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120 results about "Nonlinear parameters" patented technology

Ultrasonic nonlinear static parameter monitoring method for creep damage of high-temperature alloy component

The invention provides an ultrasonic nonlinear static parameter monitoring method for creep damage of a high-temperature alloy component, and particularly relates to the technical field of material monitoring. The method comprises the following steps: S1, arranging an ultrasonic probe; s2, determining the emission frequency of the excitation end; s3, respectively calculating an incident angle and an emergent angle of the signal; s4, exciting fundamental frequency ultrasonic waves; s5, receiving the signal and uploading the collected signal to a cloud processing system; s6, carrying out fast Fourier transform and calculating a nonlinear parameter of a static component; s7, establishing a linear relation with creep time, and constructing a creep damage linear quantitative model; s8, calculating a static component nonlinear parameter of the healthy sample; and S9, completing quantitative analysis of the damage by using nonlinear parameters. The method solves the problems that a traditional nonlinear ultrasonic method depends on second harmonic nonlinear parameters, phase velocity matching conditions in the middle and later periods are seriously damaged, response shows a nonlinear trend, unique creep time cannot be determined according to the parameters, and then the unique damage state cannot be determined.
Owner:EAST CHINA UNIV OF SCI & TECH

5G radio frequency signal amplification method and system

The invention relates to the technical field of radio-frequency signal processing, and discloses a 5G radio-frequency signal amplification method and system, and the method comprises the steps: decomposing an obtained radio-frequency signal into a high-frequency sub-band and a low-frequency sub-band through a multilayer wavelet packet, judging whether the radio-frequency signal is sparse in a wavelet packet domain, and carrying out the sparse reconstruction of an LI norm minimization problem if the radio-frequency signal is sparse; obtaining feature data of each sub-band, extracting a nonlinear transfer function of each sub-band through a CNN-GRU network, and carrying out transfer learning pre-training and dynamic adaptation updating; on the basis of dynamic adaptation update ending, layered memory polynomial calculation and layered model joint output construction, layered model parameter optimization is converted into a least square problem to obtain an error compensation function, and resource allocation is dynamically adjusted according to the peak-to-average power ratio of an input signal; and based on power amplifier state data, holographic sensing is performed on nonlinear parameters of the device through a fusion model, and dynamic changes of the device are compensated through multi-stage calibration and calibration delay is controlled.
Owner:SHANGHAI DAQI INFORMATION TECH CO LTD

Agent-free ISP hyper-parameter high-speed optimization method and system

The invention relates to the technical field of image signal processing, and discloses an agent-free ISP hyper-parameter high-speed optimization method and system, and the method comprises the following steps: collecting RAW data through a sensor, carrying out the black level correction, and initializing the ISP register parameter mapping; a multi-dimensional state vector is constructed by combining the coded image and the parameters, and the master and slave agents generate discrete adjustment amounts in parallel; after a register is updated through nonlinear quantization, a composite reward is calculated based on target detection and image quality, and data is stored and network parameters are updated through a priority experience pool; the system comprises a sensor module, an ISP hardware processing unit, a master-slave agent decision module, a reward calculation module, a register mapping module and an experience playback module. According to the method, hardware-in-the-loop and deep reinforcement learning are combined, and the problems of proxy model distortion, response lag, high data dependence and parameter mutation are solved through master-slave agent parallel decision, a self-supervision reward mechanism and nonlinear parameter mapping.
Owner:上海芯开技术有限公司

Proportioning optimization method of nano-composite flame-retardant master batch in engineering plastic based on machine learning

PendingCN121885018APrecise ratioEfficient proportioning and adaptive optimizationBiological modelsChemical machine learningEngineering plasticThe Internet
The invention belongs to the technical field of crossing of high polymer materials and artificial intelligence, and discloses a method for optimizing the proportion of a nano-composite flame-retardant master batch in engineering plastic based on machine learning. The method is used for solving the problems that a traditional experience trial and error method is low in efficiency in multi-target performance collaborative optimization, high-dimensional nonlinear parameter space search is difficult, and microscopic coupling effect modeling is missing. According to the method, a multi-dimensional input feature set containing material composition and process parameters is constructed, six key performance indexes are combined to form training data, a mixed model formed by cascading a multi-layer perceptron and Gaussian process regression is trained, an improved non-dominated sorting genetic algorithm (NSGA-II) is adopted for multi-target global optimization, and an optimal ratio meeting preset constraints is obtained. The method is an industrial internet technology system service, and solves the technical problem that multi-target performance is difficult to collaboratively optimize due to the fact that a traditional experience trial-and-error method cannot perform modeling and searching on a high-dimensional nonlinear parameter space of a nano-composite flame-retardant system.
Owner:LIAONING WEIKETRUI FLAME RETARDANT MATERIAL TECH CO LTD

Ultrasonic nonlinear parameter imaging method and system, medium and program product

The invention belongs to the technical field of ultrasonic imaging, and particularly relates to an ultrasonic nonlinear parameter imaging method and system, a medium and a program product. The method comprises the following steps: calculating a fundamental signal and a harmonic signal based on an ultrasonic echo RF signal; extracting the amplitude of the fundamental wave signal and the amplitude of the harmonic wave signal, and calculating to obtain a fundamental wave amplitude ratio and a harmonic wave amplitude ratio; calculating an initial value of a nonlinear coefficient according to a ratio of the fundamental wave amplitude ratio to the harmonic wave amplitude ratio, and estimating a value range of the nonlinear coefficient by using a Newton iteration method; and generating an ultrasonic image based on the value range of the nonlinear coefficient. In the ultrasonic non-linear parameter imaging process, a method for solving a non-linear coefficient by adopting a Newton iteration method is further disclosed, so that the dynamic range of the estimated non-linear coefficient value is expanded, the distinguishing between normal tissues and focus tissues in an obtained ultrasonic image is more obvious, and the sensitivity is higher.
Owner:SASET CHENGDU TECH LTD

Method for imaging tiny foreign matters in soft package battery based on nonlinear ultrasound

The invention discloses a non-linear ultrasound-based soft package battery internal tiny foreign matter imaging method, which belongs to the field of power battery manufacturing, and comprises the following steps: exciting and receiving non-linear ultrasound on the surface of a soft package battery by using a non-linear ultrasound measurement system, and extracting a non-linear ultrasound time domain signal carrying foreign matter information; performing C scanning on the soft package battery by adopting a three-degree-of-freedom motion platform, and obtaining acoustic nonlinear parameters and spatial distribution of the acoustic nonlinear parameters based on the position of a focused ultrasonic transducer, the nonlinear ultrasonic time domain signal and the frequency spectrum; performing normalization processing on the acoustic nonlinear parameters, and constructing a function relationship between the normalized acoustic nonlinear parameters and different foreign matters; and inverting the size and the position of the foreign matter based on the function relationship between the normalized acoustic nonlinear parameter and different foreign matters and the spatial distribution of the acoustic nonlinear parameter.
Owner:UNIV OF SHANGHAI FOR SCI & TECH

Signaling of information for non-linearity model

Aspects relate to signaling relating to a non-linearity model for power amplifier circuitry of a transmitting device. The power amplifier circuitry may apply digital pre-distortion (DPD) to a signal prior to amplification and transmission of the signal. A receiving device may apply digital post-distortion (DPoD) to a signal received from the transmitting device where the DPoD is based on the non-linearity model. The transmitting device may send to the receiving device non-linearity parameters for the non-linearity model.
Owner:QUALCOMM INC

Direct current furnace turbine-furnace coordination system dynamic modeling method suitable for wet condition

The invention relates to a direct current furnace machine-furnace coordination system dynamic modeling method suitable for a wet condition. Based on the law of mass conservation and energy conservation, a lumped parameter method is adopted to construct a dynamic model comprising a coal pulverizing system, a coal economizer-water wall system, a water storage tank system, a superheater system and a steam turbine system; identifying parameters are optimized step by step by only utilizing unit variable load dynamic operation data and combining with the mechanism constraint that the heat absorption capacity of a working medium is monotonically increased along with the coal quantity as fired: static parameters are determined through dynamic data regression, nonlinear parameters are optimized based on a preset water-cooled wall outlet flow and dryness function structure, and the heat absorption capacity of the working medium is calculated. And finally, identifying dynamic parameters step by step by adopting an immune genetic algorithm. The dynamic characteristics and the physical consistency of the established model are verified through open-loop simulation, and the technical problems that dynamic description of the water level of the water storage tank is missing and the modeling precision is low under the wet working condition are solved.
Owner:GUODIAN SCI & TECH RES INST +1

Sine frequency modulation harmonic error compensation method based on Bessel function modulation characteristics

The invention discloses a sine frequency modulation harmonic error compensation method based on Bessel function modulation characteristics, and relates to the technical field of sine frequency modulation nonlinear parameter compensation and high-precision measurement of target absolute distance based on multi-wavelength interference. The problem that the constant phase demodulation precision is insufficient due to the fact that carrier harmonic waves, accompanying amplitude modulation and modulation depth errors cannot be effectively suppressed due to laser modulation nonlinearity in existing sine frequency modulation distance measurement is solved. According to the method, after sine frequency modulation interference signals are collected, high-pass filtering is carried out to remove low-frequency components, Hilbert transform is carried out to remove envelope suppression associated amplitude modulation, window function frequency mixing is carried out to extract modulation depth, a matched carrier containing second harmonics is constructed, and frequency modulation harmonic parameter optimization is achieved through baseband amplitude maximization. And finally, carrying out orthogonal demodulation on the compensated interference signal to obtain a high-precision constant phase. The method is suitable for high-precision multi-wavelength interference ranging, precision displacement measurement and optical metering systems.
Owner:HARBIN INST OF TECH +1

Gap nonlinear control surface flutter wind tunnel test system and method based on steering engine excitation

The invention provides a gap nonlinear control surface flutter wind tunnel test system and method based on steering engine excitation. The system comprises a wind tunnel test section, a test object and a parameter-adjustable excitation mechanism outside a wind tunnel field, wherein the parameter-adjustable excitation mechanism is composed of a transverse clamping mechanism, a longitudinal supporting mechanism, an excitation system and an angle sensor. The excitation system comprises a steering engine, a steering engine rocker arm and a connecting rod, one end of a spring rod is fixed to the longitudinal supporting mechanism, and the other end is in clearance fit with the connecting rod. By adjusting the effective length of the spring rod, the fit clearance and the excitation of the steering engine, the clearance nonlinear rigidity applied to the test control surface can be changed. In a wind tunnel test, an angle sensor is used for collecting rudder shaft rotation angular displacement response in real time, excitation-response characteristic testing before and after flutter occurs is achieved, and the influence rule of gap nonlinear parameters on rudder surface dynamic characteristics is effectively studied. The test principle is simple, and a new way is provided for excitation-response characteristic measurement of the full-motion control surface under different gap nonlinear rigidities.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Method for predicting storage life of composite material based on variable transformation and genetic algorithm

The invention discloses a composite material storage life prediction method based on variable transformation and a genetic algorithm, and relates to the technical field of composite material performance evaluation and life prediction, and the method comprises the steps: obtaining performance degradation data at different temperatures through an accelerated aging test, and building a semi-empirical performance degradation model; specific variable transformation is introduced, a nonlinear optimization problem is converted into a linear regression problem, partial model parameters are rapidly solved by adopting a least square method, and meanwhile, key nonlinear parameters are globally optimized by using a genetic algorithm, so that the defect that a traditional method is easy to fall into local optimum is overcome. And establishing a temperature-service life relationship by combining with an archenius model, and realizing storage life prediction at normal temperature. The method also integrates sensitivity analysis and uncertainty quantification functions, and provides reliability evaluation for a prediction result. The method fully considers the influence of the environment temperature, meets the requirement of efficient prediction, and improves the precision and stability of life prediction.
Owner:ROCKET FORCE UNIV OF ENG

Nanoscale displacement real-time compensation measurement method and system based on dual-frequency laser interference

The invention discloses a nano-scale displacement real-time compensation measurement method and system based on double-frequency laser interference, and belongs to the technical field of precision measurement. In order to solve the problems that three error sources of environmental drift, periodic nonlinear error and dynamic vibration are mutually coupled and have high real-time requirements in dual-frequency laser interference measurement, a multi-source error unified state space model including measured displacement, an air refractive index parameter, a nonlinear error parameter and a vibration disturbance quantity is constructed. A high-dimensional state vector is divided into a displacement-refractive index group and a nonlinear parameter group by adopting an extended Kalman filter of a grouping updating strategy, the displacement-refractive index group and the nonlinear parameter group are alternately updated in an assembly line parallel mode, nonlinear parameters are identified in real time in combination with an online recursive least square algorithm, and the state of the filter is corrected through a state coupling injection mechanism. Real-time compensation with the end-to-end delay smaller than 80 microseconds is achieved, the displacement measurement residual error is controlled within + / -0.3 nm under the composite disturbance condition, and the method is suitable for precise assembly of intelligent glasses optical assemblies.
Owner:ROBO (SHANGHAI) TECH CO LTD

Phase-control multichannel nonlinear ultrasonic nondestructive testing system and method based on phase reversal excitation

The invention discloses a phase-control multi-channel nonlinear ultrasonic nondestructive testing system and method based on phase reversal excitation, and the method comprises the steps: generating multi-channel phase reversal waveform data and a control instruction by an upper computer, carrying out the nonlinear parameter extraction of a received digital signal, and calculating a nondestructive testing result; the phase-control high-energy fundamental frequency ultrasonic excitation module suppresses a fundamental frequency signal for the electric signal with the phase reversal waveform, enhances the harmonic amplitude, and performs delay excitation to realize fixed-point focusing; the transmitting transducer array and the receiving transducer array convert the electric signal and the acoustic signal; the multi-path double-band-pass filter is used for carrying out fundamental wave suppression, harmonic wave enhancement and clutter filtering to enhance a nonlinear effect and improve a signal-to-noise ratio; and the phase-controlled ultrasonic acquisition module is used for filtering, amplifying and sampling the multi-channel feedback electric signal and converting the multi-channel feedback electric signal into a digital signal. The method has the multi-channel nonlinear ultrasonic evaluation capability, can realize multi-channel phase reversal waveform excitation, has the ultrasonic fixed-point focusing capability, and remarkably improves the nonlinear effect detection result, so that the detection result is more accurate.
Owner:FUDAN UNIVERSITY +1

Model parameter estimation device and model parameter estimation method

This model parameter estimation device comprises a state quantity calculator to calculate state quantities indicating a state of a target system with respect to a measured value of an input on the basis of a state equation obtained by assigning values to nonlinear parameters for a model that represents the target system using the nonlinear parameters and linear parameters, and time-series data of the input and an output of the target system, a linear parameter estimator to estimate the linear parameters that minimize an error between the measured value of the output and an estimated value of the output calculated on the basis of the model, the state quantities, and the measured value of the input, and a nonlinear parameter updater to repeatedly update the values of the nonlinear parameters so as to make the minimized error to be small until a convergence condition is satisfied.
Owner:MITSUBISHI ELECTRIC CORP

A method and device for measuring nonlinearity of an electro-optical modulator

The present invention discloses a method and device for measuring the nonlinearity of an electro-optical modulator, belonging to the technical field of photoelectric device measurement, and includes the following steps: inputting an optical signal output by a laser source into an electro-optical modulator to be measured; the optical signal passes through an electro-optical modulator to be measured, and outputs a modulated optical signal; the modulated optical signal enters a standard photodetector operating in a linear region, and a large-signal response item of the electro-optical modulator to be measured is obtained at different input electrical signal powers; an electrical signal is output to the electrical signal output end of the electro-optical modulator to be measured via a small-signal disturbance source, and a small-signal response item of the electro-optical modulator to be measured is obtained at different input electrical signal powers. By combining the large-signal response item and the small-signal response item, the complete nonlinear parameters of the electro-optical modulator to be measured at the input electrical signal power are obtained; and further, the complete nonlinear parameters of the electro-optical modulator to be measured at different frequencies are obtained. The present invention can achieve high-precision measurement of the nonlinearity of electro-optical modulators.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

An ultrasound nonlinear parametric imaging method, system, medium, and program product

This invention belongs to the field of ultrasound imaging technology, specifically relating to an ultrasound nonlinear parameter imaging method, system, medium, and program product. The method includes: calculating a fundamental wave signal and harmonic signals based on ultrasound echo RF signals; extracting the amplitudes of the fundamental wave signal and the harmonic signals, and calculating the fundamental wave amplitude ratio and harmonic amplitude ratio; calculating an initial value of the nonlinear coefficient based on the ratio between the fundamental wave amplitude ratio and the harmonic amplitude ratio, and estimating the range of values ​​for the nonlinear coefficient using Newton's iteration method; and generating an ultrasound image based on the range of values ​​for the nonlinear coefficient. In the process of ultrasound nonlinear parameter imaging, a method for solving the nonlinear coefficient using Newton's iteration method is further disclosed, thereby expanding the dynamic range of the estimated nonlinear coefficient values, resulting in a clearer distinction between normal tissue and lesion tissue in the obtained ultrasound image, and higher sensitivity.
Owner:SASET CHENGDU TECH LTD

Method for influencing acoustic parameters by dislocation dipole defects in aluminum matrix

The invention relates to a method for influence of dislocation dipole defects in an aluminum matrix on acoustic parameters, belongs to the technical field of discrete solution, and provides a novel molecular dynamics simulation method for researching ultrasonic sound velocity, sound attenuation and acoustic nonlinear parameter change on the basis of two dislocation dipole structures. The method specifically comprises the following steps: controlling the type and the number of dislocation dipoles in an aluminum matrix, carrying out atomic scale acoustic simulation on dislocation dipole models of different types and numbers by adopting a phase inversion technology, extracting sound velocity by adopting a cross correlation method, extracting sound attenuation by adopting a Hilbert transformation method and extracting acoustic nonlinear parameters by adopting an FFT method aiming at four-phase signals; and precise extraction of acoustic parameters is realized. And determining the contribution of the dislocation defect to the acoustic parameters based on the relationship fitting of the three acoustic parameters and the dislocation defect, thereby realizing the prediction from the acoustic parameters to defect characteristics.
Owner:ZHONGBEI UNIV

Digital predistortion method for improving linearity of power amplifier in phased array system

The application relates to the technical field of wireless communication, and discloses a digital predistortion method for improving the linearity of a power amplifier in a phased array system, which comprises the following steps: step one, acquiring nonlinear parameters of a power amplifier under dynamic load in real time, wherein the nonlinear parameters comprise input signal amplitude and phase characteristics, temperature parameters and quantum tunneling current parameters; step two, generating a predistortion compensation signal based on the nonlinear parameters, wherein the predistortion compensation signal comprises a quantum phase compensation term and a dynamic phase change compensation term; and step three, superimposing the predistortion compensation signal to an original input signal to generate a predistortion modulation signal. The application improves the linearity of the power amplifier by introducing the quantum phase compensation term and the dynamic phase change compensation term, and improves the accuracy of predistortion compensation by accurately acquiring the nonlinear parameters in real time under the dynamic load environment.
Owner:SHANGHAI JINGJI COMM TECH CO LTD

Semi-parameter clustering method for screening scrapped lithium ion batteries in electric vehicles

The invention provides a semi-parameter clustering method for screening scrapped lithium ion batteries in electric vehicles, and relates to the technical field of roadbed stability evaluation in seasonal frozen soil regions. Linear parameters, including voltage change data, internal resistance change data and nonlinear parameters, of the batteries in charge and discharge cycles are collected; comprising a discharge curve and temperature change data, and dominant trend and recessive complex characteristics of battery performance are comprehensively obtained; secondly, regression fitting is adopted for linear parameters to extract degradation trend feature data, semi-parameter modeling is adopted for nonlinear parameters to extract complex feature data, and the degradation trend feature data and the complex feature data are combined to form comprehensive feature data; and finally, based on the comprehensive feature data, establishing a clustering model cooperatively by using K-Means + + and DBSCAN algorithms, and accurately classifying the batteries into normal batteries, degraded batteries and scrapped batteries by processing the problems of non-uniform data distribution, fuzzy category boundary and the like.
Owner:ANHUI UNIV

A bearing stress state measurement method based on resonance attenuation method and related device

The application discloses a bearing stress state measurement method based on a resonance attenuation method and related devices, and the bearing-main shaft system is loaded in the mode of electromagnetic loading. The resonance attenuation method in the nonlinear parameter identification method is used to obtain an attenuation response curve, and the instantaneous frequency and envelope amplitude are obtained based on a transient time-frequency signal analysis method, and then the main curve is identified from the measured bearing-main shaft system. A quasi-static model of the bearing is established to obtain the mapping relationship between the bearing stress state and the nonlinear non-time-varying stiffness, and the external loading state of the bearing is effectively and accurately detected through multiple tests on the nonlinear stiffness of the bearing system in the actual operation process. The application is suitable for multiple types of assembled angular contact ball bearings and is suitable for accurate measurement of the bearing stress state.
Owner:XI AN JIAOTONG UNIV

A method for identifying non-linear parameters of structural clearances

ActiveCN115730517Bsimple processPhysical concepts are clearSustainable transportationBiological modelsMathematical modelLinear Parameter Identification
The present invention discloses a method for identifying nonlinear parameters of structural clearances. First, a mathematical model of the structural clearance nonlinear system is established; then, the frequency response function of the system under sinusoidal sweep excitation is obtained through the input-output response of the system; in the frequency response function, a pair of symmetric displacement points exist at any displacement response amplitude to define the same displacement frequency response function. By defining the real and imaginary parts of the displacement frequency response function through the symmetric displacement FRF points at each given displacement response amplitude, the natural frequency of the system related to the displacement response amplitude can be obtained; then, the expression of the nonlinear equivalent stiffness of the system is extracted through the simulation analysis of the model, and the equivalent stiffness curve of the system is further obtained through the model simulation data; finally, based on the particle swarm algorithm, the clearance characteristic parameters are obtained by curve fitting according to the equivalent stiffness expression obtained by integration and the equivalent stiffness curve obtained by model simulation; the present invention can identify the clearance nonlinear parameters more quickly and accurately globally.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

A method for monitoring the state of a resonant capacitor of a medium voltage direct current LLC resonant converter

The method for monitoring the resonant capacitor state of the medium-voltage direct-current LLC resonant converter comprises the following steps: closing the switch tube S 11 ~S 41 of the full-bridge at the initial moment when the LLC resonant converter is stopped, then turning on the switch tube S 31 and S 41 after the closing process lasts for 500 ns, forming a discharge loop of a resonant cavity independent of the latter stage, then collecting the time sequence data of the resonant current in the resonant cavity, and estimating the resonant capacitor by using a nonlinear parameter identification algorithm, wherein the estimation is sequentially performed by encoding, initializing the population, calculating the individual fitness, selecting the cross variation evolution, and iterative optimization, finally searching for the optimal resonant current estimation value, and calculating the resonant capacitor estimation value based on the corresponding resonant frequency and resonant inductance. The present application estimates the resonant capacitor value based on the discharge curve of the limited sampling data, has low cost and high reliability, and the present application estimates the parameters by using the nonlinear parameter identification algorithm, and has high estimation accuracy.
Owner:HUNAN UNIV

Nonlinear parameter measurement method and device of photoelectric device, electronic equipment and medium

The invention provides a nonlinear parameter measurement method and device of a photoelectric device, electronic equipment and a medium, and relates to the technical field of metering of photoelectric devices. At least one group of a first light source and a second light source is obtained; obtaining mixed emergent light; controlling the tested photoelectric device to capture the mixed emergent light, and converting the mixed emergent light into an electric signal; collecting a characteristic signal point set; and on the basis of the characteristic signal point set, obtaining a nonlinear parameter of the tested photoelectric device. According to the invention, automatic and rapid measurement of nonlinear parameters of the photoelectric device is realized. By regulating and controlling the peak wavelength, the bandwidth, the optical power, the pulse frequency, the duty ratio and the amplitude of the first incident light and the second incident light, the influence of factors such as light source mismatching and power drift of the light source on nonlinear parameter measurement is reduced, and the efficiency and the accuracy of nonlinear parameter measurement of the photoelectric device are improved. Meanwhile, non-linear spectrum dependence characterization and wide dynamic range characterization spanning multiple orders of magnitude are also realized.
Owner:NATIONAL INSTITUTE OF METROLOGY CHINA

A pre-equalization compensation method for terminals with known transmitter IQI and nonlinear parameters in a TDD-OFDM direct conversion system.

This invention discloses a pre-equalization compensation method for a terminal in a TDD-OFDM direct conversion system with known transmitter IQI and nonlinear parameters. The method includes: the base station cyclically sending P different training sequences to the terminal; the terminal using a sliding window least squares-based channel state information tracking algorithm to track and estimate the channel state information, where δ is a threshold representing the correlation of the channel within adjacent symbol periods; and pre-equalization compensation performed directly at the terminal. Using the pre-equalization compensation algorithm, a modified data sequence can be obtained and sent to the base station. This invention considers three factors in wireless communication systems: I-path and Q-path imbalance caused by the non-ideal nature of analog components in RF transceivers, power amplifier nonlinearity, and multipath channels. It enables distributed processing within the cell, effectively reducing the demodulation burden on the base station and has wider applicability than traditional compensation methods.
Owner:JIANGSU UNIV OF SCI & TECH

Backstepping sliding mode control method for heavy-duty forklift pump-controlled lifting system and based on non-linear observer

The present invention relates to the technical field of electro-hydraulic servo control. Provided is a backstepping sliding mode control method for a heavy-duty forklift pump-controlled lifting system and based on a non-linear observer. In the method, a non-linear robust sliding mode position servo controller with disturbance compensation is designed on the basis of the idea of a backstepping method. Aiming at the problem of the difficulty of controlling the precision of a heavy-duty forklift pump-controlled lifting position, the present invention realizes precise load observation, takes non-linearity and parameter uncertainty into consideration, and uses a sliding mode term to address non-linearity and uncertainty, thereby reducing the effects of abrupt load changes, external disturbance, and unmodeled dynamics on control precision, and achieving a high-precision tracking performance.
Owner:HUAQIAO UNIVERSITY

Parameter regulation and control method and device for nonlinear vibration absorber of thin-wall component

The invention discloses a parameter regulation and control method for a nonlinear vibration absorber of a thin-wall component, which comprises the following steps of: acquiring signal data of a piezoelectric module under the control of an external acting force of a piezoelectric plate for driving a thin-wall component plate module and the piezoelectric module; based on the bias input voltage, the signal data sequentially passes through the circuit module and the control module to obtain the control input voltage and the control output voltage of the control module and the bias output voltage of the circuit module; based on the signal data and the external acting force, parameters of an equivalent circuit are obtained through the thin-wall structure dynamic model and the control model, and the parameters of the equivalent circuit are used for regulating and controlling parameters of the nonlinear vibration absorber; and based on the signal data, the control input voltage, the control output voltage, the bias input voltage and the bias output voltage, linear parameters and nonlinear parameters of the control module are obtained, so that the nonlinear parameters are matched with capacitance parameters in the parameters of the equivalent circuit, and the linear parameters are matched with inductance parameters and resistance parameters in the parameters of the equivalent circuit.
Owner:SHANGHAI JIAOTONG UNIV

Polarized Raman spectrum measurement method for microfibril orientation of plant cell wall

The invention belongs to the technical field of spectral analysis, and discloses a plant cell wall microfibril orientation polarization Raman spectrum measurement method, which comprises: 1, carrying out polarization Raman spectrum data acquisition on a sample to be measured; step 2, acquiring required data based on a data acquisition result of the polarization Raman spectrum; 3, performing nonlinear parameter fitting on the required data, obtaining an optimal parameter combination and a corresponding coefficient through a minimum error function, and performing forced symmetry post-processing on the optimal Raman tensor matrix; step 4, calculating a microfilament angle of a corresponding angle according to the symmetrical tensor parameter; in the fourth step, based on the symmetrical tensor matrix, the angle needed for rotating the tensor matrix to the main axis direction is calculated; and carrying out normalization processing on the calculated angle value. The technical problems that in the prior art, due to the fact that a nonlinear fitting algorithm is complex and prone to being affected by noise and experimental errors, the fitting convergence effect is poor, and the stability and reliability of a detection result are insufficient are solved.
Owner:ANHUI CONCH IND TECHNOLOGY RESEARCH INSTITUTE CO LTD

Method for calculating flow resistance and rotating torque of integrated water valve

A method for calculating flow resistance and rotation torque of an integrated water valve comprises the steps of 1, establishing a geometric model of a fluid domain of the integrated water valve, 2, carrying out grid division on the fluid domain, 3, importing a grid model into a solver, 4, defining physical property parameters of fluid changing along with temperature, 5, defining boundary conditions of the model, 6, calculating the rotation torque of the integrated water valve, and 7, calculating the rotation torque of the integrated water valve. Step 6, setting a pressure-velocity coupling method, a flux type and a gradient format; the torque calculation method comprises the steps of 1, establishing a three-dimensional geometric model of the integrated water valve of the electric vehicle, 2, carrying out grid division on a rubber ring and a metal part, 3, importing a grid model into an explicit dynamics solver, 4, defining nonlinear parameters of a material, 5, defining contact attributes of the model, and 6, calculating the torque of the integrated water valve of the electric vehicle. 6, defining boundary conditions of the model; and 7, creating work and submitting calculation. The simulation difficulty and period of the integrated water valve of the electric vehicle are reduced, so that sufficient time is provided for improving the structure of the integrated water valve of the electric vehicle.
Owner:SHANDONG MEICHEN ADVANCED POLYMER MATERIALS TECH CO LTD

Method for determining the influence of dislocation dipoles defects in an aluminum matrix on acoustical parameters

The application is a method for the influence of dislocation dipole defects in aluminum matrix on acoustic parameters, belonging to the technical field of discrete solution, and provides a new molecular dynamics simulation method for researching the changes of ultrasonic velocity, acoustic attenuation and acoustic nonlinear parameters based on two dislocation dipole structures, specifically, the types and quantities of dislocation dipoles in the aluminum matrix are controlled, the atomic scale acoustic simulation is carried out on the dislocation dipole models of different types and quantities by using the phase inversion technology, the cross correlation method is used to extract the sound velocity, the Hilbert transform method is used to extract the sound attenuation, and the FFT method is used to extract the acoustic nonlinear parameters for the four-phase signals, so as to realize the precise extraction of acoustic parameters. Based on the fitting relationship between the three acoustic parameters and the dislocation defects, the contribution of the dislocation defects to the acoustic parameters is determined, and the prediction from the acoustic parameters to the defect characteristics is realized.
Owner:ZHONGBEI UNIV

An adaptive control system for the cutting transmission system of a coal mining machine under complex working conditions

This invention discloses an adaptive control system for a coal mining machine cutting transmission system under complex working conditions. The system uses an extended state observer in the adaptive torque compensation controller to track the state variables of the cutting transmission system, and estimates in real time disturbances such as nonlinearity and time-varying parameters. The real-time effect of the total disturbance is compensated into the feedforward compensation disturbance term in the actual control quantity. A BP network adaptively adjusts the parameters of the second-order active disturbance rejection torque controller, and an adaptive convolutional neural network fuzzy module adaptively adjusts the output compensation of the active disturbance rejection torque compensation controller to obtain expert control rules that satisfy complex impact conditions. Nonlinear state error feedback, combined with the adjustment amount of the adaptive convolutional neural network fuzzy module, calculates the initial electromagnetic torque. After feedforward compensation, a compensated electromagnetic torque is generated, which is superimposed on the torque compensation amount generated by the PI controller. This achieves adaptive compensation control for suppressing the dynamic load of the system and effective suppression of the impact energy of the dynamic load on the cutting transmission system.
Owner:JIANGSU ZHONGJI MINE EQUIP +1