115results about How to "Reduce noise intensity" patented technology

An image processing method for executing edge enhancement for an original image includes: extracting edge components based upon the original image; correcting the extracted edge components by attenuating the individual edge components so that a frequency distribution related to intensity of the edge components approximates a Gaussian distribution assuming a specific width; and executing edge enhancement for the original image based upon the corrected edge components.

The invention relates to a decorative fabric, and in particular relates to a multi-combined fiber shading decorative fabric widely applied to the interior of various traffic tools, high-grade hotels, work places and families and a preparation method, belonging to the spinning field. Different performances of various kinds of raw material fibers are optimized and creatively combined together to form a new fabric, thus the synthetic fiber differentiation, deep processing level and grade of domestic synthetic fiber fabrics are improved, and the production method breaks through the traditional production process and technology. The product is high in ductility, low in manufacturing cost and high in decorative aesthetics.

The invention belongs to the technical field of rocket launching, and particularly relates to a water injection, cooling and denoising system for rocket launching. The system comprises outer water injectors, inner water injectors, a lattice girder, a lower water storage device, two water injection main lead pipes and a head water tank, a launching site is provided with the head water tank, the two water injection main lead pipes are led out from the head water tank and are both connected with the lower water storage device, the outer water injectors and the inner water injectors are arranged on the lower water storage device, the outer water injectors are positioned on two sides of a travel portion of a launching platform and parallel to the travel direction of the launching platform, top ends of the outer water injectors are higher than a platform top of the launching platform, tops ends of the inner water injectors are lower than the platform top of the launching platform, and the lattice girder is used fro supporting the outer water injectors and the inner water injectors. The system is developed aiming at bundled rocket launching technical conditions, and is applicable to occasions such as single-nozzle rocket launching test and simulation test adopting similar heat launching technical conditions.

The invention discloses a linkage mechanism of side moulds and a bottom mould of a bottle blowing machine. The side moulds and the bottom mould of the bottle blowing machine are connected by a linkage connecting rod device; the linkage of the side moulds and the bottom mould is realized by opening-closing motion of the side moulds and lifting motion of the bottom mould; the bottom mould descends when the side moulds are opened; the bottom mould ascends when the side moulds are closed until the set position is totally closed. The linkage of the side moulds and the bottom mould is realized by opening-closing motion of the side moulds and lifting motion of the bottom mould, and the linkage mechanism has a simple structure, is easy to manufacture and maintain, and reduces the manufacturing cost and the maintenance cost; each component is matched in a hinging or rolling mode and is free of mechanical shock during motion, so that the fault rate of each component is greatly reduced, the stability of the equipment is increased, the operation speed can be safely increased, the production efficiency is improved, and the noise is reduced at the same time.

The invention discloses a GPS weak signal tracking system based on I / Q branch correlation integral observation filtering. A receiver is used for receiving a satellite signal which is converted into an intermediate frequency signal through down conversion and transmitted to a frequency mixer. The frequency mixer is also used for receiving local sine and cosine reproduction carrier signals outputted by a local carrier digital-controlled oscillator, and outputting a I-branch output signal and a II-branch output signal to a correlation arithmetic unit. The correlation arithmetic unit also receives a local advanced C / A code, an instant reproduction C / A code and a lagged reproduction C / A code, wherein the local advanced C / A code, the instant reproduction C / A code and the lagged reproduction C / A code are generated by a code generator. Results are outputted to an integral eraser, and six-way relevant integral values are generated and outputted to a Kalman filter. The Kalman filter obtains an estimated carrier phase difference, an estimated carrier frequency difference and an estimated code phase difference, and the estimated carrier phase difference, the estimated carrier frequency difference and the estimated code phase difference are transmitted to the local carrier digital-controlled oscillator and the code generator. The system effectively reduces the noise intensity of the satellite signal, can trace the satellite signal better in a weak-signal environment, and improves the tracing precision.

The invention discloses a foreground detection method and a device as well as an adaptive threshold adjusting method and a device. The foreground detection method comprises the following steps: comparing a current input image with a background image of each frame to obtain the difference value points respectively corresponding to pixel points of the current input image; carrying out statistics onthe percentage of the difference value point number, with value more than different thresholds and choosing a threshold suitable for the current input image according to the variation trend that the percentage of the difference value point increases along with the threshold value. Thus, when foreground detection is carried out, the threshold can be adjusted aiming at the monitoring scene with highor low noise, so that the adjusted threshold can be used for judging the foreground pixel points in the image, thereby improving the accuracy of foreground detection and further improving the accuracy of moving object detection and tracking.

The invention relates to a controller design method of a duct type multi-rotor mooring UAV, belongs to the field of control algorithms, and aims at solving the problem that a UAV controller is low incontrol capability and anti-interference capability due to the fact that a present simulation platform of a UAV control system is incapable of optimizing control parameters sufficiently. According tothe controller design method, a finite element analysis method is used, pneumatic characteristic parameters of the total structure of the duct type multi-rotor mooring UAV is analyzed, a dynamic modelof the UAV is established and distribution values for tension control of different motors are obtained according to the pneumatic characteristic parameters, and the pneumatic characteristic parameters are measured; the established model is combined with the measured pneumatic characteristic parameters to establish a control simulation platform of a duct type mooring UAV control system is established in the simulink environment; and a fuzzy PID controller is used to design the duct type mooring UAV control system with mooring cables, and the parameters are improved.

A clock control circuit including a divider unit for dividing a master clock signal at a falling timing of the same to generate a divided clock signal, a multiplier unit for multiplying the master signal by n at a rising timing of the same, and thinning out an n-th clock pulse to generate a multiplied clock signal, and a selector unit for selecting a bus clock signal from multiplied clock signals at a variety of timings, derived from the multiplied clock signal, and the divided clock signal in accordance with a selection signal, and supplying the selected signal to a processor.

A method for processing a digital gray value image includes the steps of: generating a binary edge image from the gray value image so that edges present in the gray value image are determined as line areas around the edges; applying a sharpness algorithm in the gray value image within regions which correspond to the line areas; and, carrying out a smoothing process in the gray value image within regions which lie outside of the line areas so that an additional smoothed, sharpened gray value image is generated.

A power supply device and a luminaire which are capable of keeping the output of the load constant and reducing noise intensity are provided. According to one embodiment, the power supply device includes a rectifying circuit configured to rectify an alternating-current power supply and a power-supply-voltage converting section. The power-supply-voltage converting section includes a plurality of power-supply-voltage converting circuits provided between the rectifying circuit and a plurality of output sections to which loads are respectively connected. Switching elements configured to convert a power supply voltage rectified by the rectifying circuit and supply the power supply voltage to the loads are provided in the plurality of power-supply-voltage converting circuits. The switching elements of the plurality of power-supply-voltage converting circuits are set to at least two different switching frequencies and turned on and off with the respective switching frequencies fixed.

The invention discloses a weapon bay noise suppression device based on environment gas jet. The weapon bay noise suppression device is installed at an opening of a weapon bay (11) and comprises a plenum chamber (2) which is connected along an airflow direction and is provided with a small opening and a large cavity, and a jet flow opening cover (4) provided with a jet flow outlet (6), wherein the jet flow outlet (6) with long and thin rectangular cross section is positioned at the front edge of the weapon bay (11). The weapon bay noise suppression device is installed inside the weapon bay, environment gas is utilized as an air source, the intensity of noise in the bay when the weapon bay is started is reduced by spraying gas flow to the opening of the weapon bay, the aerodynamic configuration of an aircraft cannot be damaged, also high-pressure air source does not need to be additionally supplied, the service life is long, and stable and reliable effects are achieved.

The invention relates to a duct type multi-rotor tethered drone and a control system thereof, belongs to the field of drones, and aims to solve the problems that existing drones are short in flight duration and prone to crash due to the fact that the rotors of the drones are exposed. The duct type multi-rotor tethered drone is characterized in that the an inner central pipe is connected with an outer duct pipe through a group of guide vanes, a group of carbon fiber pipes is fixedly mounted on the outer wall of the lateral side of a block formed by central plates, the middle section of each carbon fiber pipe is fixed with the wall of the duct pipe, and an auxiliary rotor is mounted at the tail end of each carbon fiber pipe through an auxiliary motor; a hardware control system is mounted onthe upper surface of the central plate block, a main motor is coaxially mounted on the lower surface of the central plate block, the main motor drives a main rotor, and a power supply system is arranged beside the main motor; the hardware control system is connected with the main motor, a group of auxiliary motors, the power supply system, a video collecting unit and an automatic pilot, and a tether is connected with the hardware control system, the main motor, the group of auxiliary motors and the video collecting unit through the power supply system. The duct type multi-rotor tethered dronecan constantly work around the clock.

The invention belongs to the technical field of multi-rotor unmanned aerial vehicle classification, and particularly relates to a micro Doppler spectrum correlation matrix feature extraction method ofa multi-rotor unmanned aerial vehicle. According to the method, firstly, short-time Fourier transform (STFT) is carried out on echo data of rotors of the multi-rotor unmanned aerial vehicle to obtainmicro-Doppler spectrum data, and then correlation matrix characteristics are extracted by utilizing the micro-Doppler spectrum data to realize identification of the multi-rotor unmanned aerial vehicle. Due to the fact that the extracted correlation matrix features only contain the micro Doppler information of the strong scattering points on the rotating blade and noise intensity is reduced, compared with physical parameter features extracted from time-frequency spectrum data, the method has better robustness to noise, and a higher recognition rate can be obtained even under the condition of alow signal-to-noise ratio.

The invention relates to a denoising method for reducing noise on a traffic passage through a sponge plate. The technical proposal is that a sponge plate is installed at a proper position of the traffic passage to absorb and consume noise energy and to reduce noise intensity in and out of the traffic passage. The sponge plate with thickness of 5mm-500mm is made of flame-retarding sound absorbing sponge with undulated surface, and the color and the pattern of the appearance of the sponge plate can be chosen according to landscape feature. The denoising method has the technical effects that the sponge plate is porous and elastic; the porous structure enables the sound waves to permeate smoothly and helps to avoid reverberation, and the elasticity enables the sponge to deform to further absorb noise energy, thus effectively reducing noise intensity. The sponge plate is easy to disassemble, wash and replace. The sponge plate on a wall can have cushioning function when a motor vehicle crashes the wall. The denoising method is applicable to the denoising, cushioning and decoration of motor vehicle tunnels, motor vehicle subways, railway tunnels, roads, highways, overhead roads, ground railways and railway overhead passages.

In the falling water noise reducing plate for cooling tower, each silencing pipe includes successively connected five sections, one vertical section, one first inclining section, one second inclining section, one turning reflux section and one stretching curve section. The vertical section in the upper part can guide falling water without noise; the two inclining sections in the middle part can silence water falling through slant friction and reduce water flow speed; and the turning reflux section and the stretching curve section in the lower part can dissipate the energy of falling water and further lower the noise of falling water by means of pores and corrugated grooves and sound wave interference. The present invention has ideal noise reducing effect.

The invention relates to a low-noise drainage pipeline. The low-noise drainage pipeline comprises a pipeline body. The low-noise drainage pipeline is characterized in that the surface of the inner wall of the pipeline body is provided with a plurality of protrusions to form an unsmooth surface of the inner wall of the pipeline. Compared with the prior art, the low-noise drainage pipeline has the advantages that the protrusions are arranged on the inner wall of the drainage pipeline to form a non-sticky structure, the unsmooth surface is formed on the non-sticky structure, the energy of sound waves is absorbed based on the lotus leaf surface tension principle, a water flow fracture face structure and a local water flow direction are changed, the frequency of noise produced by friction between the water flow and the pipe wall is fairly reduced, resonance produced by noise caused by flowing of fluid in a sewer is weakened, and finally the purpose of lowering noise of the sewer and a water channel is achieved. The experimental result shows that the noiseless effect is obviously superior to that of other pipelines, and the noise of the plastic pipeline is lower than 45 decibels.

The invention belongs to the technical field of unmanned aerial vehicle identification, and particularly relates to a singular-vector-based multi-rotor unmanned aerial vehicle physical parameter extraction method. The method comprises the following steps: firstly, performing wavelet decomposition on a radar echo signal of the multi-rotor unmanned aerial vehicle, extracting a low-frequency component generated by a blade rotating part, and then performing time-frequency analysis on the component to obtain a micro-Doppler spectrogram; and extracting physical parameters such as the rotating speedand the blade length of the rotor by using the singular vector corresponding to the maximum singular value of the micro Doppler frequency diagram. Physical parameters can be directly extracted in combination with left and right singular vectors, so that the estimation accuracy is improved, and accurate features are provided for recognition of the multi-rotor unmanned aerial vehicle. Besides, through wavelet analysis on echo data, the noise intensity in echo signals is reduced, and physical parameters such as the rotating speed and the blade length can still be accurately extracted under the condition of a low signal-to-noise ratio. A simulation experiment result verifies the effectiveness of the method.

An angular velocity measuring device measures an angular velocity of a gear that is fixed to a rotary shaft. The angular velocity measuring device includes a pair of magnetic sensors that are arranged at positions facing a tooth flank of the gear and that detect a shape of the tooth flank in a noncontact manner, and a computation unit that is configured to generate a waveform obtained by synthesizing output detection signals of the pair of the magnetic sensors with each other and output an output waveform and calculate the angular velocity of the gear from the output waveform. The magnetic sensors are arranged such that the output detection signals are offset from each other by {(n−1)+(⅙)} pitches when one pitch is defined as one cycle of the shape of the tooth flank in a circumferential direction of the gear.

The invention discloses an active earphone noise reduction method suitable for a ship high-noise scene, and belongs to the technical field of noise reduction earphones. The method comprises the following steps: (1) after a feed-forward microphone collects environmental sound information, obtaining an inverted noise signal, namely a feed-forward noise reduction signal, and forming a feed-forward anti-noise wave; (2) synchronizing with the step (1), acquiring audio information near the ear by a feedback microphone, generating a feedback noise reduction signal, and forming a feedback anti-noise wave; and (3) receiving the feed-forward noise reduction signal and the feedback noise reduction signal at the same time, and outputting at least one of the two signals to the moving coil driving unitby the function management module. The active noise reduction system based on wavelet transform, feedforward and feedback fusion is achieved, the noise reduction mode of the active noise reduction system can be effectively and flexibly adjusted according to the environment, the requirement for reducing noise on a ship can be well met, and a good noise reduction effect can also be maintained in theenvironment where the noise of the ship changes drastically.

A display apparatus has a clock generating circuit, a drive waveform generating circuit, and a display panel. The drive waveform generating circuit is used to generate a drive waveform by using a clock from the clock generating circuit, and the display panel is used to display an image in accordance with the drive waveform. The clock generating circuit generates a clock whose frequency varies continuously. The drive waveform generating circuit drives the display panel by outputting a drive waveform whose frequency varies in accordance with the frequency varying clock so as to spread out noise that the display panel emits. Therefore, peak values of the noise can be reduced.

The invention discloses a sound guide device which is used for a range hood. The device comprises a mounting seat. The mounting seat comprises a cavity. A plurality of sound guide sheets are arrangedin the cavity and divide the cavity into a plurality of sound guide channels. Each sound guide channel comprises a depth and a width, and a ratio of the depth and the width of each sound guide channelis not less than 1. Through research, a noise of the range hood is concentrated in a medium-high frequency band which is above 500 HZ. A noise wavelength is short, such as light waves and other short-frequency waves, and certain directivity is realized in nature. In the invention, the plurality of sparse sound guide plates with a certain depth are used for constraining a noise (the most importantway of transmitting the noise to the indoor during actual use) transmitted from an exhaust inlet of the range hood, and the sound guide plates directionally transmit the sound waves of medium-high frequency bands so that the sound waves are not directly emitted to ears, intensity of the noise received by the ears is reduced, and use experience of people is improved.

The invention relates to the technical field of air outlet noise reduction of air conditioners in cabs, in particular to an air outlet device, an air conditioner and engineering machinery. The air outlet device comprises an air outlet structure, wherein the air outlet structure comprises an air outlet body with an air outlet and an air baffling plate arranged inside the air outlet; an airflow flows through the air outlet and flows out of the air conditioner; the air baffling plate adjusts the opening degree of the air outlet by changing the angle relative to the air outlet body; the air outlet device further comprises an air outlet noise-reducing device; the air outlet noise-reducing device can reduce noise at the air outlet structure; the air outlet noise-reducing device is arranged at the upstream of the air outlet structure in the outflowing direction of the airflow. The air outlet device can treat the airflow by using the air outlet noise-reducing device before the airflow reaches the air outlet structure, so that the noise at the air outlet structure is relatively reduced, the noise intensity in a cab is reduced, and the sound quality in the cab is improved.

The invention relates to a quaternary phase-shift keying signal tracking method and device, which are applied to a GNSS (Global Navigation Satellite System) receiver. Under the combined tracking mode of in-phase and orthogonal dicode channels, the method comprises the following steps of: carrying out correlation operation respectively with corresponding local PRN (Pseudo-Random Noise) codes on an in-phase (I) code channel signal and an orthogonal (Q) code channel signal after down-conversion, and outputting the integral results of the I code channel signal and the Q code channel signal; respectively carrying out identification on the integral results of the I code channel signal and the Q code channel signal in at least one tracking loop so as to obtain identification results; and carrying out mathematic operation on the identification results of the I code channel signal and the Q code channel signal in the same tracking loop so as to obtain a synthesized identification result. In the tracking loop, the corresponding devices comprise an I code channel identifier, a Q code channel identifier and a synthetic identifier. According to the quaternary phase-shift keying signal tracking method and device, the noise intensity of the tracking loops such as DLL (Dynamic Link Library), PLL (Phase Locked Loop) and FLL (Fixed Loss Loop) is obviously reduced.

The invention discloses a micro-perforated resonant cavity muffling structure and a noise-reduction muffler for auxiliary power units (APU). The micro-perforated resonant cavity muffling structure comprises an inner cylinder assembly and an outer cylinder; the outer cylinder is in a hollow cylinder shape, a cavity is formed in the outer cylinder, and through openings leading into the outer cylinder are formed in the two ends of the outer cylinder; the inner cylinder assembly penetrates through the outer cylinder through the through openings and is fixedly connected with the outer cylinder through a plurality of structures; a plurality of muffling through holes are formed in the inner cylinder assembly, muffling partition plates serve as supporting structures, the muffling partition platesare circular partition plates, the muffling partition plates and the inner cylinder assembly are coaxially arranged, and the outer edges of the muffling partition plates are fixedly connected with theinner wall of the outer cylinder; and the inner cylinder assembly comprises a plurality of muffling acoustic liners which are sequentially connected end to end, the muffling partition plates are coaxially arranged outside the junctions of all the muffling acoustic liners, and muffling through holes are formed in all the muffling acoustic liners. According to the micro-perforated resonant cavity muffling structure, the structure form of a large resonant cavity is adopted, the weight of equipment is greatly decreased, structure stiffness is improved, and the intensity of noise transmitted in aworking state of the APU is weakened.

The invention discloses box type non-negative pressure water supply equipment, and belongs to the technical field of water supply equipment. The box type non-negative pressure water supply equipment comprises a water supply box, a water supply pump and a bottom plate, the water supply box, a water pump seat and a control box are fixedly mounted at the top of the bottom plate, the water supply pump is fixedly mounted at the top of the water pump seat, a top groove is formed in the top surface of the bottom plate, a water pumping assembly is arranged on the outer wall of one side of the water supply pump, a buffer vibration guide mechanism is arranged outside the water supply pump through a buffer ring, and a water diversion pipe is fixedly mounted on the other side wall of the water supply pump. According to the box type non-negative pressure water supply equipment, the buffering vibration guide mechanism is arranged outside the water supply pump, and on the one hand, the buffering vibration guide mechanism can effectively relieve vibration generated during work of the water supply pump; and on the other hand, unavoidable vibration is utilized and compensated reversely, the effect of dredging in a pipe without an additional driving source is achieved, the situation that the interior of the pipe is blocked due to impurity gathering and caking caused by alternate cooling and heating is effectively avoided, and the working effect of equipment is greatly improved.

The invention discloses a method and system for conducting refrigeration through noise sound waves. The system comprises a sound wave reception intensifier, a refrigeration container and a gas circulation system. The sound wave reception intensifier is used for receiving noise sound waves and intensifying pulses of the noise sound waves. The refrigeration container is used for receiving the intensified pulses of the noise sound waves sent by the sound wave reception intensifier, and compressing refrigeration gas in the compression container through the pulses of the noise sound waves. The gas circulation system is used for receiving the compressed refrigeration gas conveyed from the refrigeration container so that pipelines can be filled with the refrigeration gas. The pipelines at different positions are opened, and therefore the refrigeration gas expands to absorb heat in the surrounding environment. By means of the system, the refrigeration cost of a data center is saved, and noise is reduced.

The invention discloses a double-compressor air energy heat pump heat supply heating system, and belongs to the technical field of air energy heat pump heat supply heating. The double-compressor air energy heat pump heat supply heating system comprises a compressor shell and a water tank shell, wherein a double-compressor main body is fixedly installed in the compressor shell; a damping spring is fixedly installed between the side wall of the double-compressor main body and the inner wall of the compressor shell; an air inlet assembly is fixedly installed on the side wall of the double-compressor main body; sound absorption and noise reduction assemblies are rotatably installed at the positions, located in the compressor shell, of the two sides of the double-compressor main body; and a built-in water tank is fixedly installed in the water tank shell. According to the double-compressor air energy heat pump heat supply heating system provided by the invention, the sound absorption and noise reduction assemblies are arranged in the compressor shell, meanwhile, a side striking assembly is arranged outside the double-compressor main body, and when the system works in ordinary times, through the linkage effect, unavoidable vibration generated when compressors work is utilized, so that the excellent noise reduction effect on the compressors is achieved, waste is turned into wealth, the design is ingenious, and the overall use quietness of the system is improved.

The invention discloses a compound exhausting emptying silencer which comprises a rainproof sound-absorbing umbrella cap, an expanding gradual changing pipe, a first level throttling pressure-reducing pipe, a second level throttling pressure-reducing pipe, a throttling pressure-reducing top plate, a blocking sound-absorbing layer, a silencer drum and a mounting force-bearing structure, wherein a bottom port of the expanding gradual changing pipe is connected with the top of an emptying pipe through a flange; an upper port is connected with the first level throttling pressure-reducing pipe; a pipe wall of the first level throttling pressure-reducing pipe is provided with a first-level throttling hole; the second level throttling pressure-reducing pipe and the first level throttling pressure-reducing pipe are both arranged as concentric circular pipes; the pipe wall of the second level throttling pressure-reducing pipe is provided with a second-level throttling hole; a circular air outlet is formed on the upper part of the silencer drum; the rainproof sound-absorbing umbrella cap is arranged on the upper part of the air outlet. The compound exhausting emptying silencer has the advantages of silencing effect more than or equal to 45dB(A), small volume, high strength, convenience in mounting and capability of preventing invasion of sand storm, rain, snow and water.

The invention provides a bone conduction microphone and a head-mounted Bluetooth earphone. The bone conduction microphone comprises a shell, a surface cover and a bone conduction assembly, the surface cover is provided with a first surface and a second surface, the first surface faces the front cheek part of the ear, the first surface and the front cheek part of the ear are arranged in a clearance mode, and the second surface corresponds to the first surface; the bone conduction assembly comprises an air bag and a bone guide plate sealed at an opening of the air bag; wherein an airtight cavity defined by the air bag and the bone guide plate is filled with inert gas, and the end, away from the opening of the air bag, of the air bag penetrates through a through hole in the face cover and protrudes out of the first face till abutting against the front cheek portion of the ear, so that the air bag senses vibration of the front cheek portion of the ear; and the surface cover is used for blocking vibration of external noise sound waves to the air bag. According to the bone conduction microphone, the structure of the bone conduction microphone is optimally designed, the physical sound insulation performance of the headphone is improved to the maximum extent, the signal-to-noise ratio of the headphone is improved, and voice signals can be clearly transmitted to a receiver in a high noisy environment.

An optical pick-up and a disc apparatus having the same to overcome an inferiority of a tracking signal caused by an adjacent layer during the recording and / or reproducing of an optical disc with multiple recording layers, the optical pick-up including: a light source to emit light with a wavelength corresponding to a type of the optical disc; a light collecting unit to focus the light emitted from the light source to form a light spot on a signal recording layer of an optical disc having a plurality of recording layers; a photodetector to receive a signal light reflected by the signal recording layer and a noise light reflected by an adjacent recording layer different from the signal recording layer, and to detect a signal from the signal light; and an optical member to change an optical transmission of the noise light according to an incident angle of the noise light so as to decrease an intensity of the noise light entering the photodetector.