214 results about "Frequency wave" patented technology

The invention relates to a time-varying power high-precision calculation technology of an electric drive system under strong electromagnetic noise interference, and mainly solves the problem of inaccurate power calculation of the electric drive system under strong electromagnetic environment noise and frequency time-varying fluctuation scenes. According to the core technology, a dominant frequency fluctuation curve of a signal is obtained through dynamic tracking of a dominant frequency, and a dynamic band-pass filter changing along with the dominant frequency of the electric drive system is constructed; suppressing pulse noise by combining amplitude self-adaptive filtering of a nonlinear weighting function; a phase demodulation technology fusing zero crossing point correction and Hilbert transform is adopted to eliminate the phase interference problem caused by complex waveforms and weak noise signals; and finally, establishing a time-varying power physical model based on the sliding window. According to the technology, the power calculation accuracy of the electric driving system under the conditions of strong field environmental noise and continuous main frequency conversion is remarkably improved.

The invention discloses a broadband wave-absorbing material based on an MAX-phase metasurface structure and an impedance matching optimization method of the broadband wave-absorbing material. The wave-absorbing material comprises an MAX-phase ceramic substrate and periodic metasurface structures which are arranged on the surface of the MAX-phase ceramic substrate in an array mode and composed of conductive resonance units. The resonance units are isolated through gaps, an equivalent R1L1C1 series resonance circuit is formed in an electromagnetic field, and a base body is equivalent to a parallel resistor R2. By establishing an equivalent circuit model and optimizing parameters R1, L1, C1 and R2, impedance matching of the wave-absorbing material in a target frequency band can be regulated and controlled, so that the wave-absorbing material at least has an absorption peak of which the reflection loss is less than-10 dB. According to the optimization method, electromagnetic simulation and circuit simulation are combined, optimized circuit parameters are reversely mapped into structure geometric parameters, material preparation is guided, and accurate design and broadband absorption of the wave absorbing performance are achieved.

The invention belongs to the technical field of comprehensive utilization of ocean renewable energy sources, and particularly relates to a pilot frequency coupling-based wind wave energy multi-degree-of-freedom broadband control method, which comprises the following steps of: performing frequency domain identification on wind wave environment characteristics, and constructing a wind wave pilot frequency energy coupling model; based on the motion response characteristics of the multi-degree-of-freedom floating platform, designing a pilot frequency energy regulation and conversion mechanism; a full-working-condition dynamic optimization control strategy is adopted, and cooperative operation and energy flow self-adaptive distribution of the wind energy conversion unit and the wave energy conversion unit are achieved. Aiming at the significant difference and relevance of wind energy and wave energy in frequency characteristics, time scale and spatial distribution, a pilot frequency wind wave coupling dynamic model is established, and broadband capture of low-frequency wind-induced and high-frequency wave-induced coupling energy is realized under complex sea conditions through multi-degree-of-freedom motion decoupling and state observation, so that the wind-induced and high-frequency wave-induced coupling energy is obtained. The energy utilization rate, the attitude stability and the structural safety of the system are effectively improved, and good robustness and engineering adaptability are achieved.

The invention provides a TMD lockout control method for motion suppression of a semi-submersible platform, and the method comprises the steps: carrying out the frequency domain decomposition of a random wave predicted by a target sea condition, obtaining the energy distribution of each frequency component, obtaining the equivalent amplitude of each frequency component according to the energy distribution, considering the amplitude response of the platform under the action of waves of different frequencies, and achieving the motion suppression of the semi-submersible platform. The method comprises the following steps of: calculating a weight ratio of platform motion response caused by each frequency component under the action of random waves by integrating three types of information, namely amplitude, amplitude response and motion suppression effect, and finally carrying out weighted combination on the locking time corresponding to each frequency component according to the weight ratio, so as to obtain the motion suppression effect of the platform. And the optimal locking control time suitable for the current random wave is obtained. According to the method, a high-complexity non-causal control command does not need to be deduced, control parameters can be updated in real time according to short-term sea condition changes, pitching response of a platform is effectively reduced, and comprehensive optimization control over multi-frequency waves is achieved.

The invention discloses a magnetic suspension bearing displacement detection method and device, a magnetic suspension bearing system, a storage medium and a computer program product, an axial displacement detection area of a magnetic suspension bearing is provided with four displacement detection probes used for detecting axial displacement of a rotor, and the four probes are divided into two groups; the first group of two probes are installed along a first symmetrical direction, the second group of two probes are installed along a second symmetrical direction orthogonal to the first symmetrical direction, the design parameters of the same group of probes are consistent, and the design parameters of the different groups of probes are not consistent; the method comprises the following steps: carrying out mean value and difference operation on signals acquired by four probes to eliminate radial coupling interference; and filtering the signal subjected to mean value operation and differential operation by adopting same-frequency notch processing so as to filter radial coupling interference. According to the scheme, high-precision stable operation of magnetic suspension axial displacement is realized.

The invention provides hot-melt wave-absorbing resin, a low-frequency wave-absorbing prepreg and application of the hot-melt wave-absorbing resin and the low-frequency wave-absorbing prepreg in a low-broadband magnetic wave-absorbing composite material. The hot-melt wave-absorbing resin is prepared from the following raw materials: hot-melt resin and a composite absorbent, the composition comprises a combination of a coupling agent modified conductive absorbent and a magnetic absorbent. The raw materials of the low-frequency wave-absorbing prepreg comprise the hot-melt wave-absorbing resin and reinforced fibers with low dielectric constant and low gram weight. The hot-melt wave-absorbing resin provided by the invention realizes the low-frequency wave-absorbing performance covering 1GHz. Through the synergistic effect of the conductive absorbent and the magnetic absorbent, the broadband wave-absorbing prepreg covering low frequency is prepared by using a hot melting method, the dielectric loss of the wave-absorbing prepreg is improved, and the low-frequency wave-absorbing performance is enhanced. And the formula can be changed according to frequency band requirements to meet the wave absorbing requirements of different frequency bands (from 0.3 GHz to 18GHz). According to the low-broadband magnetic wave-absorbing composite material with the wave-absorbing honeycomb provided by the invention, the wave-absorbing bandwidth coverage is expanded by 1-18 GHz.

The invention provides an L-band wave-absorbing material and a preparation method thereof, the wave-absorbing material comprises a Fe-Si-Al composite material, and the composite material is Fe-Si-Al soft magnetic particles with oxide layers formed on the surfaces; wherein the content of each element in the raw materials of the Fe-Si-Al soft magnetic particles is as follows: 84.5 to 85.5 weight percent of Fe, 9.5 to 10 weight percent of Si and 5 to 5.5 weight percent of Al; the diameter-thickness ratio of the Fe-Si-Al soft magnetic particle raw material is 50-100, and the average diameter of the Fe-Si-Al soft magnetic particle raw material is 20-40 [mu] m; and the thickness of the oxide layer is 5-12 nm. The wave-absorbing material disclosed by the invention has excellent low-frequency wave-absorbing performance and has the characteristics of being thin, light, wide and strong; the impedance matching Z of the wave-absorbing material is larger than or equal to 4, the minimum reflectivity of a product with the thickness being 5 mm is smaller than-10 dB within 1-2 GHz, and the wave-absorbing material can be suitable for being used under multiple wavelengths of the L wave band and meets the use requirement of the wave-absorbing material.

The invention relates to the technical field of crossing of geophysical exploration and artificial intelligence, and discloses a three-dimensional VSP data reconstruction method based on a three-dimensional blind sidewalk time frequency-space multi-domain interpolation network model, and the method comprises the steps: obtaining a to-be-reconstructed three-dimensional VSP data volume containing an irregular missing sidewalk; inputting the three-dimensional VSP data volume into a trained three-dimensional space-time-frequency mixed domain convolutional network model; performing down-sampling on the input data through an encoder to extract initial spatial-temporal characteristics; inputting the initial spatiotemporal features into a residual spatiotemporal-frequency wavenumber domain joint convolution feature fusion module to obtain fusion features; and inputting the fusion features into a decoder, and reconstructing a complete three-dimensional VSP data volume through up-sampling operation. According to the invention, through joint learning of ground seismic data (providing a macrostructure) and illuminance data (providing a physical propagation path), a reconstruction result with a reasonable geologic structure and extremely high fidelity of wave field features can be generated.

The device for separating good and bad seeds using resonant frequencies includes several key components: a lifting unit(7) with a seed inlet, outlet, and bucket elevator to transport seeds vertically into an air tunnel(11); an air tunnel with an air blower to separate light waste from heavier seeds; a screening device(14) with holes to sort seeds based on size or shape; a divider(15) that disperses seeds using an air stream over a grooved shaft; a low-frequency wave transmitter that vibrates the seed collection; and a high-frequency wave transmitter with piezoelectric elements connected to a frequency generator and amplifier. The screening device is designed to separate seeds based on size, and the low-frequency transmitter uses a diaphragm to convert electrical signals into sound waves. The separation surface features at least two jacks for adjusting its slope, helping control the seed ejection path.

The invention discloses an oil abrasive particle detection device based on pseudo-random signal excitation and an inversion method, a pseudo-random excitation module outputs pseudo-random alternating current excitation formed by combining a plurality of waveforms, and the pseudo-random waveforms are not less than three frequency waveforms; the sensing module is a three-coil balance type, double-coil mutual inductance type or single-coil self-inductance type inductance sensing unit, coils in the sensing module construct a detection area with an alternating magnetic field under the excitation of alternating current, and the alternating magnetic field has pseudo-random characteristics; the signal acquisition and fitting module detects an induced voltage signal of the coil, and signal pulses generated by the metal abrasive particles under different excitation waveforms are obtained through fitting according to pseudo-random alternating current excitation characteristics; and the abrasive particle feature inversion module performs inversion according to the abrasive particle pulse signals generated by fitting under each excitation, and calculates the equivalent radius, the conductivity and the magnetic conductivity corresponding to the abrasive particles, so as to determine the material and the size of the abrasive particles. According to the invention, the material, size and concentration information of the abrasive particles can be accurately obtained.

The invention provides a frequency-wavenumber domain-based matrix array full-matrix capture three-dimensional ultrasonic imaging method and system, and belongs to the technical field of ultrasonic imaging. Five-dimensional time-space domain radio frequency data are collected through a two-dimensional full-sampling matrix array and are converted into a frequency-wave number domain through five-dimensional fast Fourier transform, angular frequency is mapped into axial wave number through Stolt interpolation, data resampling is achieved, then three-dimensional image frequency spectrum data are synthesized by defining spatial wave number coordinates of an image and conducting coherence stacking, and the image frequency spectrum data are obtained. And finally, reconstructing a high-quality three-dimensional ultrasonic image through three-dimensional inverse fast Fourier transform. Compared with a traditional delay summation beam forming method, the method has the advantages that the calculation efficiency is remarkably improved, the speed is increased by several times to dozens of times, the spatial resolution, the contrast noise ratio and the spot signal-to-noise ratio are remarkably improved, and the method is suitable for high-resolution real-time three-dimensional and four-dimensional ultrasonic imaging application.

The invention relates to a Lamb wave frequency dispersion characteristic sparse reconstruction method based on non-convex optimization, and belongs to the technical field of high-end equipment perception and test.The method comprises the steps that excitation is conducted on a U-shaped suspension arm, and time domain sampling signals at the junction of a U-shaped suspension arm structure are obtained; the time domain sampling signals are preprocessed; constructing a non-convex sparse frequency dispersion curve estimation model based on the preprocessed signal; and converting the non-convex sparse frequency dispersion curve estimation model into an optimization problem, searching a convex preserving condition of a target function, selecting a forward and backward splitting algorithm for solving, obtaining frequency-wave number distribution, and further extracting a frequency dispersion curve. The method solves the problems that a traditional convex regularization method is limited in induction sparse capability and underestimates signal amplitude. Through a non-convex optimization method, the purpose of accurate estimation of the frequency dispersion curve based on fewer measurement points is achieved.

In an example of an embodiment, a plasma processing apparatus includes a processing container, a stage, an upper electrode, an inlet, and a waveguide device. The stage is provided within the processing container. The upper electrode is provided above the stage, to interpose a space within the processing container. The inlet is configured to introduce high-frequency waves. The high-frequency waves are VHF waves or UHF waves. The inlet is provided at an end of the space in the lateral direction, and extends in a circumferential direction around a central axis of the processing container. The waveguide device is configured to supply high-frequency waves to the inlet. The waveguide device includes a resonator that provides a waveguide. The waveguide of the resonator extends in the circumferential direction around the central axis and extends in the direction in which the central axis extends to be connected to the inlet.

This invention relates to a method for extracting guided wavenumbers in variable thickness structures, belonging to the field of nondestructive testing technology. It utilizes an excitation signal to generate guided wave signals on the surface of the object under test. Based on a set window function and a set window length, the two-dimensional wavefield signal obtained by sampling the guided wave signal is divided into multiple local wavefield signals. A short-space Fourier transform is then performed on each local wavefield signal to obtain the amplitude-frequency-wavenumber array corresponding to each local space. A frequency range is then selected by summing the amplitude-frequency-wavenumber arrays of each local space, using the center frequency of the excitation signal as the midpoint. The weighted average wavenumber of each frequency point within the selected frequency range is calculated using the amplitude corresponding to the wavenumber sequence at each frequency point as the weight. The mean of the sum of the weighted average wavenumbers at each frequency point is then used as the wavenumber corresponding to the center position of each local signal space, and these values ​​are sequentially spliced ​​to obtain the wavenumber curve of the guided wave signal. This method solves the problem in existing technologies where the obtained guided wavenumbers cannot accurately reflect the thickness changes of variable thickness structures.

The application discloses a space-time-frequency wave number domain synchronous extrusion superimposed dense channel reservoir characterization method, which comprises the following steps: S1, inputting original seismic data s(t, x) to be analyzed, wherein x is the number of channels, and t is time; S2, obtaining short-time Fourier transform V2(t, x, omega, k) of the signal by using a Gaussian window function g(t, x), wherein omega is frequency, and k is wave number; S3, calculating an instantaneous frequency and an instantaneous wave number estimation of the signal according to S2; S4, defining an extrusion operator TDSTO according to S3; S5, constructing a space-time-frequency wave number domain synchronous extrusion transform characterization method TDSST(t, omega, x, k) according to the extrusion principle; S6, fixing the wave number by maximizing the energy of TDSST, so as to obtain a TDSST time-space-frequency domain three-dimensional data body TDSST(t, x, omega, k(t, x, omega)); and S7, performing feature extraction of frequency f0 in S6, so as to obtain a single-frequency profile to characterize the morphological structure characteristics of a complex superimposed dense channel sandstone reservoir. The application can provide a space-time reservoir morphological characterization method considering the lateral characteristics of a complex superimposed dense channel sandstone.

The invention provides an elastic wave CT (Computed Tomography) signal denoising method for improving the inversion precision of karst cave exploration, which belongs to the technical field of engineering exploration and comprises the following steps of: performing normalization preprocessing on a received signal, suppressing random noise by adaptive filtering, converting a time domain signal into an F-K domain and identifying a surface wave, filtering a surface wave signal by a Gaussian band elimination filter, and converting the F-K domain signal back to the time domain. The method comprises the following steps of: highlighting a take-off characteristic of a weak P wave covered by a strong surface wave through normalization; using a minimum mean square error adaptive filter to accurately filter random noise; subsequently converting to an F-K domain, and smoothly attenuating the surface wave through a Gaussian band elimination filter by utilizing the frequency wave number distribution difference of the surface wave and the P wave; the method realizes layered removal of random noise and surface waves, finally outputs high-purity direct P-wave signals, greatly improves P-wave travel time pickup and wave velocity calculation precision, and remarkably improves inversion precision of an elastic wave CT exploration method in detection of geologic bodies such as karst caves and fracture zones.

The invention discloses a ship identification method and system based on dual physical model fusion verification, and relates to the technical field of optical fiber sensing and ocean monitoring. The method aims at solving the problems that ship noise in submarine optical cable DAS signals is prone to interference of environment noise such as low-speed guided waves, the false alarm rate is high, and accurate positioning cannot be achieved. The method comprises the steps that DAS phase data is acquired and preprocessed to generate a channel-time energy diagram; suppressing low-speed guided wave noise through frequency-wavenumber domain slowness scanning, detecting an energy ridge line on the purified energy diagram, and calculating an observation apparent velocity; acquiring AIS data to calculate and predict the apparent velocity; the relative error of the observed apparent velocity and the predicted apparent velocity is firstly matched, and then linear regression is carried out on the arrival time of the candidate ridge line and the AIS distance to verify and fit the root mean square error; the validated ridge line is confirmed as an effective ship event and a directory is generated. According to the technical scheme, through physical mechanism denoising and dual model verification, the accuracy and reliability of ship identification are effectively improved.

The application discloses a control method and system of a three-phase three-level AC / DC converter. A multiple parallel quasi-resonant PR control method based on time delay phase compensation is adopted in the main control link of the application, the time delay is converted into a fixed phase which needs to be compensated for the fundamental wave and high-order, and the influence of the delay between sampling and output on the system is improved. In view of the frequency fluctuation of the power grid, the real-time frequency of the power grid is updated in real time through a DSOGI-FLL, and the frequency value is transferred to the phase compensation link. The compensation link calculates through the new frequency value, obtains a new transfer function after calculating new parameter values, is connected in series into the main control link, and the effect of adaptive adjustment is realized.

The invention relates to a low-voltage cable fault diagnosis positioning method and device based on stepping frequency wave reflection. The low-voltage cable fault diagnosis and positioning method based on stepping frequency wave reflection comprises the following steps: inputting a stepping frequency signal to a first end of a cable, and receiving a reflection signal of the stepping frequency signal; establishing an equivalent parameter model of the to-be-detected cable; calculating a reflection coefficient L of the first end according to the equivalent parameter model and the reflection signal; judging whether the cable has a fault according to the L; if gamma is equal to 0, the cable is healthy, and if gamma is not equal to 0, the cable has a fault; and determining the fault distance according to the time difference between the step frequency signal and the reflection signal. By injecting the detection signal into the to-be-detected cable and extracting the reflected wave, local insulation damage of the low-voltage cable can be effectively detected, potential fault points can be found in time, accidental power failure and accidents caused by insulation damage can be prevented and reduced, and the safety of a power grid is improved.

The application relates to a vibration energy collecting device and a working platform, which comprises a shell, a power capturing mechanism arranged in the shell, the power capturing mechanism comprising a power capturing magnet capable of moving up and down, and a transducing mechanism arranged in the shell, the transducing mechanism comprising a transducing support, a transducing magnet arranged in the transducing support and a coil arranged outside the transducing support, when the power capturing magnet moves relative to the shell, the transducing magnet flips relative to the transducing support, and the angle difference between the extending direction of the flipping axis of the transducing magnet and the moving direction of the power capturing magnet is less than or equal to 45 degrees. The vibration energy collecting device has simple structure, and through the mutual attraction between the power capturing magnet and the transducing magnet and the reciprocating motion of the power capturing magnet, the high-frequency flipping of the transducing magnet is realized, so that the conversion from low-frequency wave excitation to high-frequency alternating current is realized.

A cooking apparatus includes a cooking chamber, a heating source disposed below the cooking chamber to produce high-frequency waves, a main plate forming at least a portion of the cooking chamber and including a front side which is opened, a front plate coupled to the front side of the main plate and including a base having an opening connected to the cooking chamber, and a front coupling flange. The front coupling flange is bent rearward from an inner end of the base, coupled by curling with the main plate, and has a portion which protrudes above a lower surface of the main plate.

The invention relates to the technical field of radar detection and application thereof, and provides a data processing method for ground penetrating radar data, which comprises the following steps: firstly, carrying out preprocessing and gain recovery on original radar data, then carrying out mixed denoising by adopting empirical mode decomposition and Wiener filtering, screening and reconstructing effective signals by utilizing cross correlation coefficients, and finally, carrying out data processing on the effective signals. The method comprises the following steps: firstly, constructing a filter in a frequency wave number domain to remove random noise and low-frequency interference, then constructing a fan-shaped filter in the frequency wave number domain, introducing transition band processing to suppress linear coherent interference, then carrying out wave velocity estimation based on an image entropy minimization criterion to obtain an optimal imaging wave velocity, and finally executing Stolt migration imaging by using the optimal wave velocity and outputting a result. According to the method, edge details of effective signals are effectively reserved through multi-scale decomposition, the problem of imaging defocusing is solved through self-adaptive wave velocity search, and the signal-to-noise ratio, the resolution ratio and the focusing precision of ground penetrating radar data in a complex and strong-interference environment are remarkably improved.

The application discloses a radar complementary sparse frequency waveform sequence set design method based on a complex circle flow surface algorithm, and specifically comprises the following steps: according to a monitored spectrum environment, delimiting a usable spectrum range and an unusable spectrum range; converting a weighted integral sidelobe level of a waveform sequence set into a quadratic function form with a waveform sequence set vector as a variable, constructing an objective function to describe the weighted integral sidelobe level of the waveform set; calculating a power spectrum of the waveform set, controlling a weighting coefficient according to an expected spectrum, performing weighted summation on the power spectrum, and converting a weighted summation expression of the power spectrum into a quadratic function form with the waveform sequence set vector as the variable; and performing weighted summation on a WISL objective function and an EFS objective function to construct a joint objective function. The CCM optimization algorithm is applied to the complementary sparse frequency waveform sequence set design problem for the first time, effectively solving the constant modulus constraint problem of the waveform sequence, and compared with the existing cyclic iteration algorithm and the interior point method.

The application discloses a low-frequency broadband sound absorber, which comprises a resonator, the outer part of the resonator is covered with a porous material layer, one side of the porous material layer is connected with a rigid backing, and the side opposite to the rigid backing is an incident surface; the resonator comprises an inner shell and an outer shell, the inner shell is located inside the outer shell; a first opening is arranged at the center of one side of the outer shell close to the sound wave incident surface, a second opening is arranged at the center of one side of the inner shell close to the rigid backing, and the first opening and the second opening are oppositely arranged. The application can efficiently absorb sound waves in a wide band range of low-frequency waves, and the high-efficiency absorption effect is hardly affected by the sound wave incident angle.

The invention provides a high-frequency harmonic suppression method, device and equipment for vacuum circuit breakers and a storage medium, each vacuum circuit breaker is provided with a high-frequency harmonic damper, and the method comprises the following steps: collecting power grid voltage and current signals of each vacuum circuit breaker in a preset area, and determining a harmonic state vector according to the power grid voltage and current signals; based on a preset multi-agent environment, calculating a first admittance value of a connected harmonic damper according to the harmonic state vector, and determining a damping action instruction according to the first admittance value; performing multi-round iteration on the damping action instruction according to a preset distributed collaborative architecture to obtain an execution instruction, the execution instruction comprising a second admittance value; modulating a driving signal of the high-frequency harmonic damper according to a second admittance value of the execution instruction so as to enable the high-frequency harmonic damper to output a high-frequency wave blocking signal; and inputting the high-frequency wave-blocking signal into the vacuum circuit breaker to reduce the high-frequency harmonic wave of the vacuum circuit breaker.

The application discloses a kind of lining demolition operation in geological anomalous body detection method and signal processing method, first, by being arranged in the lining inside and the cutting route parallel two detection lines in multiple detectors, vibration signal between cutting disc and concrete lining in the lining cutting operation process is acquired in real time, and vibration signal obtained in real time is handled.Then, the vibration signal after processing is carried out two-dimensional fast Fourier transform, and the frequency-wave number spectrum corresponding to vibration signal is obtained.Afterwards, dispersion curve and reflected wave signal are extracted from the frequency-wave number spectrum.Finally, dispersion curve is carried out interference wave inversion, and the shear wave velocity spectrum inside the geological body behind lining is obtained, and reflected wave signal is inverted and imaged, and the reflected interface image inside the geological body behind lining is obtained.Combining reflected interface image and shear wave velocity spectrum can accurately locate the anomaly of the geological body behind lining, and effectively detect the geological body anomaly behind existing lining.

The application discloses a wave compensation system and method for umbilical cable deployment of engineering ships, and belongs to the technical field of umbilical cable tension control. The system comprises a winch mechanism, a cable arrangement mechanism, a compensation mechanism and a detection and control unit. The compensation mechanism adopts a double-layer parallelogram winding structure composed of four pulleys, and the path length of the umbilical cable is changed by driving the pulley frame to move through a linear composite oil cylinder. The system adopts a hybrid compensation strategy combining passive compensation and active compensation. The passive compensation utilizes the energy storage characteristics of the accumulator to achieve rapid response to high-frequency wave disturbance, and the active compensation realizes compensation accuracy correction through feedforward control and feedback control. The controller monitors the pulley displacement and controls the winch to wind or unwind the cable when the threshold is exceeded, thereby expanding the effective compensation range of the system. The cable arrangement mechanism and the winch are synchronized to ensure that the umbilical cable is uniformly arranged on the drum. The application realizes stable umbilical cable tension in complex sea conditions, and provides a more reasonable solution for underwater deployment.

The invention discloses a broadband oscillation suppression method of a wind power flexible direct current transmission grid-connected system, and relates to the technical field of broadband oscillation suppression of a power system, and the method comprises the steps: firstly, recognizing the frequency information of broadband oscillation according to a multi-frequency oscillation frequency online recognition link; then, designing a multi-band wave trap by adopting a windowing orthogonal matching pursuit (OMP) algorithm; and finally, providing a real-time center frequency for the multi-frequency wave trap according to a frequency identification link so as to realize broadband oscillation self-adaptive suppression. According to the method, the time-varying oscillation frequency can be effectively tracked through an online identification algorithm, so that the method adapts to oscillation scenes under different system working conditions. The windowing OMP method provided by the invention can avoid the problem that the coefficient of the wave trap needs to be redesigned when the center frequency of the wave trap changes, reduces the calculation amount, improves the real-time performance of the algorithm, and achieves the self-adaptive suppression of broadband oscillation.

A method for modeling a subterranean volume includes receiving seismic data comprising a signal, generating a semblance in the frequency-wavenumber domain for the seismic data, wherein the semblance represents a coherence of the signal in the frequency-wavenumber domain, extracting one or more wave energy modes in the semblance using a machine learning model trained to identify dispersion curves in the semblance based on a visible characteristic of the dispersion curves, and generating a model representing surface wave propagation based at least in part on the identified one or more wave energy modes.

This application relates to the field of wearable device technology, and more particularly to a wearable device. The wearable device body includes a housing, a screen assembly, a motherboard, a functional module, and an elastic wave receiving unit. At least one of the screen assembly and the housing is configured to deform under user operation to generate elastic waves. The elastic wave receiving unit is configured to receive the elastic waves and generate an elastic wave signal. The motherboard is configured to control the functional module to perform corresponding functions when the elastic wave signal matches a target elastic wave signal. The wearable device of this application, by utilizing the elastic wave receiving unit to achieve functional control of the wearable device, not only facilitates user operation but also, because elastic waves are low-frequency waves with high energy and long wavelengths, have strong anti-interference capabilities, thereby improving signal transmission reliability. Furthermore, it eliminates the need for additional openings in the wearable device, thus reducing the difficulty of waterproofing and effectively improving the waterproofness of the wearable device.