387 results about "Wave speed" patented technology

The invention relates to the technical field of power distribution network fault positioning, in particular to a power distribution network fault positioning method based on traveling wave detection, and the method comprises the following steps: S1, distributed detection network construction and signal collection: collecting a three-phase current traveling wave signal in real time; s2, time-frequency joint analysis and feature extraction: extracting time-frequency energy distribution features; s3, intelligent screening of effective fault wave heads: screening out the effective fault wave heads; s4, initial arrival time parameter determination: determining the initial arrival time of each detection point; s5, according to topology self-adaptive error correction, transmission path wave velocity deviation is corrected through line parameter dynamic compensation, and clock errors of the asynchronous detection device are eliminated through adjacent node clock difference estimation; and S6, multi-source data fusion and fault positioning: resolving space coordinates of fault points. According to the invention, the method improves the recognition accuracy of fault features, and solves the problems of poor anti-interference capability and high misjudgment rate of a single feature in a conventional method.

The invention relates to a transverse isotropic hard formation horizontal shear wave velocity inversion method and device. The method comprises the following steps: acquiring waveform data measured by a target interval array acoustic logging dipole mode; based on the waveform data, using a weighted spectrum coherence analysis method to calculate and obtain a bending wave actual measurement frequency dispersion curve; according to the bending wave actual measurement frequency dispersion curve, calculating to obtain bending wave time difference probability density; according to the bending wave time difference probability density, calculating to obtain a stratum vertical shear wave speed; establishing an objective function of transverse isotropic stratum horizontal shear wave velocity inversion based on a frequency dispersion equation of the transverse isotropic stratum and the stratum vertical shear wave velocity; and according to the objective function, inversion is carried out to obtain the stratum horizontal shear wave velocity. According to the method, the target function of horizontal shear wave velocity inversion is reduced from two dimensions to one dimension, and the stability and efficiency of inversion are remarkably improved.

The invention relates to the technical field of power systems, and discloses a distribution line fault positioning method and system based on traveling wave distance measurement. The method comprises the following steps: injecting a zero-mode signal through an electrified pulse coupler, carrying out wave velocity hierarchical analysis on a mixed line impedance node to obtain a propagation parameter matrix, generating an empty-mode echo by utilizing mode conversion of a fault asymmetric point, screening by adopting a frequency domain fingerprint identification algorithm to obtain a pure fault signal, and carrying out fault detection on the pure fault signal. And three-dimensional fault coordinates are obtained based on reverse time-distance mapping processing. According to the invention, the problem of accurate positioning of the fault point in the live-line operation state of the hybrid distribution line is solved, and the fault positioning accuracy and the power supply reliability are improved.

The invention discloses a micro-seismic multichannel data processing method and system based on a DBSCAN algorithm, and belongs to the technical field of micro-seismic monitoring. According to the invention, through feature vector construction and optimization distance calculation, the clustering reliability is enhanced; a multi-dimensional feature vector Xi containing P-wave refinement arrival time ti, an amplitude Ai and space coordinates (xi, yi, zi) is constructed, distance calculation is performed by combining a normalized cosine distance with wave velocity constraint, a micro-seismic wave propagation rule is fully utilized, the discrimination capability of DBSCAN clustering on physical consistency is enhanced, and the robustness of a screening result is improved, so that noise interference can be effectively processed in a complex environment, and the accuracy and the robustness of the screening result are improved. And the stability and the reliability of a micro-seismic positioning result under different geological conditions are ensured.

The invention discloses a power grid fault positioning system and method based on traveling wave distance measurement, relates to the technical field of fault analysis, and solves the technical problems that traveling wave feature analysis, temperature compensation and high-precision synchronization technologies are not effectively integrated, and rapid and accurate fault positioning of a smart power grid is difficult to meet. Through the technical combination of dynamic temperature compensation, high-precision time synchronization and intelligent fault classification, the bottlenecks of traditional traveling wave distance measurement in the aspects of precision, reliability and intelligence are systematically solved, temperature sensors are deployed at key nodes of a cable, the temperature is monitored in real time, the wave speed is dynamically corrected through a formula, the overall error is reduced, and the fault location accuracy is improved. Meanwhile, an optical fiber two-way time transmission method is combined, transmission delay errors are reduced, synchronization reliability is improved, finally, a mapping library is constructed through laboratory simulation and field data, a Euclidean distance matching algorithm is combined, fault reasons are automatically recognized, and rapid positioning of the faults and accurate recognition of the fault reasons are achieved.

The invention discloses an underground space surrounding rock excavation damage area testing method, which belongs to the technical field of rock mass damage testing, and comprises the following steps: sampling rocks with different depths, carrying out ultrasonic testing, and determining rock sample attenuation characteristics and wave velocity; determining a comprehensive damage index range of the rock samples with different damage grades; then, sensors are arranged in the excavation process to collect ultrasonic and acoustic emission data; then, an initial calculation model is constructed, and a surrounding rock three-dimensional wave velocity model is obtained through inversion of collected data; and finally, determining a damage grade according to the comprehensive damage index, and marking in the model to realize damage area testing. According to the method, the mapping relation between the damage degree and the wave velocity change is established, the comprehensive damage index range threshold value of different subareas is provided, quantitative and gradable classification is achieved, the three-dimensional wave velocity model is inversed based on test and monitoring data, and three-dimensional presentation and grading labeling of the damage area are achieved.

The invention discloses a traveling wave fault location improvement method for power distribution network fault location analysis, relates to the technical field of power distribution networks, and solves the problems that a traditional single wave velocity model causes location deviation, and particularly, false fault points are easily generated at the joint of a cable and an overhead line due to refraction and reflection. And calculating an amplitude difference mean value under different translation amounts, automatically identifying an optimal time alignment point, and locking an association time difference t1. According to the process, time errors caused by signal distortion, asynchronous sampling and the like can be effectively corrected, the time difference precision is improved from the microsecond level to the nanosecond level, a foundation is laid for follow-up precise positioning, a plurality of correlation points are randomly selected in a locked range interval, a corrected waveform is constructed based on the attenuation proportion and repeated verification is carried out, and the time difference precision is improved. Screening an optimal solution through a feature mean value minimization algorithm; the mechanism can effectively inhibit the error of a single measuring point, and improves the robustness of a positioning result through the statistical average effect.

The invention relates to the technical field of discharge monitoring and early warning, in particular to a partial discharge real-time monitoring and early warning system based on multi-source data fusion, which is characterized in that decision tree classification is carried out on a mixed transient signal flow through a signal physical separation module, and pure electromagnetic wave speed type and mechanical wave speed type signal sources are separated; the feature marking module extracts feature points with a unified time reference and marks physical attribute categories; the double-path credibility fusion module executes time difference logic verification on the two types of feature points, a credible discharge event is marked only when an electromagnetic wave verification result and a mechanical wave verification result are logic values 1 at the same time, event confidence parameters are generated through dynamic confidence fusion, and physical interlocking verification and uniqueness locking are achieved; the anti-interference response module dynamically adjusts a response threshold value based on the event confidence parameter, and only triggers a targeted response to the threat which is physically and essentially confirmed to be real discharge and has confidence reaching the standard; the problem of distinguishing a real discharge event from multi-source interference is solved, and the real discharge event is reliably identified.

The invention discloses a side slope wave velocity change measurement method based on passive source space superposition. The method comprises the following steps: preprocessing original seismic data of a seismic station; calculating a nine-component cross-correlation function between the station pairs; cross-correlation is taken as reference cross-correlation in five days before superposition; calculating a signal-to-noise ratio between a cross-correlation function tail wave and reference cross-correlation, extracting a tail wave signal with a relatively high signal-to-noise ratio for each component, and measuring wave velocity change through a straining method; dividing different sub-station network areas according to station layout, and superposing wave velocity changes obtained by each tail wave on different components of different rays; carrying out thermoelastic strain correction on the wave velocity change to obtain a wave velocity change diagram; calculating response coefficients of seismic waves with different frequencies at different depths; and obtaining an underground medium four-dimensional wave velocity change graph. According to the invention, new technical means and scientific basis are provided for constructing an underground shallow internal wave velocity change real-time monitoring system and researching and preventing landslide geological disasters.

The invention discloses a tunnel micro-seismic enhanced positioning method and system based on a DAS and a blasting active source signal. The method comprises the steps that firstly, optical fibers are arranged on the surface of a tunnel wall and in a drill hole; blasting the tunnel face to generate a blasting active source signal with known time and space; then, a blasting active source signal is collected through a DAS system, and P wave arrival time of each monitoring point on the optical fiber is recorded; establishing and optimizing a wave velocity field partition model according to the spatio-temporal information of the blasting active source signal and P wave arrival time of each monitoring point on the optical fiber; and when a micro-seismic event occurs in the surrounding rock, the optimized wave velocity field partition model and P wave arrival time measured at each monitoring point on the optical fiber are utilized, a geometric algorithm is combined to invert and position the micro-seismic event, and a positioning result is output. The system comprises a signal acquisition system, an optical fiber network and a DAS system. The method has the advantages that the wave velocity field model is optimized and dynamically updated by using the tunnel face blasting signal, and the distributed sensing is performed by using the DAS system, so that the capability of monitoring and evaluating the micro-seismic event of the tunnel is remarkably enhanced.

The invention relates to the technical field of earthquake monitoring, and discloses a comprehensive earthquake prediction method, which comprises the following steps of: acquiring a continuous micro-motion data sequence to reconstruct an empirical green function sequence, and dividing the empirical green function sequence into a compression phase subset and a stretching phase subset by utilizing a synchronously acquired theoretical earth tide stress phase; respectively extracting a causal branch waveform corresponding to the positive time axis and a non-causal branch waveform corresponding to the negative time axis, and determining a weight index for inhibiting the non-structural interference by calculating a reciprocity residual error between a causal wave velocity offset and a non-causal wave velocity offset; correcting a wave velocity offset mean value by using the weight index to obtain a stress sensitivity coefficient reflecting the stress state of the earth crust medium; according to the method, a physical criterion is established by using an elastic wave propagation reciprocity principle, decoupling of medium attribute change and noise source spatial drift is realized, and visual wave velocity offset induced by environmental interference is eliminated.

The invention discloses a cable defect detection method and device, and relates to the field of power equipment fault detection, and the method comprises the steps: generating N electric signals with different frequencies in a preset frequency range, inputting the electric signals into a target cable, testing the input impedance of the target cable under the N electric signals with different frequencies, the broadband impedance of the target cable in the frequency range is obtained; according to the broadband impedance, generating an impedance amplitude and an impedance phase of the target cable at each preset frequency point, and constructing an impedance matrix; inputting the impedance matrix into a fault classification model, and identifying and outputting the category of the target cable through the fault classification model; and if the target cable has a fault, extracting the resonant frequency with the maximum amplitude in the broadband impedance amplitude spectrum of the target cable, and determining the fault position of the target cable through a fault positioning model according to the resonant frequency with the maximum amplitude and the typical wave velocity of the target cable. According to the invention, the fault of the target cable can be automatically, quickly and accurately identified, and the fault position can be positioned.

The invention relates to the technical field of wireless communication, and discloses an information source number detection method and system based on a non-circular signal. The method comprises the following steps: calculating a compensation sample covariance matrix of a received signal, and obtaining a sample canonical correlation coefficient through Takagi decomposition of the compensation sample covariance matrix; constructing a marginal likelihood function of the maternal typical correlation coefficient; taking a sample canonical correlation coefficient as an estimated value of a corresponding matrix, and establishing an estimated statistic by applying a minimum description length criterion; and obtaining the number of the parent typical correlation coefficients when the estimation statistic is minimized, and taking the number as an estimation value of the actual number of the non-circular signals. According to the method, the characteristic that the non-circular signal compensation covariance is not zero is fully utilized, the marginal likelihood function with the minimum redundancy parameters is adopted to construct the statistics, high-precision estimation of the number of the non-circular signals can be achieved, and necessary guarantee is provided for practical application scenes such as direction of arrival estimation and wave velocity formation.

The invention belongs to the technical field of mine safety monitoring and rock mass engineering detection, and particularly discloses a method for constructing a non-uniform wave velocity field model of an underground mine, which comprises the following steps: selecting a plurality of rock materials, manufacturing a plurality of regular blocks, measuring a reference wave velocity, manufacturing a rock test piece, and carrying out a wave velocity test experiment; a wave velocity quantification formula is constructed through fitting experiment data; constructing a three-dimensional block model according to the spatial features of the prediction area, dividing the three-dimensional block model into a plurality of block unit models, and generating a lithologic block unit model through spatial interpolation; and constructing a three-dimensional engineering geological representation model, extracting geological feature data in the three-dimensional engineering geological representation model, and performing wave velocity assignment on all lithologic block unit models by using a wave velocity quantification formula to obtain a three-dimensional non-uniform wave velocity field model. According to the method, the wave velocity field model better conforming to the actual condition of the underground mine can be constructed, the limitation of constant wave velocity assumption in a traditional model is overcome, and the reliability of micro-seismic monitoring is improved.

The invention discloses a wave velocity testing module, and a device and a method for simultaneously testing the wave velocity and CPTU of a soil body. The wave velocity testing module comprises a wave velocity testing module shell, a wave velocity measuring module and a wave velocity measuring module, the energy converter is used for converting the electric energy into sound energy and converting the sound energy into an electric signal at the same time; the adhesive layer is arranged in the space of the wave velocity testing module shell between the transducer and the reflecting plate; and the reflecting plate is arranged in the wave velocity testing module shell, is obliquely arranged above the energy converter, and is used for changing the sound wave emitted by the energy converter to be propagated in the direction perpendicular to the outer wall of the wave velocity testing module shell, receiving the reflected sound wave reflected by the soil body, changing the direction of the reflected sound wave and then transmitting the reflected sound wave to the energy converter. According to the device, CPTU testing and wave velocity testing can be completed at the same time in the one-time penetration process, multiple soil mass mechanical properties and acoustic parameters can be tested through one-time penetration of one set of equipment, the testing work efficiency is improved, and the testing result precision is more accurate.

A mixed traffic flow-oriented vehicle eco-driving control method and an electronic device are provided. The method includes: calculating a gathering wave speed and a dissipation wave speed at an intersection, and obtaining a farthest queue point position of a connected and autonomous vehicle at a downstream intersection and a time, acquiring predicted trajectories of the manual-driving vehicle; constructing and solving an optimal ecological reference trajectory planning model of the connected and autonomous vehicle, obtaining an acceleration curve of the connected and autonomous vehicle, and acquiring an ecological reference trajectory of the connected and autonomous vehicle; and setting a risk factor based on the predicted trajectories of the manual-driving vehicles, constructing a tracking target based on the risk factor and the ecological reference trajectory, using a model predictive control for solving, and obtaining a control input of the connected and autonomous vehicle.

The invention provides a roadway surrounding rock dynamic deformation prediction method and device, equipment and a storage medium, and the method comprises the steps: carrying out the feature extraction of the dynamic data parameter information of the roadway surrounding rock, so as to determine the propagation speed change information of a stress wave in the surrounding rock and the instantaneous strain change rate of the surrounding rock under dynamic loading; determining a wave velocity change index according to the propagation velocity change information of the stress wave in the surrounding rock; determining an instantaneous deformation strain rate index according to the instantaneous strain change rate of the surrounding rock under dynamic loading; inputting the wave velocity change index and the instantaneous deformation strain rate index into a pre-trained machine learning model to generate a surrounding rock deformation index; and performing surrounding rock change state evaluation based on the surrounding rock deformation index. By implementing the method disclosed by the invention, the influence of instantaneous stress wave propagation caused by dynamic loading on the surrounding rock can be effectively combined in the dynamic deformation prediction process of the roadway surrounding rock, so that the accuracy and practicability of a dynamic deformation prediction result of the surrounding rock are effectively improved.

The invention provides a Prony algorithm-based cable segment wave velocity acquisition method, device and system, and a medium, and the method comprises the steps: testing a to-be-tested cable, and obtaining a cable signal transfer function; on the basis of the cable signal transfer function, in combination with cable joint distribution, constructing a cable signal approximation function based on a Prony method; constructing a linear prediction model of the cable signal based on the cable signal approximation function; performing denoising processing on the linear prediction model based on a singular value decomposition method to obtain a denoised linear prediction model; solving the denoised linear prediction model to obtain an attenuation coefficient; and calculating the segmented wave velocity of the cable based on the attenuation coefficient. According to the method, the Prony estimation method is combined with the singular value decomposition noise reduction algorithm, high-precision extraction of attenuation constants and segmented wave velocity decoupling are achieved, and then the electrical distance positioning precision is improved.

The invention discloses an inertial navigation underwater path tracking method and system for a complex marine environment, and relates to the technical field of inertial navigation. The method comprises the following steps of AUV navigation monitoring, underwater tracking position correction, underwater path tracking stability analysis and underwater path tracking stability change analysis. According to the method, the IMU acceleration change condition and the DVL wave velocity quality fluctuation condition in the INS are monitored, IMU acceleration change analysis and DVL wave velocity quality fluctuation analysis are carried out respectively, then an underwater tracking position correction scheme is decided based on the two analysis results, and underwater path position credibility analysis is carried out at the same time. And whether path stability correction measures are taken or not is judged according to the stability condition of underwater path position tracking of the AUV, and then whether path correction adjustment is executed or not is determined, so that the precision of the underwater path tracking position is improved, and the problem that the accuracy of the underwater path tracking position is reduced in the prior art is solved.

The invention relates to the technical field of speed reducers, and discloses a special wave speed reducer for a robot joint. A flexible gear is installed on an inner ring of the roller crossed bearing, a rigid gear is installed on the outer side of the flexible gear, a lubricating mechanism is installed on the inner wall, close to the flexible gear, of the rigid gear, a wave generator is installed in the flexible gear, the lubricating mechanism comprises a fixing ring, a through hole and a lubricating layer, and the fixing ring is installed on the inner wall, close to the flexible gear, of the rigid gear. Through cooperative use of the fixing ring, the through hole and the lubricating layer, lubricating oil in the fixing ring can be conveyed to the lubricating layer through the through hole, when the flexible gear rotates, the lubricating oil adsorbed on the lubricating layer can be directly smeared to the outer surface of the flexible gear, and the lubricating oil can gradually permeate between the flexible gear and the rigid gear; the transmission position of the outer surface of the flexible gear and the inner wall of the rigid gear is lubricated, so that abrasion of the speed reducer caused by lack of lubricating oil can be reduced, the internal temperature of the speed reducer is reduced, and work of the speed reducer is not affected.

The invention provides a system and a method for positioning a gas leakage part of a gas storage. The method comprises the following steps: emitting an optical signal to a first optical fiber arranged in the gas storage; the receiving point receives an optical signal which is changed due to the influence of ultrasonic vibration generated by the leakage point of the gas storage at the monitoring point; an optical signal which is changed due to the influence of ultrasonic vibration generated by a leakage point is converted into an electric signal; converting the electric signal into the length of the first optical fiber from the monitoring point to the receiving point; calculating position information of the monitoring point according to the length of the first optical fiber of the receiving point; calculating the wave velocity of ultrasonic waves; obtaining time differences of light signal changes of different monitoring points; and the position of the leakage point is calculated according to the position information of different monitoring points, the time difference of optical signal change of different monitoring points and the speed of ultrasonic waves. According to the invention, the detection accuracy and convenience can be improved.

The invention discloses an equivalent deformation modulus calculation method and system for a complex uneven rock mass and a medium. Relates to the technical field of rock engineering. The method comprises the following steps: partitioning according to geological information of rock masses and counting proportions, then respectively carrying out sound wave testing on the rock masses in different regions to obtain single-hole sound wave velocities, and calculating deformation moduli of the rock masses in each region by utilizing a correlation relationship between the single-hole wave velocities and the deformation moduli; a mixed equivalent model of strain coordination and stress coordination is constructed based on the rock mass strain energy proportion so as to calculate the equivalent deformation modulus of the special uneven rock mass; a new thought is provided for obtaining deformation modulus parameters containing multiple types of altered rocks, meanwhile, a targeted investigation and test scheme is provided, and an important basis is provided for design of rock mass slopes, caverns and the like.

The invention provides a surface wave information-based near-surface formation longitudinal wave velocity inversion method. The surface wave information-based near-surface formation longitudinal wave velocity inversion method comprises the following steps of: 1, extracting surface wave frequency dispersion data through a phase shift method; 2, according to the frequency dispersion curve, direct inversion is carried out to obtain the near-surface shear wave speed and thickness; step 3, calculating a W-D curve and a W / D-D curve; and 4, adding the W-D data and the W / D-D data into an objective function, and carrying out longitudinal wave velocity direct inversion. According to the near-surface formation longitudinal wave velocity inversion method based on the surface wave information, direct inversion of the near-surface formation longitudinal wave velocity can be achieved, information such as the transverse wave velocity, the formation thickness, the longitudinal wave velocity and the Poisson's ratio is obtained in the inversion process, and powerful research basis and support are provided for application of the surface wave information in oil exploration and engineering exploration.

The invention belongs to the technical field of rock-soil exploration, and provides a surface wave and body wave comprehensive exploration system and method based on a seismic source. The system comprises a seismic source device, the seismic source device comprises a seismic source and a driving control module, the seismic source is installed on a cutterhead and connected with the driving control module, a main control module is used for adjusting the seismic source to be supported on a tunnel face through the driving control module, and the seismic source is used for receiving an excitation instruction of the main control module and conducting seismic source excitation; the detector is linearly arranged on the earth surface along the tunneling direction of the shield tunneling machine and is used for acquiring a seismic source waveform signal; the main control module is used for preprocessing the seismic source waveform signal and separating a surface wave from a body wave; performing basis-high order joint inversion according to the separated surface wave data; obtaining a reflection imaging profile according to the separated body wave data; and obtaining a shear wave velocity profile and a stratum thickness according to basis-high order joint inversion, obtaining an underground wave velocity image based on a reflection imaging profile, and carrying out comprehensive identification on a target area by combining the two inversion results.

The invention discloses a cubic system single crystal turbine blade wall thickness ultrasonic detection method, which comprises the following steps: establishing a sound velocity model, carrying out wave velocity measurement on a standard sheet, and measuring an included angle omega between the vector direction of each wall thickness measurement point and a theoretical Y coordinate axis in a three-dimensional model, measuring a rotation angle alpha of a secondary dendritic crystal [100] of the part to be measured and a deviation angle theta between [001] orientation and a Z axis by adopting a Laue method or an XRD diffraction method, and substituting the included angle omega, the rotation angle alpha and the deviation angle theta of the Z axis into the sound velocity calculation model to obtain a real sound velocity of each wall thickness measurement point; and importing wall thickness data measured by the wall thickness gauge into a sound velocity model formula to obtain a corrected real wall thickness value. The method can solve the measurement error caused by anisotropy of the cubic system alloy, and has the advantages of high detection efficiency, low detection cost and the like.

The invention discloses a ring main unit cable line fault positioning system and method based on traveling wave intelligent sensing, and relates to the technical field of ring main unit cable line fault positioning, and the method comprises the following steps: arranging a traveling wave sensor at a position corresponding to a cable connecting plug or a solid-sealed polar pole in a ring main unit; an initial correction stage is carried out, a known electrical event is triggered on a cable in actual operation, the propagation time of a traveling wave signal between the two ends is measured, and the wave velocity of the traveling wave is actually measured on site and dynamically updated in combination with the known cable length; the method comprises the following steps: executing initial correction under different operation conditions, collecting corresponding data of working conditions and wave velocities, constructing a self-adaptive model of the wave velocities and working condition parameters, and when a fault occurs, dynamically predicting the wave velocities based on the constructed model according to current working condition parameters monitored in real time; and on the basis of the identified wave head timestamp, constructing an overdetermined equation set and solving an optimal fault position, so that the cable line fault positioning of the ring main unit is realized.

The invention discloses a rock mechanics dynamic-static conversion model construction method without damaging a rock core, equipment, a medium and a product, and relates to the field of rock mechanics, a group of rock samples are obtained, each rock sample is regarded as being composed of different sub-samples, the wave velocity and the volume density of each sub-sample meet normal distribution, and the wave velocity and the volume density of each sub-sample meet normal distribution; the standard deviation and the expected value are determined by the wave velocity and volume density experimental values of the group of rock samples. Substituting the wave velocity and the volume density of each generated sub-sample into a rock mechanical parameter physical model, calculating static mechanical parameters and dynamic mechanical parameters of the rock sample, and constructing a dynamic-static conversion model; performing stratigraphic section rock mechanical property analysis according to the dynamic-static conversion model; the rock mechanical parameter physical model is a theoretical relationship between the mechanical parameters of the rock sample and the mechanical parameters of each sub-sample. The dynamic and static conversion model is obtained by linear fitting of dynamic mechanical parameters and static mechanical parameters. The dynamic and static conversion model is constructed under the condition of no damage to the rock core, and the rock core utilization rate is increased.

The invention discloses an acoustic black hole structure and a vibration damping device.The acoustic black hole structure comprises an acoustic black hole body and a damping layer, the acoustic black hole body is provided with a uniform thickness area and an acoustic black hole area, the acoustic black hole area is provided with a plurality of grooves, the grooves are distributed from the first end to the second end of the acoustic black hole area, and the damping layer is arranged between the first end and the second end of the acoustic black hole area. The depths of the grooves are gradually increased in the direction from the first end to the second end, and the damping layer is arranged in the acoustic black hole area. By machining the groove in the acoustic black hole area, the local bending rigidity of the acoustic black hole body is changed, the bending wave speed of the acoustic black hole body is reduced, the acoustic black hole effect is achieved, due to the arrangement of the groove, the local resonance effect can be utilized, and then structural vibration suppression in the low-frequency range is achieved; the problem that a traditional acoustic black hole structure is poor in low-frequency-band vibration reduction effect is solved, in addition, thickness cutting of an acoustic black hole area of an original structure is avoided, and the manufacturing difficulty and the requirement for the precision of machining equipment are lowered.

The invention discloses a real-time rendering method and system for physical simulation water surface waves, and the method comprises the following steps: constructing a generative adversarial network, obtaining a wave vector and an environment parameter variable of the waves, inputting the environment parameter variable into the pre-constructed generative adversarial network, and calculating the height of the waves through a Tessendorf method; calculating wave displacement through Fourier transform and inverse transform in a frequency domain based on the wave vector; calculating the velocity complex amplitude of the corresponding wave based on the wave vector, introducing a micro-scale vortex velocity field based on a particle system, and calculating the wave velocity based on the velocity complex amplitude and the micro-scale vortex field; and based on the wave height, the wave displacement and the wave speed, performing water surface wave rendering by adopting multi-cascade dynamic. According to the method, the physical rationality and visual authenticity of water surface wave simulation are improved, and water body physical simulation is promoted to develop from visual driving to the fusion direction of physical driving and data driving.

The present invention relates to a method for estimating the severity of vibration, which is the product of vibration frequency f by antinode amplitude of vibration A, and for estimating fatigue lifetime or damage of a suspended electrical cable span of overhead power lines, said suspended electrical cable span having a sag possibly negligible with respect to span length, and a mean local tension H, and a local oscillating motion amplitude u(x, t) with a local space derivative of motion (I), and being subject to a variation of said tension H, motion amplitude u(x, t) and said space derivative over time (I) due to vibration, wherein said estimation of the severity of vibration Af is obtained from the measurements of said amplitude motion u(x, t) and said space derivative of the motion amplitude (I) according to the formula (II), where ω, (III), H, m, (I) and (IV), are respectively the pulsation of the oscillating motion, the wave speed, the mean local tension of the suspended cable span, the mass per unit length of the suspended cable span, the space derivative of said motion amplitude, and the acceleration of said motion amplitude; and wherein said fatigue lifetime or damage are obtained from a number of cycles estimated from said tension frequency analysis and a stress level is obtained from said motion amplitude and said space derivative of the motion amplitude.