102 results about "Frequency characteristic" patented technology

This invention relates to a method for measuring the stability margin of a constant-temperature hot-wire anemometer based on in-situ open-loop frequency characteristics, belonging to the field of fluid measurement and automatic control technology. The method disclosed in this invention includes the following steps: S1. Connecting an ultra-low frequency low-pass filter to the closed-loop circuit to form an in-situ open-loop system with a DC closed loop and an AC open loop; S2. Injecting a sweep frequency excitation signal E at the bias circuit. stimu And measure the output response E of the amplifier circuit. a By comparing the amplitude ratio and phase difference of the two, the open-loop frequency response G of the system under actual operating conditions of the hot wire is obtained. open (jω); S3. According to G open (jω) Obtain the phase margin of the system and determine its stability. This invention proposes a new method for measuring the stability margin of a constant-temperature hot-wire anemometer, transforming the complex system stability problem into a measurable and analyzable open-loop frequency characteristic stability margin problem, providing a direct and reliable engineering basis for the circuit design of constant-temperature hot-wire anemometers.

The application discloses a lightning impulse grounding grid frequency characteristic analysis method, system, device and medium, including: obtaining initial sample data; using the sample and a preset test frequency set to construct at least two different structure rational function interpolation models, and calculating the output residual thereof in the test frequency band; determining the target frequency point with the maximum modeling uncertainty according to the residual, calling the moment method to supplement high-precision response samples at the point; based on the updated sample set, constructing a diagonal or near-diagonal form rational interpolation model, and judging whether the prediction error of the model at the target frequency point is lower than a preset convergence threshold; if the convergence condition is not met, returning to the multiple model construction step, reiterating using the current sample set until the error meets the standard, and finally outputting the grounding grid frequency response characteristics covering the lightning impulse frequency band. The application realizes efficient analysis of the grounding grid frequency characteristics under lightning impulse, and effectively reduces the time used for analyzing the grounding grid frequency characteristics under lightning impulse.

The application discloses a kind of garden plant health condition detection and early warning system based on spectral analysis, including adjustable frequency excitation light source, fluorescence detector, quadrature phase-locked demodulation module, phase frequency characteristic analysis module, early warning control unit and early warning output terminal, adjustable frequency excitation light source emits broadband sweep frequency modulation perturbation excitation light, quadrature phase-locked demodulation module executes operation filtering natural background stray light to the electric signal collected, phase frequency characteristic analysis module extracts characteristic relaxation frequency parameter when absolute phase delay parameter reaches forty-five degrees phase angle, early warning control unit sends instruction lock frequency and applies saturated light flash pulse, system calculates dynamic apparent electron transfer rate parameter, and according to temperature drift compensation baseline, executes double tolerance threshold comparison determination plant physiological stress state.The application avoids the defect of detection frequency band misplacement, eliminates the interference of strong background light and air temperature fluctuation, realizes the multi-dimensional joint early warning of early physiological stress.

The invention relates to a method for detecting a hairspring or a hairspring blank arranged as a hairspring, the hairspring having to have at least one preset oscillation frequency, the method comprising the following steps: a. applying a time-varying vibration excitation to the hairspring or the hairspring blank to cover a preset frequency range; b. determining at least one characteristic of the oscillation frequency of the hairspring or the hairspring blank, such as a resonance peak, during the vibration excitation in the preset frequency range; c. providing the oscillation frequency characteristic determined in step b to a prediction machine to determine the stiffness of the hairspring or the hairspring blank and / or to determine whether a dimensional correction of the hairspring or the hairspring blank is required to achieve the preset oscillation frequency.

A bearing damage detection system includes a rotation sensor that detects rotation of a rolling bearing and outputs a rotation signal, a rotation fluctuation extraction section that extracts rotation fluctuation of the rolling bearing from the rotation signal and generates a rotation fluctuation signal, a frequency analysis section that performs frequency analysis on a waveform of the rotation fluctuation signal and derives a frequency characteristic, a peak intensity calculation section that derives a peak intensity corresponding to bearing damage from the frequency characteristic, and a damage detection section that detects bearing damage of the rolling bearing based on the peak intensity. The rotation fluctuation extraction section derives a waveform of the rotation fluctuation signal from which various noises are removed.

The application relates to the technical field of electromagnetic measurement, and discloses a signal optimization processing method and system for electromagnetic frequency sensitive material, the method comprising the following steps: performing scanning measurement on an original response signal of the electromagnetic frequency sensitive material under frequency domain excitation to obtain amplitude-frequency characteristic parameters and phase-frequency characteristic parameters; performing frequency domain conversion analysis on the amplitude-frequency characteristic parameters and the phase-frequency characteristic parameters to obtain a complex spectrum change gradient; identifying the sensitivity response of dynamic frequency of the electromagnetic frequency sensitive material, and merging the identified frequency point groups into characteristic frequency subbands; mapping the characteristic frequency subbands into a frequency optimization strategy library to obtain an optimization strategy; performing compensation correction on the original response signal to obtain an optimized signal; performing signal-to-noise ratio evaluation on the optimized signal, and iteratively optimizing the frequency optimization strategy library according to the evaluation result, so that the signal optimization processing effect of the electromagnetic frequency sensitive material is realized; and the application can improve the signal optimization processing efficiency of the electromagnetic frequency sensitive material.

A blood purification device (1) comprises: a blood purifier (3) capable of purifying blood; a blood circuit (2) including an arterial-side blood circuit (21) which has an arterial-side puncture needle (211) attached on the distal end thereof, and a venous-side blood circuit (22) which has a venous-side puncture needle (221) attached on the distal end thereof; an impedance measurement unit (5) including an oscillator (53) that applies an alternating-current voltage across an arterial-side electrode (51) provided to the arterial-side blood circuit (21) and a venous-side electrode (52) provided to the venous-side blood circuit (22), the impedance measurement unit being capable of measuring frequency characteristics of the impedance between the arterial-side electrode (51) and the venous-side electrode (52); and a puncture determination unit (72) for determining, on the basis of the measured frequency characteristics of the impedance, whether a patient has been punctured normally. The blood purification device also comprises a frequency range determination unit (70) for determining the frequency range of the alternating-current voltage applied by the oscillator (53) in accordance with the liquid in the blood circuit (2).

This invention provides an analytical method for a two-zone frequency full response model considering nonlinear elements, belonging to the field of analytical analysis of power system frequency response. First, considering the influence of nonlinear elements, a single-machine frequency full response model considering nonlinear elements is established. A piecewise modeling method for nonlinear elements and a full response analysis theory are proposed to achieve analytical analysis. Second, considering the influence of frequency spatiotemporal distribution characteristics, a two-zone equivalent frequency response model is established. An analytical method based on the model's vibration equation is proposed to achieve analytical analysis of regional frequencies. Finally, a two-zone frequency full response model considering nonlinear elements is established to achieve dynamic analytical characterization of the system's frequency response. This invention improves the accuracy of the model's description of the dynamic frequency characteristics of power systems after large disturbances, providing a new approach to solving the frequency security problem of power systems under the coupled influence of nonlinear elements and frequency spatiotemporal distribution characteristics, and contributing to the safe and stable operation of power systems.

This application discloses a method for detecting living beings inside a vehicle and an alarm method for detecting children left behind in a vehicle. The main technical solution includes: acquiring radar echo signals from the interior environment of the target vehicle; analyzing the respiratory frequency of a living being based on the frequency characteristics of the radar echo signals to obtain respiratory frequency estimation information, wherein the frequency characteristics include frequency amplitude and / or frequency phase; and determining whether a living being exists in the vehicle's interior environment based on the respiratory frequency estimation information. This method can effectively identify weak, periodic respiratory signals from a noisy background, improving the accuracy and reliability of living being detection and effectively reducing the number of missed and false alarms regarding living beings left in the vehicle.

The application provides a multi-target user detection synchronization method, system and storage medium based on a sweep frequency spread spectrum carrier modulation technology. A transmitting end preferably constructs a Gold sequence as a spread spectrum code by using an m sequence, modulates the Gold sequence on a periodic linear sweep frequency carrier in a BPSK mode by using an S2C modulation mode, and forms a synchronization header signal with a sharp autocorrelation peak and a low cross-correlation side lobe. A receiving end preliminarily positions the synchronization header by correlation detection, and then performs a de-skew processing on the received signal, multiplies the received signal with a local linear frequency modulation reference signal, and performs a band pass filtering, so as to convert the wideband sweep frequency signal into a single frequency signal, and greatly reduce the processing complexity. On this basis, the coarse synchronization utilizes the correlation detection combined with the maximum likelihood method to preliminarily time in the time domain, and the fine synchronization finely adjusts according to the frequency characteristics of the de-skewed signal. The method can still realize the robust multi-target signal detection and high-precision positioning in a complex underwater acoustic multipath environment, and has good engineering practicability.

This disclosure relates to the field of insulating material testing, including a method and system for evaluating the nonlinear strength of insulating materials based on high-frequency component analysis. The method involves applying an excitation electrical signal of a first preset frequency to the insulating material under test; acquiring the response signal obtained by the insulating material in response to the excitation electrical signal based on a second preset frequency; performing time-frequency transformation on the response signal to obtain the frequency characteristics of various preset higher harmonic components; and determining the evaluation result of the nonlinear strength of the insulating material based on the frequency characteristics of these higher harmonic components. This method allows for obtaining the evaluation result of the nonlinear strength with a single excitation and response acquisition; it eliminates the need for multi-voltage point step testing in traditional techniques, shortening the testing cycle, improving testing efficiency, and enabling efficient, accurate, and standardized determination of the nonlinear strength evaluation result.

The present technology relates to an information processing apparatus, method, and program that enable sound field control having a higher degree of freedom. The information processing method of the present invention involves an information processing apparatus performing the following: identifying a parameter relating to the complex acoustic impedance of a resonator, or a sound absorber that uses the resonator, installed on a surface forming a target space, said parameter being identified on the basis of a target sound pressure frequency characteristic at an evaluation point in the target space and an acoustic analysis model for obtaining the sound pressure frequency characteristic at any point in the target space; and identifying the shape of the sound absorber on the basis of the parameter. The present technology can be applied to an acoustic metamaterial.

This invention discloses a rapid evaluation method for the enhancement factor of the dynamic coefficient by the high-frequency component of a strong impact load, belonging to the field of structural dynamic response analysis technology. This method performs time-frequency domain energy accumulation analysis on the strong impact load signal, extracts the concentrated frequency of load energy and its proportion in the total energy, and then, based on this, combines the dynamic amplification factor under the triangular time history assumption to quantitatively calculate the enhancement factor of the dynamic coefficient by the high-frequency component of the strong impact load. This method is further extended to arbitrary frequency components and the entire frequency band to obtain the comprehensive enhancement result of the dynamic amplification factor by the high-frequency effect of the strong impact load. Compared with traditional dynamic analysis methods based solely on idealized time history assumptions, this invention can introduce the real time-frequency characteristics of strong impact loads while maintaining computational efficiency, effectively compensating for the insufficient consideration of high-frequency excitation effects. It is applicable to rapid dynamic response evaluation in engineering fields such as aerospace structures, high-frequency components, and precision equipment.

According to one embodiment of the present invention, a system for detecting deep voice generated by generative artificial intelligence is provided, comprising: a memory for storing instructions; and one or more processors for executing said instructions, wherein the processor extracts a feature vector including frequency characteristics and temporal change patterns from input voice data, inputs said extracted feature vectors to an ensemble artificial intelligence model including a first AI model which is an acoustic model, a second AI model which is a language model, and a third AI model which is a pattern recognition model to calculate each individual deep voice probability, measures the signal quality of said input voice data to calculate a signal-to-noise ratio (SNR), calculates a final deep voice probability through an adaptive weight allocation algorithm that varies the weights to be applied to said AI model in real time based on said calculated SNR value, and generates a deep voice suspicion alarm when said final deep voice probability exceeds a threshold value.

The invention discloses an acceleration waveform reproduction method of a two-degree-of-freedom electro-hydraulic vibration table. The method comprises the following steps: calculating an impedance matrix of a two-degree-of-freedom electro-hydraulic acceleration servo system; initializing parameters of a two-degree-of-freedom frequency characteristic compensation controller; optimizing parameters of the two-degree-of-freedom frequency characteristic compensation controller; constructing a discrete pulse transfer function matrix of the two-degree-of-freedom frequency characteristic compensation controller; calculating the frequency characteristic of the system after the two-degree-of-freedom frequency characteristic compensation controller and the two-degree-of-freedom electro-hydraulic acceleration servo system are connected in series; constructing a discrete pulse transfer function matrix of the two-degree-of-freedom waveform reproduction controller; the two-degree-of-freedom electro-hydraulic acceleration servo system is driven to move. According to the method, the time domain peak error of the acceleration output signal and the acceleration reference signal of the two-degree-of-freedom electro-hydraulic acceleration servo system can be controlled within 20%, and the waveform reproduction precision of the acceleration reference signal is obviously improved.

The present application belongs to the technical field of inertia evaluation, and discloses a minimum inertia demand evaluation method of a direct current outward transmission system considering the difference of multi-frequency modulation resource support characteristics, which firstly analyzes the frequency response characteristics of each frequency modulation resource in the direct current outward transmission system under a typical control mode, establishes a system frequency response model considering the difference of wind power, photovoltaic and extra-high voltage direct current frequency response characteristics, and reveals the influence mechanism of different frequency modulation resources on the system frequency characteristics. Secondly, an equivalent inertia calculation model of the system considering the inertia support role of wind power and photovoltaic is constructed, and a minimum inertia demand evaluation method based on the constraint of initial frequency change rate is proposed. Then, considering the influence of the direct current frequency limiting controller on the maximum frequency deviation, a minimum inertia evaluation scheme of the direct current outward transmission system considering the frequency dynamic safety constraint is designed to support the efficient, stable and continuous transmission of new energy power generation.

The application relates to the field of avionics, and discloses a lifting speed filtering method and system based on a second-order Butterworth filter, which comprises the following steps: collecting an atmospheric pressure signal of an airplane in real time, calculating an air pressure height according to the atmospheric pressure signal, calculating a lifting speed signal according to the air pressure height, performing amplitude-frequency characteristic analysis on the lifting speed signal to determine a cutoff frequency of the second-order Butterworth filter, dynamically adjusting the cutoff frequency of the second-order Butterworth filter according to the flight state of the airplane, inputting the lifting speed signal into the second-order Butterworth filter with the adjusted cutoff frequency, and obtaining a filtered lifting speed signal. The application realizes scientific design of filter parameters by performing amplitude-frequency characteristic analysis on the lifting speed signal and obtaining a digital filter structure through denormalization processing and bilinear transformation, determines the cutoff frequency based on the physical characteristics of the signal, and avoids the disadvantages of selecting parameters by experience in the traditional method.

The application discloses a power grid time frequency real-time correction method and system based on dynamic monitoring, comprising: capturing a continuous timestamp sequence from a power grid node, obtaining a time deviation signal; using an adaptive dispersion compensation algorithm to process the time deviation signal, obtaining a restored time frequency characteristic; through feature comparison, obtaining a parasitic interference index from the restored time frequency characteristic; if the parasitic interference index exceeds a preset interference threshold, processing the restored time frequency characteristic through a parasitic component suppression filter to obtain pure main frequency data; according to the comparison between the pure main frequency data and the time deviation signal, obtaining an adjustment instruction sequence; and according to the adjustment instruction sequence, performing real-time correction on the power grid time frequency. Through the fusion of multi-stage sampling, dispersion compensation and closed-loop control, the application significantly improves the power grid time synchronization accuracy and stability, effectively suppresses parasitic interference, and realizes real-time correction.

The present application relates to a kind of fusion frequency feature MVS three-dimensional reconstruction method, comprising: constructing MVS dataset;Wherein, the MVS dataset is the indoor MVS dataset containing several scans, each scan has several views under several different illumination conditions;HL-MVSNet model is constructed;Wherein, the HL-MVSNet model includes: feature extraction network, attention module, cost volume generation module;The MVS dataset is used to train the HL-MVSNet model, and MVS three-dimensional reconstruction model is obtained;Using the MVS three-dimensional reconstruction model, fusion frequency feature MVS three-dimensional reconstruction is carried out.The present application realizes the significant improvement in reconstruction accuracy and integrity.

This invention belongs to the field of fault diagnosis technology, specifically relating to an online monitoring method for bearing abnormal noise based on acoustic signature frequency feature analysis. The method includes the following steps: acquiring a continuous time-domain acoustic signature signal of the bearing during operation; performing detrending and pre-whitening processing on the continuous time-domain signal to obtain a preprocessed discrete signal sequence; performing a Fourier transform on the discrete signal sequence to obtain the amplitude spectrum; calculating the spectral fluctuation complexity index based on the amplitude spectrum; determining the optimal decomposition level for variational mode decomposition based on the spectral fluctuation complexity index; and using the optimal decomposition level to decompose the discrete signal sequence to obtain several intrinsic mode components. This invention effectively distinguishes between mechanical fault impacts and random environmental interference through adaptive parameter optimization and a dual feature interlocking mechanism, significantly improving the accuracy and robustness of online monitoring.

This application relates to the field of DC transmission protection technology, and particularly to a fault identification method for hybrid three-terminal high-voltage DC transmission lines based on the DC boundary voltage energy ratio and its application. By analyzing the boundary frequency characteristics of the DC line, rectifier side, and inverter side of the system, frequency characteristic curves of each boundary are obtained. Based on the frequency response characteristics of the overall system boundary frequency characteristic curve, highly distinguishable characteristic frequency bands are determined. When a fault occurs in the system, DC voltage signals at both ends of the rectifier / inverter side are acquired, and wavelet packet decomposition is performed on the acquired signals to extract the energy within the characteristic frequency bands. Based on the energy and characteristics of the two characteristic frequency bands, identification criteria for fault location and fault polarity are constructed. This enables rapid fault identification of hybrid three-terminal DC systems without the need for communication, thereby improving the safety and reliability of hybrid three-terminal high-voltage DC transmission lines. The aim is to solve the problem of fault type identification in hybrid three-terminal DC systems.

The application provides a probe frequency response calibration parameter determination method, a measurement system and a storage medium. The calibration parameter determination method introduces a composite test signal containing a steady-state sweep signal and a transient pulse signal. Based on the data sets obtained by responding to the same test signal under two conditions that the calibration system is not connected to the probe and is connected to the probe, the de-embedding calculation is performed, that is, the amplitude is divided to eliminate the link gain deviation, and the phase is subtracted to peel off the channel phase offset, the accurate extraction of the independent frequency response characteristics of the probe is realized, and the frequency response calibration parameter of the probe is determined. The application eliminates the system error introduced by the test environment and the rear-end measurement link, improves the calibration accuracy of the amplitude-frequency characteristics and the phase-frequency characteristics of the probe in the whole working frequency band, provides a reliable basis for the oscilloscope and other measurement equipment to implement accurate real-time anti-distortion compensation in actual signal capture, and ensures the restoration authenticity of the whole measurement system in high-frequency and wideband signal testing.

The application belongs to the technical field of signal testing, and relates to a high-speed signal time-frequency characteristic automatic measurement method and a measurement control system, which are applied to a computer device, the computer device is connected with a mobile device and a vector network analyzer, the mobile device comprises a mobile base and a six-axis mechanical arm arranged on the mobile base, the six-axis mechanical arm is used for clamping a radio frequency probe to measure test points of a to-be-tested object, the vector network analyzer is used for acquiring frequency domain response data of the radio frequency probe scanning test points, and the frequency domain response data is uploaded to the computer device, the measurement process comprises the following steps: establishing a communication connection, loading a measurement task file, sequentially performing measurement operation control on each test point according to the measurement task file, acquiring frequency domain response data, pre-processing the acquired frequency domain response data, and outputting and displaying a time domain impedance image. The application realizes the whole process of signal measurement automation, improves the signal measurement efficiency and result consistency, and reduces the human operation risk.

The application relates to the technical field of fault detection, and discloses a rotating equipment bearing fault detection method, device, equipment and storage medium, the method comprising the following steps: determining a vibration sampling frequency and a rotating speed sampling frequency; collecting vibration information of a rotating equipment in a start-stop process based on the vibration sampling frequency, and obtaining a vibration signal; collecting rotating speed information of the rotating equipment in the start-stop process based on the rotating speed sampling frequency, and obtaining a rotating speed signal; associating the vibration signal and the rotating speed signal, and obtaining a bearing demodulation spectrum; and judging whether a bearing to be analyzed has a fault based on the bearing demodulation spectrum. The application can effectively extract low-frequency characteristics of early bearing faults, enhance the distinguishability of fault signals, and effectively improve the diagnosis precision of bearing faults.

Embodiments that translate a sensor measurement to a frequency characteristic are disclosed. The frequency characteristic can be wirelessly detected by a reader device. The detected frequency characteristic can be used to determine the corresponding sensor measurement. Devices utilizing this approach can be characterized or calibrated to increase accuracy. Systems and methods utilizing the approaches are also described.

The application discloses a transformer partial discharge ultrasonic signal direct wave discrimination and positioning method and system, and relates to the technical field of electrical equipment state monitoring and fault diagnosis. The method comprises the following steps: acquiring a broadband ultrasonic signal and performing time domain preprocessing to obtain a standardized discrete sequence; performing zero-phase shift decoupling by using variational mode decomposition and separating high-frequency and low-frequency characteristic components according to a frequency spectrum barycenter; applying a discrete Teager energy operator with a non-negative correction to extract a transient energy sequence; constructing a time-energy probability density distribution through adaptive background suppression and normalization; calculating a JS divergence and comparing the JS divergence with a threshold value to discriminate a direct wave; and constructing a time difference of arrival equation set based on an effective direct wave and solving a three-dimensional position by using an optimization algorithm. The application eliminates filter phase distortion and realizes high-precision partial discharge source positioning without amplitude and sampling rate constraints.

This non-contact voltage sensor device comprises: a probe electrode (10) that observes an AC voltage on a power line (2) having a conductor (2a) to which power is supplied from an AC power supply (1) and an insulator 2b covering the conductor (2a), the probe electrode (10) being in a state of electrical non-contact with the conductor (2a) in the power line (2); a dielectric relaxation compensation circuit (31) which has an input end electrically connected to the probe electrode (10) and which simulates the complex impedance from the conductor (2a) in the power line (2) to said input end; and a frequency compensation circuit (32) which has an input terminal (32a) electrically connected to an output end of the dielectric relaxation compensation circuit (31) and which compensates for the frequency characteristics of the amplitude and phase of a waveform in the AC voltage from the dielectric relaxation compensation circuit (31).

A current sensor including a busbar through which a current to be measured flows and a magnetic sensor disposed to detect a magnetic field generated by the busbar includes a conductor comprising a nonmagnetic material. The conductor is disposed opposite the busbar with the magnetic sensor interposed between the conductor and the busbar. The current sensor is capable of suppressing the occurrence of problems associated with frequency characteristics of the current sensor in which measurement errors increase due to the skin effect, which is influenced by the frequency of currents to be measured flowing through a busbar, and provides good measurement accuracy.