247 results about "Nonlinear parameters" patented technology

The present invention provides a way to measure and track non-linear corrections in touchscreens. Some or all of the relevant non-linear corrections may be determined automatically. Production floor test equipment may make electronic measurements, compute parameters, and load the parameters in non-volatile memory of the controller electronics. Alternatively, the controller electronics can make the electronic measurements and determine non-linear parameters. The latter embodiment of the invention permits the determination of non-linear parameters in the field, dynamically tracking changes in the non-linear characteristics of installed touchscreens that occur over time or due to environmental conditions.

The invention discloses a human body fatigue evaluation method based on brain waves. According to the method, a ThinkGearAM electroencephalogram chip is used for acquiring original brain wave signals, an built-in algorithm is used for analyzing and processing the original brain wave signals, and four kinds of parameters are given through calculation according to processed brain wave data; the four kinds of parameters include variable coefficients of five brain wave signals of original delta waves, original theta waves, original alpha waves, original beta waves and original gamma waves, two nonlinear parameters of complexity and power spectral entropy, a fatigue index F worked out through energy of four basic rhythms of the delta waves, the theta waves, the alpha waves and the beta waves in the brain waves, and two parameters of relaxation degree and attention degree extracted through the brain wave signals, and the four kinds of parameters serve as input of a probabilistic neural network (PPN), the output of the PNN serves as a human body fatigue evaluation basis, and therefore the human body fatigue can be judged according to the brain waves of people.

The invention relates to a lithium battery charge state estimating method and belongs to the technical field of batteries of electric vehicles. The lithium battery charge state estimating method aims at estimating the charge state of a lithium battery under the complex working conditions of charging and discharging at different multiplying power levels through an estimation method based on a parameter time varying observer. The lithium battery charge state estimating method specifically comprises the step that a battery charge state is regarded as a state variable to be introduced into a lithium ion battery continuous model, the upper limit of hysteresis voltages is determined according to the charging and discharging open-circuit voltage, the battery hysteresis phenomenon is considered to be a first order dynamic process related to the current absolute value, a battery polarization voltage model with parameters changing along with currents and an internal resistance model with parameters changing along with currents are structured through RC rings, battery model end voltages are structured, and a nonlinear parameter time-varying battery model is obtained. The lithium battery charge state estimating method is based on a parameter time-varying lithium ion battery equivalent circuit model, the model parameters are calibrated to be a function of current multiplying power, the characteristics of the battery can be accurately expressed, and meanwhile an existing estimation method can be easily used.

Simultaneous grayscale and geometric registration of images, such as mammograms, facilitates temporal comparison and enhances the speed and reliability of computer aided diagnosis (CAD) detection of medical abnormalities. The method generally includes optimizing a merit function, e.g., sum of squared errors, containing parameters associated with a transformation function for simultaneous geometric and grayscale registering of the images, the optimizing of the merit function being performed by determining optimal values of the parameters using data in the images and registering one image to the other by applying the geometric and grayscale transformation function using the optimal values of the parameters. The optimizing may be performed iteratively from coarse to fine resolutions using a modified Levenberg-Marquardt method for optimizing nonlinear parameters with linear regression for optimizing linear parameters. A final iteration may be performed after removing pixel value pairs from the images that correspond to outliers of a joint pixel value histogram.

The invention provides a water quality prediction method, which comprises the following steps of building a water quality prediction model on the basis of a deep belief network and a long short time memory network; training a water quality prediction model on the basis of the historical water quality time sequence data and weather data; predicting the water quality on the basis of the water quality prediction model. The invention also provides a water quality prediction device, which comprises a building module, a training module and a prediction module. The water quality prediction method anddevice provided by the invention have the advantages that the deep belief network and the long short time memory network are introduced into the water quality prediction model; a great amount of water quality time sequence data and weather data are processed by using the deep belief network; the relationship between all factors is mined; the groundwork is laid for high-precision prediction difficult to realize the multi-variable nonlinear parameter data; on the basis of the deep belief network, the mass water quality time sequence data and weather data processing results are predicted on thebasis by studying the long-time relationship between the water body quality and the time sequence by the long short time memory network; the optimum prediction effect is obtained.

Systems and methods are provided for aircraft attitude control. The aircraft attitude control may take physical parameters of the aircraft into account. For example, one or more aircraft configuration parameters, such as moment of inertia, motor lift curve, and / or axial distance may be calculated and / or taken into account based on the aircraft physical parameters. The aircraft configuration parameters may include non-linear parameters. The control systems may include feedback control systems, and may optionally use a feedforward and feedback control for angular acceleration.

The invention provides a non-linear software correction method of a linear frequency modulated continuous wave radar, belonging to the technical field of signal treatment and detection. The non-linear software correction method particularly comprises the following steps of: in a linear frequency modulated continuous wave radar receiver, carrying out analogue-to-digital conversion on amplified and filtered video echo receiving signals into digital signals; secondly, carrying out fractional order Fourier transform analysis on the digital echo signals; carrying out peak value search on a fractional order Fourier transform result in two dimensions of an order quantity and a transform frequency domain, wherein the fractional order and the frequency which correspond to a peak value show main and target time delay of non-linear frequency modulation; and calculating to obtain a frequency modulated non-linear parameter until the treatment process of the method can be completed. With the adoption of the method provided by the invention, the frequency modulated non-linear parameter can be obtained for establishing a non-linear correction reference function. The non-linear influence in the echo signals can be effectively removed by convolving the reference function and the radar echo signals.

The invention provides a method utilizing a laser displacement sensor to measure speaker parameter and a testing system for realizing the method. The method adopts stepping swept-frequency signals to stimulate a device to be measured, and simultaneously measures displacement response signals of a vibrating diaphragm of the device to be measured and current response signals flowing over the device to be measured. The signals are imported into a linear model and a large signal Volterra model of a speaker, and linear parameters and nonlinear parameters of the speaker are obtained through system identification. As the linear parameters and the nonlinear parameters of the speaker can show operating characteristics of the speaker under different amplitude input, the method can not only be applied to the design verification and the product quality detection of the speaker, but also be applied to the tone quality improvement of the speaker products.

The invention relates to a processing method of lithography machine alignment signals, comprising the following steps: setting a non-linear model for processing the alignment signals of the lithography machine silicon slice; carrying out alignment scanning on the lithography machine silicon slice to obtain position sampling data and light intensity sampling data; carrying out real-time accumulative processing on the position sampling data and the light intensity sampling data to obtain accumulation coefficient; confirming non-linear parameter initial value of the non-linear model according to a linear model containing dark current, sine coefficient and cosine coefficient; obtaining the linear parameters of the non-linear model according to the accumulation coefficient and the non-linear parameter; obtaining iteration increment of the non-linear parameter according to the accumulation coefficient and the linear parameters of the non-linear model; updating the non-linear parameters of the non-linear model according to the iteration increment; judging whether the iteration increment meets accuracy requirement so as to determine the final linear parameters and the final non-linear parameters of the non-linear model.

The invention discloses a calculating method, device and medium for the vehicle previewing distance and a steering control method. The method used for calculating the vehicle previewing distance comprises the steps that an expected path of a vehicle is obtained; the posture of the vehicle is obtained; according to the expected path and the posture of the vehicle, non-linear parameters of the expected path are obtained; and based on the non-linear parameters of the expected path, the previewing distance is calculated. In the calculating method, nonlinearity of the expected path is considered, the previewing distance of the vehicle can be more accurately calculated, and thus, more accurate vehicle steering control can be achieved.

The invention provides a loudspeaker nonlinear system identification method comprising the steps of providing an amplified excitation signal for a loudspeaker system to be tested; synchronizing a voltage signal and current signal on both ends of the loudspeaker system; acquiring a linear parameter of the loudspeaker system: according to the measured voltage signal and the measured current signal, computing the impedance curve of the loudspeaker system on a large signal condition, and matching the impedance curve by using a least square method so as to obtain the linear parameter of the loudspeaker system; acquiring the nonlinear parameter of the loudspeaker system: inputting the measured current signal into the lumped parameter model of the loudspeaker system to compute an estimated voltage signal; comparing the estimated voltage signal with the measured voltage signal and computing a voltage error signal between the estimated voltage signal with the measured voltage signal; de-correlating the voltage error signal in order remove the linear component in the voltage error signal, and acquiring the nonlinear parameter by an adaptive iteration algorithm according to the de-correlated voltage error signal.

The cerebral ischemia and anoxia monitoring system based on heart rate variance signal as one kind of medical equipment includes a signal extracting module, a cardioelectric signal treating module, and an outer communication and memory module. The signal extracting module receives cardioelectric signals from three body surface electrodes, amplifies the signals, performs isolating and analog filtering treatment and feeds the treated cardioelectric signals to the cardioelectric signal treating module; the cardioelectric signal treating module completes A / D conversion, digital filtering, heart rate variance signal extraction, non-linear parameter calculation and threshold judgment before transmitting the treated signal to the outer communication and memory module; and the outer communication and memory module completes the display, storing and communication on the signal. The present invention has low cost and other features.

A method and system for microstructural evaluation and degradation evaluation of an object are provided. The method comprises insonifying at least one subvolume of the object with ultrasonic energy at a fundamental frequency and acquiring receive energy from the object at the fundamental frequency and at least one harmonic frequency thereof. A nonlinearity parameter is determined using the receive energy. The nonlinearity parameter is then used to determine a grain size for the subvolume of the object and a variation of the grain size within the object. The nonlinearity parameter is also used to determine fatigue damage or a residual stress.

The invention aims to provide an acoustic surface wave high-order nonlinear parameter representation method for a bending fatigue state of a metal plate, and the method is used for detecting the bending fatigue state of the metal plate in real time and predicting the bending fatigue life of the metal plate and is widely applied to the fields of aerospace, machinery, traffic, chemical engineering, water conservancy and the like. The method comprises the following steps: determining parameters of an excitation signal according to the surface wave transmission distance and the acoustic velocity of a detected material; emitting a pulse string signal by a high-power ultrasonic transceiver, enabling ultrasonic wave beam to be obliquely incident to the material to generate surface waves, and interacting the surface waves with fatigue defects such as microdefects, micro-plastic deformation or microcracks generated in a bending fatigue process to generate a higher harmonic signal; recording the change of nonlinear parameters every a fixed cycle in a bending fatigue test process, comparing with a standard curve, judging whether a test piece has defects or not, emitting an early warning signal, and predicting the residual bending fatigue life of the metal plate.

The invention provides a motor signal compensation method. The motor signal compensation method comprises the following steps: acquiring an original signal and nonlinear parameters of a motor; calculating a compensation signal of the original signal according to the acquired motor non-linear parameter and a compensation formula; and transmitting the calculated compensation signal to the motor to excite the motor to vibrate. The invention further discloses electronic equipment and a storage medium. According to the motor signal compensation method, compensation processing is carried out on theoriginal signal by combining the nonlinear parameters, so that the actual vibration effect of the motor after the compensation signal is obtained is closer to the expected effect, and then the touch experience better meeting the expectation is obtained.

The invention discloses a test method and device for nonlinear parameters of a motor, and the method comprises the following steps of exciting vibration of the motor by using an excitation signal, performing synchronous information acquisition on the motor in a vibrating state to obtain a voltage measured value and a current measured value, acquiring a linear parameter initial value and a nonlinear parameter initial value of the motor, calculating a linear parameter target value of the motor according to the voltage measured value, the current measured value and the linear parameter initial value, and calculating a nonlinear parameter target value of the motor by adaptive filtering according to the voltage measured value, the current measured value, the linear parameter target value and the nonlinear parameter initial value. By measuring the nonlinear parameters of the motor, accurate control of the motor vibration is realized by using a nonlinear model to improve the control accuracyof the motor, thereby improving motor performance.

In one embodiment, a circuit comprises an adaptive predistorter and a nonlinear element coupled to an output of the predistorter. The predistorter is operative to predistort an input signal according to predistortion control parameters at a given sampling rate. The circuit further comprises an identification unit and a translation unit. The identification unit identifies nonlinearity parameters representing the nonlinearity of the nonlinear element by sampling the output of the nonlinear element at an identification sampling rate lower than twice a bandwidth at the output of the nonlinear element. The translation unit translates the identified nonlinearity parameters into the predistortion control parameters. Other systems and methods are disclosed.

The invention relates to a nonlinear parameter calculation method for simulating the aging failure of photovoltaic cell models, which includes the following steps: (1) a translucent film blocking method is adopted to decrease irradiance received by a photovoltaic panel in order to simulate the aging failure of the photovoltaic panel, and the relation between the number of translucent film blocking layers and irradiance attenuation is measured; (2) a relation curve between blocking film layer numbers (C) and aging degrees (L) is created; (3) the difference of blocking degrees is utilized to simulate the different aging degrees, a load in a photovoltaic panel circuit is regulated and the voltage and current values of the circuit are acquired, and thereby an I-V output curve of the photovoltaic panel under different irradiances and the different aging degrees is obtained; an external characteristic I-V relation of the photovoltaic panel is established; (4) for the I-V output curve of the photovoltaic panel under the different irradiances and the different aging degrees, optical parameter values are obtained by parameter identification. The nonlinear parameter calculation method can obtain the nonlinear parameter change laws of the aging failure of the photovoltaic cell models.

The invention discloses a feedback control method of a wind energy converting system based on a fuzzy performance estimator and designs a T-S fuzzy state feedback control system including the fuzzy performance estimator specifically to characteristics of strong nonlinearity and parameter uncertainty of the wind energy converting system, belonging to the feedback control field. Firstly, a nonlinear model and a T-S fuzzy model of the wind energy converting system are provided; secondly, the fuzzy performance estimator of the system is designed based on the T-S fuzzy model of the wind energy converting system; then, a linear controller is designed in each linear local model respectively; and a fuzzy state feedback controller of a global model is constituted by dint of membership function. The method provided by the invention has the advantages of a controller is designed based on the fuzzy performance estimator; the feedback control method ensures that a closed-loop control system has good tracking performance; simultaneously, preferable dynamic performance and stable-state performance can be acquired.

The invention provides a heart rate variability (HRV) nonlinear characteristic-based automatic diagnosis method for congestive heart failure (CHF), comprising the steps of: (1) extracting heartbeat intervals from a collected body surface electrocardiogram signal to form a heart rate variability sequence, and extracting three sensitive characteristic parameters (including linear and nonlinear parameters) of the sequence; and (2) preprocessing the three sensitive characteristic parameters obtained in step (1), inputting to an artificial neural network, and obtaining an automatic diagnosis result of the congestive heart failure through a determined artificial neural network model. Automatic diagnosis of the HRV is realized by using the HRV noninvasively collected from a body surface, and an examinee is not strictly limited in state (the examinee is not required to lie flatly or sit quietly); the method can be applied to data collected in daily life only if collection time reaches 4h; and actual data tests show that the diagnosis effect is excellent.

The invention provides a calculation method of transformer harmonic loss based on a frequency conversion property. The calculation method is characterized by comprising a direct-current resistance loss of a transformer winding under a non-linear loading condition and other stray losses of the transformer winding under the non-linear loading condition, calculating an eddy-current loss correction factor of the transformer winding, modeling the transformer by the transformer harmonic loss based on the frequency conversion property and the like, and calculating and analyzing the harmonic loss. The method provided by the invention has the advantage of accuracy of loss calculation of the transformer under the non-linear loading condition; compared with the traditional harmonic calculation method, on the basis of analyzing the frequency conversion property of a winding model, the harmonic loss is corrected by considering an overlapping calculation of an equivalent non-linear parameter of each subharmonic lower winding and the harmonic loss; therefore, the calculation method has the advantages of stronger adaptability and higher actual application value.

Devices and techniques for estimating the concentration of one or more agents in a fluid environment employ a plurality of measurements of a sensor attribute that changes in response to an agent. Measurements taken before the agent / reagent combination reaches a steady-state may be used. The plurality of measurements are processed using a nonlinear, parametric model of the interaction between the sensor and the agent to determine the concentration of the agent. The model takes into account the finite capacity of a sensor reagent. The model characterizes the interaction of individual agent / reagent combinations with a set of parameters. These parameters require minimal testing to calculate. The invention enables the response of a sensor to an agent over the entire range of agent concentration levels to be efficiently and accurately characterized. The invention also enables the prediction of collective responses given parameters characterizing a plurality of agent / reagent combinations.

The invention discloses a substation three-dimensional live-action monitoring stationing method based on nonlinear parameter optimization calibration. The method comprises the steps that a three-dimensional substation physical model is imported; an area coverage to be monitored is acquired based on the model, and the type and the physical parameters of a camera are determined; a position hypothesis test based on the area to be monitored is carried out: three monitor points are selected on the boundary of the area to be monitored, and the coordinates of the points are calculated; based on the relationship between a model coordinate system and a camera coordinate system, the physical position and the orientation of the camera in a three-dimensional space are derived; hypothesis verification based on camera object positioning is carried out: based on a perspective projection principle, the relationship between the imaging picture of camera motion trajectory and a covered three-dimensional space entity area is analyzed; and through visualization, the three-dimensional space entity area of camera projection and the area to be monitored is compared. Compared with a traditional method, the method has the advantages that the monitor area of the same size is ensured, and at the same time the system configuration is optimized, and unnecessary device input is saved.

The method is applicable to conventional sound-frequency measuring meter. Feeding-in an adjustable DC current shifts the voice coil a certain displacement from equilibrium position. Under different displacements of the coil, using conventional sound-frequency measuring meter measures characteristic of electrical impedance of speaker unit. Based on model of nonlinear electrical impedance, using technique of system identification obtains nonlinear parameters of speaker unit. The said measurement of nonlinear parameter is related to measuring non-linear force factor, non-linear equivalent force and non-linear inductance of voice coil. Using conventional sound-frequency measuring meter, the invention can measure curve of electrical impedance of speaker unit, and caries out system identification for measured impedance curve of speaker unit.

The invention provides a method for detecting interface contact strength by double frequency ultrasound, which mainly comprises the following steps of: generating double frequency ultrasound exciting signals by using a signal generator, and amplifying by using a power amplifier; transmitting the signals by utilizing a transmitting transducer, receiving the signals by utilizing a receiving transducer after the transducers are calibrated; exciting the double frequency ultrasonic signals in a sample to be detected, and processing the signals by utilizing fast Fourier transform; converting the obtained electric signal amplitude into the absolute displacement amplitude; and calculating a nonlinear parameter, a linear contact strength value and a second-order contact strength value. A calibration procedure for absolute vibration amplitude is introduced, and the concrete contact strength value can be calculated, so the quantitative detection on a solid interface can be realized. The double frequency ultrasound is adopted for detection; and compared with the conventional solid interface contact strength ultrasound detection method, the technology can effectively enhance the detection for the contact strength of the solid interface.

The invention discloses a digital assisted simulation domain interference cancellation method and device. The method comprises four steps including signal transmitting, signal feedback, signal reconstruction and signal receiving; nonlinear parameter vectors are estimated by adoption of a nonlinear extraction unit in the signal feedback step; and reconstructed digital transmission signals are calculated by adoption of a nonlinear reconstruction unit in the signal reconstruction step. The device comprises a signal transmitting loop, a signal feedback loop, a signal reconstruction loop and a signal receiving loop. By means of the method, nonlinear interference introduced by a transmitting radio-frequency channel can be effectively inhibited; nonlinear estimation and parameter adjustment can be conveniently carried out in a digital domain; estimation of a multi-path channel between the transmitting radio-frequency channel and a receiving radio-frequency channel and parameter adjustment can be conveniently carried out in the digital domain; therefore, the method can be easily expanded to other application scenes; and the robustness is relatively high.

The invention discloses a test adapter for analog-to-digital converter nonlinear parameters. The test adapter comprises a general test mother board and a special test sub board. The invention further discloses a test method for analog-to-digital converter nonlinear parameters. The test method includes the following steps: building a slope generating function; inputting slope analog voltage into an analog-to-digital converter to be tested; capturing digital output signals of the analog-to-digital converter to be tested; counting the number of total sampling points and all stages of codes in the digital output signals; calculating the average occurrence number of the codes; and calculating differential nonlinear parameters and integral nonlinear parameters. According to the test adapter and the test method for analog-to-digital converter nonlinear parameters, the differential nonlinear parameters and the integral nonlinear parameters of the high-speed and high-accuracy analog-to-digital converter are accurately measured through a linear slope histogram and the natural statistical property of the analog-to-digital converter. The test method is higher than the conventional method and easy to operate, and reduces inaccuracy degree of measurement error to a certain extent.

The application provides a loudspeaker nonlinear parameter testing device system which comprises a direct current offset signal output device, a laser distance measuring instrument and a loudspeaker testing system. The application further discloses a loudspeaker nonlinear parameter testing method which comprises the steps that: the direct current offset signal output device applies a direct current offset voltage signal to a loudspeaker to be tested; the laser distance measuring instrument measures an offset displacement of a loudspeaker voice coil; under a condition that values of direct current offset voltage signals at both ends of the loudspeaker to be tested are kept unchanged, an impedance curve and a displacement-voltage transfer function curve of the loudspeaker are acquired by the loudspeaker testing system; a value of each nonlinear parameter of the loudspeaker in a state that the voice coil is offset is calculated out; and the steps above are repeated to acquire a nonlinear curve of each nonlinear parameter. According to the loudspeaker nonlinear parameter testing device system and testing method provided by the application, the loudspeaker is directly tested by equipment, such as the loudspeaker testing system, the laser distance measuring instrument and the like, and the nonlinear parameters of the loudspeaker are directly acquired, so that accuracy of measured data is effectively improved.

The invention provides an ultrasonic nondestructive detection method of material micro-crack expanded size. The method comprises the following steps: constructing a measurement system; manufacturing multiple reference samples, and performing repeated fatigue test on each reference sample; performing metallographic observation after each fatigue test so as to obtain a micro-crack length of each reference sample, and performing ultrasonic nonlinear Lamb wave measurement to compute a nonlinear parameter beta0 of each reference sample; obtaining a nonlinear parameter-fatigue life curve, marking micro-crack sizes corresponding to various points on the curve; performing nonlinear ultrasonic Lamb wave measurement on the to-be-tested sample to obtain the nonlinear parameter beta0, and finding outthe point corresponding to the nonlinear parameter beta0 in the above curve, and finding the length of the micro-crack corresponding to the point. A relationship of the micro-crack size and the nonlinear parameter is used for judging the micro-crack length and representing the fatigue damage, in-service equipment cannot be damaged, and the micro-crack state of the material on active can be quicklydetected at low cost.

A method and system for microstructural evaluation and degradation evaluation of an object are provided. The method comprises insonifying at least one subvolume of the object with ultrasonic energy at a fundamental frequency and acquiring receive energy from the object at the fundamental frequency and at least one harmonic frequency thereof. A nonlinearity parameter is determined using the receive energy. The nonlinearity parameter is then used to determine a grain size for the subvolume of the object and a variation of the grain size within the object. The nonlinearity parameter is also used to determine fatigue damage or a residual stress.