85 results about "Attenuation ratio" patented technology

The invention discloses a tunnel monitoring method and system based on a vibrating wire sensor, and relates to the technical field of tunnel engineering construction safety monitoring, and the method comprises the steps: collecting the vibration frequency data and spatial position coordinates of the vibrating wire sensor in a monitoring region; the method comprises the following steps: calculating a time difference and an energy attenuation ratio between adjacent sensors by extracting spectrum energy density distribution, and constructing a stress wave propagation field; dividing grids in the propagation field to calculate node stress values, generating a stress field distribution cloud picture and extracting a stress concentration area; calculating a gravity center position coordinate change rate and a stress time sequence curve of the stress concentration area, and determining fracture extension parameters; and calculating a surrounding rock bearing capacity attenuation curve based on the parameters, and outputting an early warning signal when the slope exceeds a threshold value. According to the invention, real-time monitoring and early warning of the tunnel surrounding rock instability risk are realized.

The invention discloses a super capacitor energy storage life evaluation method under a fire storage frequency modulation working condition, relates to the technical field of power system energy storage, and can at least partially solve the problems that an existing super capacitor life evaluation method is poor in adaptability to the frequency modulation working condition, insufficient in multi-factor coupling quantization and lack of engineering criteria. The method comprises the steps of simulating a fire storage frequency modulation working condition and collecting multi-dimensional operation data of a super capacitor; preprocessing the collected data and extracting life characteristic parameters such as capacity attenuation rate, equivalent C rate, average temperature rise, frequency modulation load factor and the like; key influence factors are screened through correlation analysis, weight coefficients are trained through a machine learning algorithm, and a coupling influence coefficient model is constructed; establishing a capacity attenuation equation, an equivalent series resistance growth equation and a response delay growth equation, and fusing three criteria to determine a life end point; and dynamically correcting model parameters based on the real-time frequency modulation data and calculating the residual life. Accurate evaluation and dynamic prediction of the service life of the super capacitor under the fire storage frequency modulation working condition are achieved.

The invention discloses a cable partial discharge analysis method and device based on oscillatory waves. The method comprises the steps that the oscillatory waves are applied to a tested cable, and low-frequency envelopes and high-frequency pulses are synchronously collected; performing structure normalization according to cable parameters; encoding the environment and working condition data into a condition vector to implement condition normalization; carrying out domain self-adaptive alignment with an ideal template clustered according to a model, a length and a joint / terminal type, and obtaining a difference feature; constructing a PRPD joint fingerprint, and counting a pulse phase, an amplitude, an envelope attenuation rate and / or an equivalent Q; outputting defect positions, types and confidence intervals based on the difference features and the joint fingerprints; and adaptively determining multi-gear upper pressure and advanced shutdown according to the information gain, and generating maintenance priority and retest interval suggestions. Through step-by-step normalization processing, domain adaptive alignment and fusion of PRPD combined fingerprint features, diagnosis stability and reproducibility are enhanced, weak discharge and early defect detection capability are enhanced, and complex working conditions and cross-trigger adaptability are enhanced.

The invention discloses a food frying process online monitoring method and system, and relates to the technical field of food processing monitoring. The method comprises the following steps: transmitting a frequency-adjustable ultrasonic signal to a frying medium, receiving a response signal after the medium acts on food, and filtering; according to the comparison result of the amplitude attenuation rate of the response signal and the threshold value, the ultrasonic emission frequency is dynamically adjusted; performing feature extraction on the preprocessed signal to form a feature vector containing amplitude, frequency and energy features; inputting the feature vector into a judgment model trained by a dynamic frequency sample, and outputting a current frying state; and a control instruction of the frying equipment is generated so as to realize process regulation and control. Through combination of frequency-controlled ultrasonic excitation and acoustic feature extraction, the method can adapt to different grease environments and food types, gives consideration to the signal penetration depth and the signal-to-noise ratio, achieves non-destructive, real-time and quantifiable monitoring of the frying process, and remarkably improves the cooking state recognition precision and monitoring consistency.

The invention discloses a bearing performance degradation type identification method based on a vibration signal tail attenuation rate, belongs to the technical field of mechanical equipment state monitoring and fault diagnosis, and aims to improve the prediction precision of the remaining service life of a rolling bearing and improve the applicability of an intelligent prediction model by effectively identifying the bearing degradation type. The system comprises a data acquisition and preprocessing module, a tail attenuation rate calculation module, a degradation point detection module and a degradation type identification module. Firstly, feature extraction and segmentation processing are carried out on an original vibration signal of the rolling bearing; then, histogram distribution of vibration signal amplitudes is constructed, a right tail area sample is extracted, and a tail attenuation rate index representing signal extreme fluctuation attenuation behaviors is calculated through logarithmic transformation and linear fitting processing; and finally, constructing a dual judgment criterion of ratio threshold value judgment and adjacent point difference value comparison, and realizing automatic identification and classification of three typical degradation modes of bell shape, horn shape and sudden deformation.

An acoustic signal output device includes a driver unit and a housing that internally accommodates the driver unit. Here, an acoustic signal emitted from the driver unit to one side is set as a first acoustic signal, and an acoustic signal emitted from the driver unit to another side is set as a second acoustic signal. A wall portion of the housing includes a single or plurality of first sound openings for leading out the first acoustic signal to an outside and a single or plurality of second sound openings for leading out the second acoustic signal to an outside. An attenuation rate of the first acoustic signal at a second point with reference to a predetermined first point where the first acoustic signal arrives, the second point being farther from the acoustic signal output device than the first point, is equal to or less than a predetermined value smaller than an attenuation rate due to air propagation. Alternatively, an attenuation amount of the first acoustic signal at the second point with reference to the first point is equal to or more than a predetermined value larger than an attenuation amount due to air propagation.

The application discloses a partial discharge signal denoising method, comprising the following steps: building a partial discharge signal detection platform and a partial signal collection platform; measuring and detecting characteristic signals in the partial discharge signals; screening and classifying the measured signals through a Gaussian test to obtain the characteristic signals; processing and denoising the signals through a fast S transform algorithm and a singular value decomposition SVD algorithm; testing and diagnosing the denoising effect by using two coefficients of noise suppression ratio and amplitude attenuation ratio; and displaying the diagnostic analysis result on a platform display interface. The application discloses a partial discharge signal diagnostic system based on a fast S transform and an adaptive singular value, and solves the problems that the existing technical methods are difficult to balance the denoising effect and extraction speed in the characteristic extraction of the partial discharge signals and are difficult to extract the characteristics.

The invention relates to the technical field of pre-diagnosis and health management, in particular to a low-voltage switch cabinet insulation safety diagnosis method based on discharge characteristic analysis, and the method comprises the steps: synchronously collecting original optical signals through a multispectral sensor array; performing energy compensation by using a multipath reflection equivalent attenuation model to generate reconstructed spectral line intensity data; determining a virtual time zero point by using an autocorrelation function and generating virtual phase analysis atlas data; and constructing an energy spectrum gravity center space coordinate in the energy spectrum feature space to extract a gravity center red shift feature quantity. According to the method, through multi-band relative attenuation rate compensation, power frequency period statistical peak value extraction and energy spectrum space gravity center mapping, the diagnosis problem that the insulation state is difficult to quantitatively evaluate due to signal distortion, reference phase loss and fuzzy characteristic evolution in a non-line-of-sight environment is solved.

The invention provides a seismic data bidirectional frequency band expansion method based on carrier modulation, which relates to the field of seismic exploration, and comprises the following steps: processing original seismic data through time window segmentation, calculating an autocorrelation function and carrying out time domain continuation; solving a prediction coefficient based on entropy maximization constraint to generate an amplitude spectrum; calculating a boundary attenuation rate through boundary frequency point positioning; constructing an attenuation compensation function to generate a frequency domain carrier function; applying sparse constraint to solve a weighting factor and iteratively calculating a modulation amplitude spectrum; and finally, carrying out combined inverse transformation with an original phase spectrum to obtain expanded data. According to the method, the resolution and the signal-to-noise ratio of the seismic data are effectively improved, and the seismic interpretation precision is improved.

The invention relates to the technical field of semiconductor infrared temperature measurement, and provides a real-time self-calibration semiconductor infrared temperature measurement device and a control method thereof. An optical front-end unit of the device comprises a rotary driving mechanism and a rotary filter wheel located in a temperature measurement light path, and a measurement light filter, a calibration attenuation piece with a known attenuation rate and a black body reference piece are arranged on the optical front-end unit; the control unit drives the rotary filter wheel to sequentially switch the three to enter a light path; the signal processing unit converts the modulated optical signals into corresponding first, second and third voltage signals, calculates the real-time total transmittance of an optical path based on the first and second voltage signals and a known attenuation rate, compensates the third signal in combination with the first signal, and outputs a corrected temperature value according to a preset voltage-temperature mapping relation. The device is used for carrying out anti-pollution interference non-contact on-line temperature measurement on a wafer or a cavity in semiconductor manufacturing, and the detection precision and the stability and the reliability in long-term use of a semiconductor industrial site are improved.

The invention relates to the technical field of waterproof material quality detection, in particular to a waterproof roll process state measuring device and method. A surface height sequence measured through laser and contact is synchronously collected, and a surface fabric texture signal and a fabric structure compression fluctuation signal are determined; firstly, the relative displacement of the melt fabric is quantified by utilizing delay correlation between the two, so that the macroscopic process deviation caused by speed mismatch is directly identified; a nonlinear morphology residual error signal is stripped through translation correction and linear gain modeling, and the physical form of the defect is identified according to an amplitude distribution form characteristic value, so that local mutation caused by unplasticized particles and system smooth defects caused by excessive casting are effectively distinguished; the high-frequency texture attenuation rate and the linear correlation degree determined by the frequency domain transfer function are combined, and the microscopic reproduction capability of the melt is quantified to reflect the rheological state characteristics of the melt, so that single thickness detection is expanded into multi-dimensional feature decoupling diagnosis, and the accuracy of waterproof roll process state determination is improved.

The present application relates to the technical field of machining tools, and proposes a tool life real-time monitoring and early warning method and system. First, the original acoustic emission signal of the tool working site is obtained, adaptive cavitation noise cancellation processing is performed, and comparison index calculation is performed based on the processed signal, including entropy change and kurtosis calculation, frequency dispersion-attenuation coupling analysis is performed in combination with short-time Fourier transform, and frequency dispersion slope change rate and energy attenuation ratio are extracted. Subsequently, the current tool individualized threshold vector identified by the deep learning model is obtained from the cloud, compared with the comparison index, the life remaining proportion is determined, and early warning is implemented. Through millisecond acoustic emission signal analysis, microscopic secondary detection and cloud model self-learning, the present application realizes millisecond response, extremely low false alarm rate and seamless system integration under the premise of no shutdown and unattended, and breaks through the traditional fixed tool changing period, and approaches the real service life limit of the tool.

The invention provides a motor abnormal sound detection method and device, and the method comprises the steps: collecting a sound pressure signal and a rotating speed signal of the operation of a motor, carrying out the synchronous processing of the sound pressure signal and the rotating speed signal, obtaining a synchronous original signal, carrying out the feature extraction of the synchronous original signal, and obtaining a feature vector; the feature vector comprises at least one feature component of a rotating speed deviation coefficient, a frequency band energy ratio, a dominant frequency and harmonic relation index and an amplitude attenuation rate, calculating an abnormal sound risk index by using the feature vector, determining an abnormal sound judgment threshold through a dynamic threshold updating strategy, and determining the abnormal sound by comparing the abnormal sound risk index with the abnormal sound judgment threshold. And outputting a motor abnormal sound detection result. According to the motor abnormal sound detection method provided by the embodiment of the invention, the sound pressure signal and the rotating speed signal are synchronously acquired, the multi-dimensional feature vector is extracted, the abnormal sound risk index is calculated, and self-adaptive judgment is performed based on the dynamic threshold strategy, so that an automatic abnormal sound recognition process based on multi-source signal fusion is realized, and the motor abnormal sound detection efficiency is improved.

The invention discloses a main vibration source determination method of a main speed reducer and a vibration main transmission path identification method, and the method comprises the steps: setting a target point and a path point on a box body of the main speed reducer, and selecting a reference point based on the path point; excitation is applied to the path points, frequency response functions of the reference points and the target points are obtained, and the interface force of the path and the vibration response of the target points are obtained based on a TPA inverse matrix method. And analyzing to obtain a main excitation source of each target point. And calculating the relative energy attenuation rate of the path based on the distance between the transmission path and the target point. And in combination with TPA, a power flow method and a path energy relative attenuation rate, calculating to obtain the contribution degree of each transmission path, and further identifying the main transmission path of each target point. Through combination of tests, TPA, a power flow method and an energy attenuation rate, the calculation precision is improved, and vibration and noise reduction of a main speed reducer and fault diagnosis and tracing of a transmission system are facilitated.

The invention relates to the technical field of semiconductor probe performance testing, in particular to a probe performance testing method, which comprises the following steps of: calculating resistance consistency and a signal transmission fidelity ratio of a probe interference working condition through a contact simulation test and a signal transmission simulation test, and performing single-probe simulation verification; for double probes formed by qualified single probes, calculating contact pressure interference variables and electromagnetic crosstalk interference variables, and carrying out cooperative interference judgment; extracting historical probe false data, and constructing an interference false risk model and a non-interference false risk model; grouping the double probes according to interference degrees, and substituting the grouped double probes into corresponding models to calculate risk assessment values; determining an adjustment direction and an adjustment scheme for the high-risk group, and calculating the average attenuation rate of the double probes after adjustment; and after the attenuation rate is verified to reach the standard, the probe group is determined as a qualified performance test probe group, so that the accuracy, the stability and the anti-interference capability of semiconductor probe performance detection are effectively improved.

The application provides an optical fiber communication line fault feedback system and relates to the technical field of optical fiber communication fault diagnosis, which comprises a data acquisition module for collecting state parameters, a feature extraction module for extracting features of the state parameters to obtain a comprehensive feature vector, and a fault discrimination model for performing fault diagnosis based on the comprehensive feature vector, wherein the attenuation rate, reflectivity, packet loss rate, temperature, humidity, vibration signal, electromagnetic pulse signal and radio frequency interference signal of the optical fiber communication line are acquired, and the line performance vector, optical fiber fault vector, connector fault vector and interference fault vector are calculated to form the comprehensive feature vector, so that the influence of the communication related parameters and the environmental related parameters is comprehensively considered, the comprehensive evaluation of the optical fiber communication line is realized, and the precision of subsequent fault diagnosis and fault classification is improved.

The application provides a kind of early warning system and method of radial artery compression hemostat based on multiple sensors, belongs to complication early warning technical field.The method comprises the following steps: S1, multiple types of physiological signals in the radial artery compression area are synchronously collected and digitized;S2, the temperature at the proximal end and the temperature at the distal end are subjected to discrete wavelet transform;the pulse signal is subjected to time domain analysis, and the pulse amplitude is extracted;S3, a temperature distribution model of the compression area is constructed based on the temperature difference signal;S4, the resistivity distribution of the compression area is reconstructed through the electrode impedance signal, and the bleeding position is located;S5, the pressure change rate is calculated based on the pressure digital signal;the pulse amplitude attenuation rate is calculated based on the pulse amplitude;the pressure change rate, the temperature gradient vector, the pulse amplitude attenuation rate and the bleeding index are fused through a weighted summation formula, and a comprehensive risk value is obtained.The application improves the complication-related parameter coverage rate through multiple sensors, and improves the timeliness and accuracy of complication early warning.

The invention discloses a single-power wide common-mode input current detection amplification circuit, and the circuit comprises a pre-attenuation resistance network which is used for attenuating a common-mode voltage on a differential signal according to a preset attenuation ratio K, and then inputting the attenuated common-mode voltage to an input end of a first operational amplifier; the first operational amplification module is used for amplifying the signal output by the front attenuation resistance network by G1 times and then outputting the amplified signal in a differential form; and the second operational amplification module is used for converting the differential output of the first operational amplification module into a single-ended output signal and providing G2 times of gain. According to the single-power-supply wide-common-mode-input current detection amplifying circuit, common-mode input voltage far exceeding working voltage can be input, and the application range of a current detection amplifier is widened to a great extent.

An acoustic signal output device includes a concave reflector with a surface configured as a rotational paraboloid or an approximation thereof, and a first driver unit positioned within the reflector. The reflector has a cutout portion at a part of its open end, providing an aperture to the exterior. The first driver unit emits a first acoustic signal in a first direction and a second acoustic signal in a second, opposing direction. The device is configured such that the attenuation rate of the first acoustic signal between a predetermined first point of arrival and a more distant second point is less than or equal to a predetermined value that is smaller than the attenuation rate due to air propagation alone between the same two points.

The application discloses a UAV-mechanical dog cooperative multi-frequency sound wave ore heap hollow monitoring system and method, and relates to the field of ore heap hollow monitoring. The system comprises the following steps: a plurality of receiving sensors are uniformly arranged on the surface of the ore heap in the stoping space; a UAV platform and a mechanical dog are arranged in the stoping space; a multi-sensor integrated unit comprises a sound wave emission module, an RTK real-time dynamic positioning module, a laser radar module and a visual SLAM module; and a computing and analyzing terminal is connected with the mechanical dog, the multi-sensor integrated unit and the plurality of receiving sensors. The method comprises the following steps: after each ore drawing operation is completed, the mechanical dog is used to arrange a plurality of receiving sensors on the surface of the ore heap at the bottom of the stoping space in the form of a diamond grid; the UAV platform is controlled to sequentially traverse the arrangement points of the receiving sensors, and sound wave signals are emitted; the first wave arrival time, the amplitude attenuation rate and the spectral barycenter offset are obtained through the receiving sensors; and three-level early warning is carried out. The system and method can efficiently and accurately monitor the hollow condition of the ore heap.

The invention discloses a power transmission line broken strand monitoring method and device, and relates to the technical field of power transmission line broken strand monitoring. Monitoring data of a power transmission line are obtained through preset anti-vibration broken strand monitoring equipment, broken strand feature extraction is carried out on the monitoring data, and the corresponding amplitude attenuation rate, the corresponding signal-to-noise ratio and the corresponding vibration total energy are obtained; performing frequency spectrum distortion evaluation on the total vibration energy according to a preset reference vibration energy threshold value to obtain a corresponding frequency spectrum distortion coefficient, performing threshold value setting on the reference vibration energy threshold value and a preset reference ultrasonic attenuation threshold value based on a signal-to-noise ratio to obtain a corresponding vibration energy threshold value and a corresponding ultrasonic attenuation threshold value, according to the vibration energy threshold value, the frequency spectrum distortion coefficient, the ultrasonic attenuation threshold value, the amplitude attenuation rate and the vibration total energy, strand breakage detection is carried out, and a corresponding detection result is obtained. The problems that traditional power transmission line broken strand monitoring mostly depends on manual inspection, the efficiency is low, the cost is high, early warning and accurate diagnosis of hidden danger of broken strands are difficult to achieve, and the running reliability of a power transmission line is reduced are solved.

The application relates to the technical field of monitoring and early warning, and discloses an online monitoring and early warning system for intelligent traffic engineering construction, which comprises the following steps: firstly, a single-frame image of a road construction early warning area is acquired, the single-frame image is converted into a developed image of a road plane by using camera calibration parameters, and a long-strip work belt area covering a near-distance sub-area and a far-distance sub-area is calibrated in the image; a two-dimensional Fourier transform is performed on the area to obtain a frequency domain amplitude spectrum; a first sector and a second sector are divided according to a road driving direction; and the direction energy in a medium spatial frequency range is calculated respectively. Further, the road image definition change is analyzed through the energy ratio and the attenuation rate; grade determination is carried out according to a preset threshold value; a visual grade output of a monitoring picture is generated; and intelligent visual monitoring and real-time early warning of the construction area under complex illumination and meteorological conditions are realized.

The application relates to the technical field of communication interference elimination, in particular to a pulse interference elimination method for a power carrier communication chip, which comprises the following steps: acquiring carrier signals of each communication node in a power carrier communication network and the length of a power line between any two communication nodes; acquiring suspected pulse noise points; calculating pulse noise weights of the suspected pulse noise points; intercepting each suspected pulse signal in the carrier signal; obtaining a pulse noise spectrum diagram of each communication node; calculating line loss ratios between any two communication nodes; obtaining a comprehensive pulse spectrum diagram of each communication node; calculating an attenuation ratio of each frequency position; obtaining a noise suppression spectrum diagram; and obtaining a carrier signal after noise suppression based on the noise suppression spectrum diagram, so as to eliminate pulse interference in the carrier signal. The application dynamically filters the frequency domain characteristics of the carrier signal, and improves the communication quality of the power carrier communication chip.

[Problem] To provide a technology capable of suppressing sound leakage to the outside of a room even when a user listens to audio in the room at a preferred sound volume. [Solution] This multi-channel audio device 1 performs sound output on audio playback signals from channels through respective playback speakers 2, and performs sound output on antiphase signals of the audio playback signals through an antiphase speaker 3. The attenuation rates and the delay times of the audio playback signals output from the respective playback speakers 2 at the installation position of the antiphase speaker 3 are stored in advance, and during the audio playback, the antiphase signals of the audio playback signals of the respective channels are attenuated on the basis of the respective attenuation rates, are delayed on the basis of the respective delay times, and are output as sound from the antiphase speaker 3.

The application provides a microwave link raindrop spectrum measurement method based on an optimal estimation method, comprising the following steps: establishing prior information based on historical observation data of a raindrop spectrometer; establishing a forward model based on multiple microwave links; extracting rain-induced attenuation rates based on the multiple microwave links; establishing an observation vector according to the rain-induced attenuation rates; and performing optimal estimation on a to-be-measured raindrop spectrum function based on the observation vector, the forward model and the prior information, and calculating a raindrop spectrum function optimal value and a raindrop spectrum function uncertainty. The application solves the problems of inaccurate measurement and high cost of large-scale near-ground raindrop spectrum information measurement in the prior art.

This electromagnetic wave absorbing member for a sub-terahertz band is characterized by comprising a polymer material and carbon nanotubes, the carbon nanotubes including single-walled carbon nanotubes as a main component, the electrical conductivity of the electromagnetic wave absorbing member being 0.1 (S / cm) to 2.0 (S / cm), and the attenuation rate at a frequency of 300 (GHz) being 5 (dB) or more.

The present application relates to motor manufacturing process technical field, more specifically, it relates to a kind of high torsion multi-stage series motor and structural stability detection process, including the modal response of the axial and radial of the frame of high torsion multi-stage series motor is collected, axial main frequency, axial damping ratio and the phase difference of radial two test points are calculated, and compared with preset threshold value;Continuous sweep frequency sinusoidal excitation is applied to motor frame, the nonlinear index of each frequency point is calculated and compared with preset threshold value, while detecting whether resonance peak is split;Then short-time half-sine pulse impact is applied to motor frame, free decay vibration signal is collected, and attenuation main frequency, logarithmic attenuation rate and cross-correlation peak delay are extracted from the time domain of free decay vibration signal, the pretightening force and connection stiffness index of two connecting points are back calculated, finally ensure that high torsion multi-stage series motor can meet the requirement of structural stability when leaving factory, and can be closed-loop corrected by detection Parameter of assembly process.

The invention belongs to the technical field of power cable monitoring, and discloses a power cable head end anti-radio frequency domain suppression method and device based on dynamic mode decomposition, a computer storage medium and electronic equipment, and the method comprises the steps: obtaining a cable frequency domain head end reflection coefficient spectrum reflection signal, and carrying out the preprocessing to obtain a signal; constructing a spatio-temporal data matrix and a corresponding time migration matrix according to the signals, and performing dynamic mode decomposition and reconstruction; and calculating the frequency and attenuation rate of each reconstruction mode, screening the reconstruction modes, and reconstructing the interference-removed signal according to the screened modes. According to the method, the dynamic mode can be adaptively extracted, the head end reflection interference is effectively separated and eliminated, and the defect is accurately positioned.

The application discloses a motor bearing online fault diagnosis method based on edge calculation and relates to the technical field of fault diagnosis, which comprises the following steps: acquiring first frequency information and second frequency information of a processing device; determining an attenuation ratio feature; adjusting a cutoff frequency parameter of a filter module based on the attenuation ratio feature; acquiring corresponding cutoff band information of the filter module under the adjusted cutoff frequency parameter, and determining compensation energy information based on preset reference envelope features and the cutoff band information; acquiring vibration feature information processed by the filter module, and determining dynamic baseline information based on the vibration feature information and the compensation energy information; and performing fault diagnosis on a target device based on the dynamic baseline information; and performing fault diagnosis on a target motor bearing based on a dynamic alarm baseline; and the application improves the accuracy and reliability of motor bearing online fault diagnosis.

The application belongs to the field of blood viscosity monitoring, and provides a resonance-based non-invasive blood viscosity monitoring method and system. The method comprises determining corresponding resonance frequency and resonance incidence angle; the signal wave of the resonance frequency is incident to the target blood vessel region of the current individual at the resonance incidence angle each time the measurement is performed, and the signal wave characteristic parameter at each time of measurement is extracted; the signal wave characteristic parameter comprises the propagation speed of the signal wave in the blood, the attenuation rate of the signal wave, the change of the phase of the signal wave, and the reflection intensity of the signal wave; the change direction of the blood viscosity in single detection is inferred according to the change of the propagation speed of the signal wave in the blood in the single detection process; and the blood viscosity value in single detection is obtained based on all the signal wave characteristic parameters in the single detection process and the relationship model of the signal wave characteristic parameters and the blood viscosity which is constructed in advance.