cylinders. The depth of the circular holes is larger than the height of the cylinders. The practicable, economical and environment-friendly manufacturing method and machining device are provided according to the manufacturing complexity of the flexible micro-hole sound absorbing film, and noise reduction requirements of devices of different shapes can be met.

The invention proposes a wood fiber-coir fiber composite sound-absorbing material and a preparation method thereof. The method comprises the steps of: taking wood fiber and coconut fiber and putting them into a mixer; taking urea-formaldehyde resin glue, adding a curing agent to the urea-formaldehyde resin glue, and then adding Foaming agent to obtain glue; add the glue to the mixer, and mix the wood fiber, coconut fiber and glue evenly by stirring; after mixing, put it into the mold for paving and pre-pressing, and then send it into the The hot press is hot pressed to obtain a composite material board with sound-absorbing properties. The composite sound-absorbing material includes evenly mixed wood fiber, coconut fiber, urea-formaldehyde resin glue, curing agent and foaming agent. The present invention uses natural coconut fiber and wood fiber to mix, and the raw materials are renewable materials, which are environmentally friendly and pollution-free; zinc oxide is used as a modifier to improve azodicarbonamide as a foaming agent, so that wood fiber-coir fiber is compounded The sound absorption performance of the material is improved.