172 results about "Noise measurement" patented technology

Disclosed in the present application are a server, and an aerodynamic-noise and heat-dissipation optimization control system therefor. The system comprises a heat dissipation fan, a temperature measurement module, a noise measurement module, a power consumption measurement module, a controller and a phase-change air guide cover, wherein the aerodynamic area of the heat dissipation fan is adjustable; the temperature measurement module is used for measuring the temperature of a case; the noise measurement module is used for measuring the noise inside the case; the power consumption measurement module is used for acquiring a load requirement of a program currently running in a server; and the controller is used for adjusting the working condition of the heat dissipation fan, analyzing the lowest operating power of each server assembly on the basis of the load requirement when internal noise reaches a preset threshold value, and adjusting the current power of each server assembly on the basis of the lowest operating power. The phase-change air guide cover is used for guiding air and absorbing heat by means of a phase-change material.

The invention relates to the technical field of noise measurement systems, in particular to a noise measurement system for a new energy tire, which comprises a tire positioning and driving unit, a sensor unit, a data acquisition and synchronization unit, a data processing unit, a data analysis unit and a man-machine interaction and display unit, the tire positioning and driving unit simulates different loads, different speeds and different road conditions of a tire by using a rack type tire positioning device, and drives the tire to rotate by using a brushless mute motor, so that a high-speed rotating effect without introducing extra mechanical noise is realized; the sensor unit is arranged on the two sides of the tire and at the position close to the ground through an acoustic sensor free field type condenser microphone array, is fixed to the suspension support through an acceleration sensor and is used for collecting vibration signals; the running states of the tire under different loads, speeds and road conditions are accurately simulated, noise data of the tire under various actual working conditions are obtained, and the measurement result is closer to the real situation.

The invention relates to a method for detecting self-moving objects in a motor vehicle, in particular using sparse or noisy measurement data (1, 2). It comprises detecting the surroundings of the motor vehicle, classifying (6) and indexing (8) self-moving objects, determining temporal offsets between current and time-shifted measurement data (1, 2), and extracting and transforming feature data. A transformer network and an attention mechanism are used to generate feature vectors (17) and assign cost values ​​(19) to them. These are then fed into an association function (20), which identifies self-moving objects based on the assigned cost values ​​(19). Based on this, a control device of the motor vehicle is controlled and / or a notification is provided to the driver.

The invention discloses a woodworking machine tool noise sound power level measurement method based on a sound intensity method, and belongs to the technical field of machine tool noise measurement, and the method specifically comprises the steps: determining a housing surface covered by a tool rotation plane projection as a main sound radiation region, and determining a main bearing pedestal installation surface as an infrasound radiation region; sound pressure, vibration acceleration signals and dynamic air pressure signals of a main sound radiation area are collected; resampling a dynamic air pressure signal rotation angle domain, extracting a reference pneumatic pulsating waveform synchronous with tool tooth sweeping, and establishing an airflow induced sound pressure model according to the reference pneumatic pulsating waveform and a phase relation; calculating a surface normal vibration speed according to the vibration acceleration, and establishing a structure radiation sound pressure model in combination with a sound wave equation; decomposing the sound pressure signal to obtain two types of component estimation values, and performing parameter optimization to obtain net sound intensity of a main sound radiation area; extracting vibration frequency band energy of an infrasound radiation area, calculating equivalent sound intensity by combining a sound radiation efficiency model, and outputting a total sound power level by space integration; the invention provides an effective method for accurately measuring and controlling the noise of the woodworking machine tool.

The invention discloses a self-supervised tomographic SAR (Synthetic Aperture Radar) reconstruction method based on orthogonal subspace decomposition. According to the method, a traditional single original space is reconstructed and expanded into a Range-Null-Raw triple space collaborative learning framework, an R2R and N2N principle-based self-supervised loss function is constructed by using an orthogonal subspace decomposition characteristic of a linear measurement operator, direct mapping learning from noise measurement data to a high-quality reconstruction result is realized, and the real-time performance of a real-time reconstruction system is greatly improved, so that the real-time performance of the real-time performance of the real-time performance of the real-time performance of the real-time performance of the real-time performance of the real-time performance is improved. Observable components are learned through Range space, unobservable components are learned through Null space, a cross constraint strategy of global consistency is ensured through Raw space, and the adaptability of the model to real measurement conditions is enhanced. The performance gap between simulation training and actual deployment in deep learning TomoSAR reconstruction is effectively solved, and a new solution is provided for reliable application of an unsupervised deep reconstruction network in a real TomoSAR imaging task.

An integrated circuit device includes a multiplexor and multiple receivers for high-speed data communication interfaces. The multiplexor includes multiple signal inputs, a selector input, and a signal output. Each receiver includes a differential data signal input including a positive signal input and a negative signal input, a first termination resistor to terminate the positive signal input to a reference voltage node, a second termination resistor to terminate the negative signal input to the reference voltage node, and a noise measurement node to detect common mode noise at the reference voltage node, the noise measurement node coupled to an associated one of the signal inputs.

A method of determining residual intensity noise (RIN) of a sensor may comprise determining a first amplitude of a first harmonic of the sensor while a signal propagating through the sensor is modulated at a modulating frequency corresponding to twice an eigenfrequency of the sensor. The method may further comprise determining a second amplitude of a second harmonic of the sensor while the signal propagating through the sensor is modulated the modulating frequency, and determining the RIN of the sensor as a ratio of the first amplitude and the second amplitude.

The invention relates to the technical field of servo system control, in particular to a noise measurement suppression method and device based on axial angle tracking angular position estimation. The method comprises the following steps: determining a first measurement angle after sine transformation and a second measurement angle after cosine transformation based on the first measurement angle and the second measurement angle; simplifying the first measurement angle after sine transformation and the second measurement angle after cosine transformation to obtain a simplified first measurement angle and a simplified second measurement angle; based on the simplified first measurement angle and the simplified second measurement angle, determining a representation relation between a phase discriminator tracking error of the servo system and a phase-locked loop output angle; determining an input of the servo system based on the representation relationship; determining an estimated angle value based on the input of the servo system and a preset closed-loop transfer function; and controlling the servo system based on the estimated angle value. Therefore, the control precision of the servo system can be improved.

The invention provides a noise acquisition device and a noise measurement device of an operational amplifier. The noise acquisition device comprises a preset resistor matched with a target operational amplifier, a total noise acquisition circuit and a resistance noise acquisition circuit, the total noise acquisition circuit acquires the total noise of the current working environment and amplifies the total noise so as to output the amplified total noise to external preset measurement equipment; the resistance noise acquisition circuit acquires and amplifies first noise correspondingly generated by the preset resistor in the current working environment and carries out amplification processing so as to output the amplified first noise to preset measurement equipment. The total noise and the first noise are collected, the first noise is used for compensating the total noise to obtain the noise of the target operational amplifier, and the defects that measurement cannot be conducted due to the fact that the bottom noise of the spectrum analyzer is too large and the measurement accuracy is reduced due to the first noise are overcome; low-ripple positive and negative direct-current power supply voltage is provided, and the size is small; the spatial noise coupling interference is reduced, and the accuracy is improved.

The application discloses a time difference positioning method based on random robust least square, mainly solves the threshold effect of the existing time difference positioning method when the measurement error increases, and leads to the problem of sharp deterioration of positioning accuracy, and the implementation scheme is as follows: a plurality of observation stations and noise measurement errors are set, the time difference positioning equation is obtained by using the position parameters and the measurement errors, an auxiliary variable is defined, the auxiliary variable is introduced into the time difference positioning equation to establish a constraint equation, the constraint equation is processed by using a random robust least square method to obtain a cost function, the cost function is solved by using a least square method to obtain a target position, a new constraint equation is established according to the internal relation of the auxiliary variable elements, the new constraint equation is solved by using a weighted least square method to obtain a positioning error, the target position is linearly corrected by using the positioning error to obtain a final positioning result, and the target positioning is completed. The application reduces the positioning error, improves the positioning accuracy and the robustness of positioning, and can be used in aerospace, navigation and electronic warfare.

The present invention discloses an adjustable submersible noise measurement system, comprising an underwater instrument cabin, an optoelectronic transmission cable, an optical fiber hydrophone array, an expander, a mooring device, and a surface communication buoy. The optical fiber hydrophone array receives noise signals radiated by underwater targets and transmits the signals to the underwater instrument cabin via the optoelectronic transmission cable. The underwater instrument cabin is fixed to the seabed by the mooring device and connected to the surface communication buoy. The expander is fixed to the seabed by a hook anchor, and the optical fiber hydrophone array is adjusted by the expander to achieve horizontal deployment. The underwater instrument cabin and the expander are positively buoyant structures, thereby forming a trapezoidal structure underwater. The present invention utilizes the expander to retract and extend the optoelectronic transmission cable and hook anchor to control the entire array to be horizontal underwater and stabilize the array's posture. When the array's posture reaches the required posture for equipment testing, the expander stops working, and the equipment is now in a silent state and does not generate any noise, thereby reducing the impact of noise generated by the equipment itself.

The invention discloses a city design noise optimization method and system based on artificial intelligence, and the method comprises the steps: carrying out the preprocessing of building form and noise measurement data, and constructing a basic data set after noise simulation verification; a three-dimensional city model and a measuring point network are generated through a layered parameterization framework, the structural noise level is calculated, real-time verification is carried out in combination with planning constraints, and a structural design space, noise basic data and feasibility guarantee are provided; a two-stage multi-layer perceptron network is constructed, local building group acoustic influence and a global city noise mode are processed respectively, and high-precision noise prediction is achieved through training; and deploying a large language model as an optimization agent, and outputting an optimal scheme through multiple rounds of iterative optimization and evaluation. Compared with the prior art, the method has the advantages that the noise prediction precision is effectively improved, a structured design space is provided for parametric modeling, the feasibility is guaranteed through real-time verification, efficient iteration is achieved through large language model optimization, and compared with a traditional method, the efficiency is remarkably improved, and the labor cost is reduced.

The application provides a kind of transport aircraft cabin top structure noise multi-point measurement method under flight full working condition, and belongs to the technical field of aircraft noise testing.The application uses cargo compartment lifting slide rail as existing installation datum, and forms adjustable measurement point layout structure by telescopic cross bar device and height adjusting lifting rod, so that fast installation, stable fixation and spatial positioning of noise testing sensor in the top area of transport aircraft cabin can be realized without damaging original structure of aircraft body.The application can execute multi-point noise measurement of complex environment in the top area of aircraft cabin without changing original structure of transport aircraft, so that sensor can be stably and reliably installed in flight vibration environment, and effective coverage and accurate identification of key noise area in the top area can be realized.

The present invention relates to a sensor device for attachment to an equipment shell, the device comprising a casing (1) configured for attachment to an equipment shell by means of a fastening system comprising a bushing (4) with a cylindrical part internal to the casing and a flange part (4a) configured to contact the equipment shell when the device is attached to it, the casing (1) housing a plurality of sensors for measuring data related to the operating condition of the equipment, at least one processor configured to receive the data measured by the sensors; and at least one means of wireless communication for communication with a server remote to the device, in which the casing (1) comprises a casing body (2), which receives, at one end, a printed circuit board (11) which receives an acoustic sensor (12) for structural noise measurement, the printed circuit board (11) being in contact with the flange part (4a) of the bushing (4).

A hearing protection device to be worn in ear provides communications of ambient sound to an in-ear speaker. Blast noise is detected and measured using either the in-ear speaker as a microphone or using a separate in-ear microphone.

The invention relates to a measurement and inversion reconstruction method for a helicopter rotor sound radiation ball in an acoustic wind tunnel, and relates to the technical field of helicopter aeroacoustics wind tunnel test technology and sound target characteristics, and the method comprises the steps: measuring the noise radiated by a helicopter rotor in the acoustic wind tunnel through a hemispherical far-field noise measurement device; noise signals of the rotor in different directions are obtained, and a rotor sound radiation ball model is constructed; based on a sound propagation theory in a flow field, constructing a propagation model from the surface of the sound radiation ball model to the position of a microphone, and based on the influence of background noise, establishing a sound propagation equation from the surface of the sound radiation ball model to the microphone in the hemispherical far-field noise measurement device; and converting the sound propagation equation into solving a least square problem, solving to obtain sound source distribution on the surface of the sound radiation ball model, and reconstructing noise at any position of the far field of the helicopter rotor. The method can be suitable for reconstructing the helicopter rotor sound radiation ball in complex environments such as acoustic wind tunnels and high background noise, and practical research and application are carried out.

The utility model relates to the technical field of measuring devices, in particular to a noise measuring device with a telescopic function, which comprises a fixed cylinder, a dustproof cloth bag is sleeved on the outer side of the fixed cylinder, an elastic rubber belt is fixedly connected on the outer side of the dustproof cloth bag, a pair of magnetic blocks is fixedly connected on the outer side of the elastic rubber belt, and the magnetic blocks are fixed on the fixed cylinder. A sliding rod is slidably connected to the side face of the inner wall of the fixing cylinder, a sliding rod is fixedly connected to one end of the sliding rod, and a telescopic assembly is arranged in the fixing cylinder. According to the noise meter, the micro motor, the winding roller, the traction rope, the sliding rod and the spring are arranged in a matched mode, automatic shrinkage of the noise meter body is achieved through take-up and pay-off of the winding roller, and through matched arrangement of the dustproof cloth bag, the magnetic block and the elastic rubber belt, when the noise meter body is shrunk to the position closest to the fixing cylinder, the noise meter body is prevented from falling off. The noise meter body is wrapped and protected through the dustproof cloth bag.

The invention discloses a heat recovery fresh air handling unit noise measurement auxiliary device and a test method thereof.The auxiliary device comprises a noise elimination cover and a noise elimination air pipe, the noise elimination cover is defined by noise elimination walls, an inner groove is formed in the lower face of the noise elimination cover, mounting holes are formed in the two ends of the inner groove respectively, and the mounting holes communicate with the interior and the exterior of the noise elimination cover; a silencing air pipe is arranged corresponding to each mounting hole, one end of each silencing air pipe is located in the corresponding inner groove and used for being connected with a heat recovery fresh air handling unit, the other end of each silencing air pipe penetrates into the silencing cover through the corresponding mounting hole, and a static pressure ring is arranged at the end, connected with the heat recovery fresh air handling unit, of each silencing air pipe and connected with a digital micromanometer. An electric air valve is arranged at the end, penetrating into the silencing cover, of each silencing air pipe. According to the testing method, the heat recovery fresh air handling unit is hoisted in the semi-anechoic chamber through the auxiliary device to be tested. The structure of the original semi-anechoic chamber cannot be damaged through the auxiliary test, and the test cost is reduced.

The invention relates to a noise measurement method and device, electronic equipment and a storage medium, and the method comprises the steps: generating a noise measurement task based on pre-recorded noise data and to-be-measured site information; arranging a plurality of noise measurement recording devices based on the noise measurement task, and collecting audio data by using the plurality of noise measurement recording devices; judging whether target audio data exists in the audio data based on the pre-recorded noise data; and based on a preset storage mode, storing the target audio data while storing the audio data so as to perform noise data analysis by using the audio data and / or the target audio data. Therefore, the technical problems that different noise targets are difficult to distinguish and accurate analysis and comparison are difficult to carry out when the environmental noise is collected in the prior art are solved.

To provide an EMC countermeasure presentation system capable of efficiently extracting and presenting an emission countermeasure case in another field and another model with high similarity (countermeasure effectiveness) in consideration of a device configuration of an electronic apparatus.SOLUTION: A similar configuration extraction unit 3 configured to extract, based on device configuration data 11 at the time of noise measurement, device configuration data at a short distance by configuration learning data 9 obtained by learning a graph model representing a device configuration when the noise countermeasure and reduction amount frequency data is acquired; and a countermeasure estimation unit 4 configured to estimate, from data obtained from the reduction countermeasure extraction unit and the similar configuration extraction unit, a recommended countermeasure content having a high degree of similarity of a device connection configuration and expected to have an excessive noise reduction effect.SELECTED DRAWING: Figure 1

This invention discloses a method for measuring the sound power level of woodworking machine tool noise based on the sound intensity method, belonging to the field of machine tool noise measurement technology. Specifically, it includes: determining the housing surface covered by the projection of the tool's rotation plane as the main sound radiation area, and the main bearing seat mounting surface as the secondary sound radiation area; acquiring sound pressure, vibration acceleration signals, and dynamic air pressure signals in the main sound radiation area; resampling the dynamic air pressure signal in the rotational angular domain, extracting the reference air pulse waveform synchronized with the tool tooth sweep, and establishing an airflow-induced sound pressure model based on this and the phase relationship; calculating the surface normal vibration velocity based on the vibration acceleration, and establishing a structural radiation sound pressure model based on the sound wave equation; decomposing the sound pressure signal to obtain estimates of two types of components, and obtaining the net sound intensity of the main sound radiation area after parameter optimization; extracting the vibration frequency band energy of the secondary sound radiation area, calculating the equivalent sound intensity based on the sound radiation efficiency model, and spatially integrating to output the total sound power level. This invention provides an effective method for the accurate measurement and control of woodworking machine tool noise.

The invention discloses a measuring system with a front transmitting power amplifier and a measuring method, and relates to the technical field of noise measurement. By arranging the noise measurement assembly and the measurement rod assembly, the noise measurement assembly can simulate a profiling measurement motion trail according to the outer contour shape of the transformer through an adjustable profiling rod and guide wheel structure, so that a guide wheel is always in contact with the outer wall of the transformer, and elastic adjustment of a spring is matched; a preset stable detection distance can be kept between the measurement end of the measurement assembly and the outer wall of the transformer, and the adaptive capacity of dynamically adjusting the position of the noise measurement mechanism according to the shape of the outline of the transformer avoids errors caused by large-range fluctuation of a traditional measurement distance, so that the precision of multi-point measurement data is remarkably improved; and the noise measuring mechanism is internally provided with a front transmission power amplifier, so that the acquisition capability of weak noise signals can be enhanced, the method is particularly suitable for fine detection of a low-noise transformer, and the signal acquisition definition is improved.

The present disclosure relates to test and / or measurement system including a base unit with a test ports connectable to a DUT. The base unit includes a port unit connected to one of the test ports. The port unit includes an image-free receiver circuit. An input of the circuit is connected to the one test port. The system includes an ADC unit. An output of the circuit is connected to the ADC unit. A signal source generates a stimulus signal and / or a known noise source to generate a noise signal. If the system operates in an S-parameter measurement mode, the stimulus signal is feedable to a first port of the DUT; and / or, if the system operates in a noise measurement mode, the noise signal is feedable to the first port or to a second port of the DUT. The input connects to the first or second port of the DUT.

The present application relates to a kind of acoustic wind tunnel inside helicopter rotor sound radiation sphere measurement and inversion reconstruction method, it is related to helicopter aerodynamic acoustics wind tunnel test technology and acoustic target characteristic technical field, include: in acoustic wind tunnel using hemispherical far-field noise measuring device measurement helicopter rotor radiated noise, obtain the noise signal of different azimuth of rotor and construct rotor sound radiation sphere model;Based on the sound propagation theory in flow field, construct the propagation model of the surface of sound radiation sphere model to microphone position, and based on the influence of background noise, establish the sound propagation equation of the surface of sound radiation sphere model to microphone in hemispherical far-field noise measuring device;Sound propagation equation is converted to solve least square problem, and the sound source distribution of the surface of sound radiation sphere model is obtained, and the noise of helicopter rotor far field arbitrary position is reconstructed.Can be applied to in acoustic wind tunnel, high background noise and other complex environments reconstruct helicopter rotor sound radiation sphere, carry out practical research and application.

Provided in the present disclosure are a wind noise measurement method / apparatus / device, and a storage medium. The method comprises: for different wind speeds and different wind directions, respectively collecting signal data in a first testing environment, and sending the signal data in the first test environment to a test device, so that the test device determines the wind noise influence of wind, which has different wind speeds and different wind directions, on the audio quality of a terminal device under test; or, playing an audio test signal to a sound collection device under different wind speeds and different wind directions, so that the sound collection device respectively collects signal data in a second testing environment for different wind speeds and different wind directions. Provided in the present disclosure is a wind noise measurement method suitable for a terminal device, which method can be used for measuring the influence of wind noise on various types of terminal devices.

The application discloses a multi-measurement vector deep atom norm denoising network for line spectrum estimation and a construction method thereof, and relates to the field of signal processing. The application solves the problems of low estimation accuracy and slow convergence speed caused by a large number of iterations in the existing line spectrum estimation. The construction method of the denoising network is as follows: T, W and Lambda are selected as auxiliary variables; the auxiliary variables are used to analyze noise measurement values to obtain learning variable values, and then a reconstruction layer is established; the reconstruction layer is used to denoise the noise measurement values to obtain a denoising result, and a piecewise linear mapping function and a mapping grid are used to establish a noise estimation layer; an auxiliary layer is established according to the piecewise linear mapping function and the auxiliary variable matrix; S reconstruction layers, the noise estimation layer and the auxiliary layer are used to obtain a denoising network. A gradient-based back propagation method is used to train the denoising network to complete optimal selection of learnable parameters. The application is suitable for line spectrum estimation in radar detection, sensor array signal processing, medical imaging and communication channel estimation.

The invention describes a method (100) for reducing error in the determination of an observable of a quantum system in a quantum state on a noisy quantum computer platform, comprising the following steps: • dividing (101) an observable operator into series of base operators; • providing (102) calibration operators; • measuring (103) the calibration operators, comprising determining (104) noisy measurement results (1040) and gate-error-reduced measurement results (1050) of the calibration operators; • ascertaining (106) a calibration function (1060) for mapping the noisy measurement results (1040) to the gate-error-reduced measurement results (1050) of the calibration operators; • determining (107) noisy measurement results (1070) of the series of base operators; • determining (108) error-reduced measurement results (1080) of the series of base operators by mapping (109) the noisy measurement results (1070) by means of the calibration function (1060); • determining (110) the observable by combining the error-reduced measurement results (1080) of the series of base operators.

Using a capacitance sensor may include taking a first noise measurement by imposing a first signal on a capacitance sensor, the first signal having a first frequency; taking a second noise measurement by imposing a second signal on the capacitance sensor, the second signal having a second frequency different than the first frequency; determining the measurement with the lower amount of noise between the first noise measurement and the second noise measurement; and taking a capacitance measurement by imposing a third signal on the capacitance sensor, the third signal having either the first frequency or the second frequency based, at least in part, on the frequency of the measurement with the lower amount of noise.

The application relates to the technical field of photoelectric measurement, and discloses a mode-locked laser phase noise measurement system without dispersion management, which comprises a signal generation unit, a signal adjustment unit and a signal measurement unit. The signal generation unit comprises a mode-locked laser for generating a laser signal, a frequency doubling module connected to the output end of the mode-locked laser, and a signal extraction and screening module connected to the output end of the frequency doubling module. The signal adjustment unit is connected to the output end of the signal extraction module and comprises a signal frequency shift module and a signal extraction module connected in sequence. The signal measurement unit is connected to the output end of the signal extraction module and comprises a low-pass filter and a signal analyzer. The mode-locked laser phase noise measurement structure is newly constructed, the problem that an accurate dispersion management unit needs to be added when a traditional dual-wavelength delay self-heterodyne method is used to measure phase noise is solved, and the overall structure is simple, the measurement is accurate, and the efficiency is high.

Whistling / wheezing detection device (1) for detecting whistling / wheezing based on a sound measured from a living body while the whistling / wheezing detection device (1) is in contact with a body surface (S) of the living body, wherein the whistling / wheezing detection device (1) comprises the following: a noise measuring element (M1, M2); a space-forming element (30, 33, 34, 35, 350) that forms a recording space (SP1) which accommodates the noise measurement element (M1, M2); and a cover element (36) that forms a pressure receiving unit (3a) which closes the receiving chamber (SP1) and receives pressure from the body surface (S), wherein the space-forming element (30, 33, 34, 35, 350) has a hole section (40) that is connected to an atmosphere, the recording chamber (SP1) is connected to the atmosphere via the hole section (40), and the hole section (40) includes a branching section (BR1 to BR3) between an inlet (41) on one side of the receiving space (SP1) and an outlet (49) on one side of the atmosphere and two branched hole sections (44, 46) that branch off from one side of the inlet at the branching section (BR1 to BR3), one branched hole section (46) of the two branched hole sections (44, 46) is connected to the outlet (49) and the other branched hole section (44) of the two branched hole sections is closed.