25 results about "Wave speed" patented technology

The application relates to the field of gas pressure safety monitoring, and discloses a multi-scene gas pressure safety guarantee and remote monitoring system. The system comprises a dual-mode sensing module, a topology mapping module, a wave speed cooperation module, a fluid routing module, a routing locking module and a remote monitoring module. The wave speed cooperation module utilizes the difference between the propagation speeds of radio waves and pressure waves to send a preemptive wake-up frame, drives a downstream node to start sampling and backtrack to read a hardware cache before a pressure wave arrives, and realizes complete capture of a transient waveform. The fluid routing module constructs a high-reliability control slice containing only physically connected links and a full-through monitoring slice based on radio frequency based on fluid connectivity parameters. The routing locking module generates cascaded locking instructions bound to the control slice, prevents mis-transmission of the instructions beyond a physical breakpoint by using a routing overhead mechanism, and reports a state after a circuit is opened by the monitoring slice. The application effectively solves the problems of transient leakage of low-power devices and mismatch between wireless control logic and physical topology.

This invention belongs to the fields of rock mechanics, geological engineering, and geophysical exploration technology. Specifically, it discloses a method and system for constructing a mapping relationship between acoustic wave velocity and surrounding rock stress. The method includes: performing uniaxial graded loading on a standard sandstone sample and simultaneously measuring the P-wave velocity and S-wave velocity under each stress level; then fitting a linear mapping relationship between the P-wave / S-wave velocity ratio and the axial stress of the surrounding rock; introducing joint correction coefficients and water content correction coefficients to optimize the linear mapping relationship and constructing an acoustoelastic model; and using the acoustoelastic model and field-measured wave velocity data to invert the stress state of the actual surrounding rock, thus completing the construction of the acoustic wave velocity-surround rock stress mapping relationship. This invention solves the problems of traditional wave velocity-stress relationships, which, when describing the nonlinear response of rocks at different stress stages, are not sensitive enough to subtle stress changes and lack a complete, high-precision, and interference-resistant stress inversion calculation method, making them difficult to directly apply to complex actual engineering environments.

The application discloses an overhead line insulation defect positioning method and system, and relates to the technical field of line detection.The method comprises the following steps: setting monitoring points for receiving discharge traveling wave current signals generated by insulation defect discharge; determining the distance from the insulation defect discharge point to the monitoring points according to the time difference of arrival measured by the two monitoring points when the discharge traveling wave current signals are generated in the line, and combining the propagation speed of the discharge traveling wave current signals; and obtaining the time of the monitoring points by a GPS clock synchronization module, and calculating the position of the insulation defect.The application adopts the layout of monitoring points in the line instead of the transformer substations at both ends, reduces the influence of waveform attenuation distortion on positioning accuracy, and has little influence on the attenuation of the waveform, which can be ignored almost, according to the actually monitored waveform display.Meanwhile, the influence of sag and the uncertainty of wave speed is converted into the wave speed measured on line, so that the positioning accuracy is further improved.

The application provides a microseismic monitoring system sensor network optimization method under a known wave velocity system, first, a control equation between a sensor and a microseismic / acoustic emission source is derived by utilizing a proportional relationship between a propagation distance and time, and a distance difference equation of the microseismic / acoustic emission source is established; second, an optimization function of a single source sensor network layout is constructed according to the distance difference equation and by utilizing fisher information and probability integration of the microseismic / acoustic emission source; then, a sensor network optimization function is constructed under the condition that the entire monitoring area and the probability of the occurrence of the source at different positions are considered; finally, the constructed sensor network optimization function is solved by using an improved coding framework. The method can eliminate the influence of the sensor network on the positioning accuracy and effectively identify the optimal sensor network layout.

Systems and methods for measuring material properties of a medium are described. Operations include receiving data from a receiver such as an ultrasound receiver, the data including a representation of particle motion over time in a spatial dimension, generating a time delay map from the data, wherein a first axis of the time delay map corresponds to each of a plurality of points in the spatial dimension as a measurement point and wherein a second axis of the time delay map corresponds to each of the plurality of points in the first spatial dimension as a reference point; determining a time delay surface based on a maximum value of a cross-correlation function for the time delay map, wherein the cross-correlation function is configured to determine a relationship between a plurality of measurement points and a plurality of reference points, and determining a wave velocity based on the time delay surface.

The application relates to the technical field of fault positioning, and discloses a wind farm buried cable fault positioning method based on a traveling wave positioning method, which comprises the following steps: coupling a fault traveling wave signal, collecting and generating a head-end fault waveform data set, performing high-pass filtering and differential processing on the output edge enhanced waveform, comparing the output edge enhanced waveform with a reference voltage to generate a rising edge signal, and then locking the wind farm traveling wave arrival time; sliding matching a standard reflected waveform template with the head-end fault waveform data, intercepting a fault point reflection segment, and taking the first geometric length from the cable head end to the nearest branch point as a reference to construct a first propagation path and a second propagation path of the traveling wave propagation; eliminating the traveling wave speed variable by using the time length relationship between the first propagation path and the second propagation path, matching the obtained continuous length value to the physical topological structure of the wind farm, and outputting a cable section where the fault point is located as a final positioning result; and the application can improve the efficiency of the wind farm buried cable fault positioning.

The application provides a multi-parameter fusion asphalt mixture acoustic emission sensor layout optimization method, comprising: arranging a plurality of acoustic emission sensors at equal intervals along a straight line parallel to the longitudinal direction of the surface of the asphalt mixture to be measured, performing an acoustic emission pulse test, and measuring amplitude, ringing count and wave speed; determining an effective arrangement range in which acoustic emission signals can be effectively received according to the distance at which each index attenuates by 50%, and taking the minimum value as the initial interval of the acoustic emission sensor arrangement; according to the CRLB principle, an optimization function of the acoustic emission sensor network layout is constructed; and the optimization function in step S2 is solved by using an improved genetic algorithm. The application determines the physical space constraint of the effective arrangement of the sensor through standard attenuation testing and multi-parameter fusion, constructs a regional overall positioning accuracy optimization function that fuses the exponential wave speed equation and the spatial uncertainty of the sound source, and improves the physical accuracy and reliability of the layout optimization model from a theoretical source.

The application belongs to the technical field of tunnel engineering detection, and specifically discloses a soft surrounding rock tunnel initial support cavity detection method and system, which comprises the following steps: collecting data and calibrating positions through a radar detection vehicle, analyzing local electromagnetic wave characteristics to determine cavities and mark suspicious areas, extracting time differences to calculate cavity depths in combination with electromagnetic wave speeds, determining longitudinal lengths and transverse widths according to radar images, calculating initial detection volumes in combination with a cavity shape pattern library, confirming actual parameters through secondary reexamination, finally evaluating structure risk levels according to actual positions and volumes, and generating a detection report; the radar detection vehicle is used for non-contact geological radar detection, so that physical damage of a support structure caused by traditional drilling is avoided, the integrity of the support structure is ensured, and through quantitative criteria of multiple characteristics such as reflected wave amplitude, phase and waveform, subjective artificial judgment is replaced, the objective reliability of detection results is improved, and the detection efficiency is greatly improved in the automatic and continuous scanning mode.

The application provides a multi-modal resonant signal decoupling separation and fault ranging method, comprising the following steps: building an electromagnetic transient simulation model of a to-be-observed line; constructing a mapping database of time difference and wave velocity; obtaining a multi-modal resonant frequency spectrum database under a non-fault condition; determining a fault line section and a preliminary position based on the mapping database and a time difference method; setting a simulation fault near the preliminary position, obtaining a resonant frequency spectrum database of the fault line section through frequency domain simulation; converting a fault traveling wave signal to a frequency domain to obtain a measured frequency spectrum; reconstructing and separating the measured frequency spectrum by using an orthogonal matching pursuit algorithm to obtain a fault line frequency spectrum; and determining a fault position by calculating a correlation coefficient of the fault line frequency spectrum and the resonant frequency spectrum database through weight weighting. The application eliminates a detection blind area of a short-distance cable under a long-distance overhead line background, and improves the reliability of mixed line fault ranging.

The application provides a traction power supply fault positioning method and system for an electrified railway. A fault voltage transient signal is collected. A local measurement point and an opposite measurement point where an initial fault traveling wave first arrives are identified according to the fault voltage transient signal. Joint time-frequency analysis is performed on voltage waveforms of the local measurement point and the opposite measurement point to obtain a dominant oscillation frequency sequence. An equivalent propagation time difference of the fault traveling wave arriving at the local measurement point and the opposite measurement point is identified according to a distribution characteristic of the dominant oscillation frequency sequence. A first estimated distance and a second estimated distance of a fault point are determined based on a known wave speed of a traction network line and the equivalent propagation time difference. A fault positioning mode is determined according to a sum of the first and second estimated distances and an actual total length of a line. A fault position point of the traction power supply of the electrified railway is identified based on the fault positioning mode. The technical solution provided by the application can achieve accurate positioning of the fault position point of the traction power supply of the electrified railway under the influence of complex transient waveforms.

The application discloses a kind of beam tracking method and device, it is related to wireless network technical field, method includes S1 constructs beam change prediction model;S2 trains optimization beam change prediction model;S3 obtains MCS statistical information and SSB scanning result information;S4 generates state vector;S5 predicts output beam index variation;S6 adds beam index variation to the best wave speed index of current SSB scanning result, constructs the actual sending beam of next window period;S7 utilizes sending beam to carry out data transmission;S8 judges whether to reach beam switching point, if yes then progress S3;Otherwise, progress S6;Introduce MCS link quality information, carry out depth fusion with the high-precision MCS link quality information of coarse-grained SSB spatial domain information, improve the performance of beam tracking;Periodic interval trigger is used, timely beam adjustment can be carried out between two SSB scanning periods, and base station can also continuously observe the effect of decision during interval window.

The application discloses an EVDF acquisition method for continuous light Thomson scattering, comprising the following steps: S1, reading Thomson scattering spectrum data, and searching for a signal intensity highest point in the spectrum data; S2, if the signal intensity highest point is located at an extremely narrow peak, then taking the signal intensity highest point as a center wavelength λ0 of a wavelength axis in the spectrum data; S3, converting the wavelength axis λ in the spectrum data into a wavelength difference axis Δλ=(λ-λ0), and then converting into a frequency shift axis Δf through a light wave speed formula; and S4, further converting Δf into corresponding electronic velocity v through a Doppler frequency shift formula e , so that accurate EVDF can be obtained. The velocity determination accuracy of the application can reach 0.1 m / s in theory, and can accurately distinguish room temperature plasma and even extremely low temperature plasma below the room temperature, so that the hardware requirement is low and the cost is reduced.

This invention discloses a method and system for traction network fault location based on traveling wave ranging and clock synchronization, belonging to the field of traction network fault location technology. This invention sets up clock subsystems and measurement subsystems in substations, sectioning stations, and AT stations. A first confidence level is generated based on the crystal oscillator type and historical timekeeping error rate of the clock subsystem; a second confidence level is generated based on the fault signal collected by the measurement subsystem; and a third confidence level is generated based on the signal loss duration of the clock subsystem. The fault location is predicted by combining the reception time, the first confidence level, the second confidence level, and the third confidence level. Furthermore, a minimum reflection path is fitted based on the fault location and reflection type, and the actual wave speed is fitted based on the minimum reflection time difference to predict the clock reliability. Then, the local clock is actively calibrated based on the clock reliability. This invention can effectively improve the accuracy of traction network fault location by reducing measurement errors caused by clock asynchrony.

The present application relates to the technical field of cable fault, and more particularly to a method and system for precise positioning of medium and high voltage cable fault based on broadband pulse reflection, wherein the method comprises: exciting a medium and high voltage cable with a spread spectrum signal to obtain a full reflection signal sequence; analyzing the traveling wave characteristics of the full reflection signal sequence to obtain cable joint position calibration information and a suspected fault time section; injecting a traveling wave signal into the suspected fault time section to collect a corresponding single reflection waveform sequence; analyzing the single reflection waveform sequence fault arc electromagnetic fingerprint, performing feature correlation identification with a preset fault discharge feature table, and determining the fault discharge mechanism type; evaluating the traveling wave time delay of the suspected fault time section according to the single reflection waveform traveling wave arrival time and the cable wave speed parameter, and calculating the accurate distance of the fault point; and fusing and packaging the accurate distance of the fault point and the fault discharge mechanism type to generate cable fault joint diagnosis information.

The application provides a power distribution network fault accurate positioning method based on multi-terminal traveling wave wave head calibration and wave speed inversion, and belongs to the technical field of power distribution network fault positioning. The application comprises the following steps: installing a traveling wave collection terminal at multiple nodes of a power distribution network, and synchronously sampling to obtain a fault traveling wave signal; performing optimal phase-mode transformation to extract optimal line-mode components, and determining an initial traveling wave wave head coarse positioning time; adopting an ESMD-VMD-TEO adaptive method to calibrate the optimal line-mode components with high precision, and obtaining wave head positions of each measuring point; establishing a multi-terminal traveling wave positioning equation group based on the relationship between the wave head arrival time and the wave head position of each measuring point; constructing a weighted least square objective function based on the multi-terminal traveling wave positioning equation group, and inversely calculating a fault position, a traveling wave wave speed and a fault occurrence time by means of a Levenberg-Marquardt algorithm; constructing an energy spectrum correlation degree matrix to distinguish a fault branch; and outputting an accurate fault point position, a traveling wave wave speed and a positioning error confidence interval. The application realizes a tower level accurate positioning of a complex power distribution network fault.

The application discloses a simulation generation method and device for near-shore strong nonlinear waves and a terminal, and relates to the technical field of ocean engineering, in particular to a simulation generation method for near-shore strong nonlinear waves. The method comprises the following steps: acquiring sea surface height data of a tsunami wave at a certain position; inputting the sea surface height data into a wave speed variation and water depth variation relationship model, wherein the wave speed variation and water depth variation relationship model outputs wave flow speed; and obtaining a tsunami wave based on the sea surface height data and the wave flow speed. Compared with the prior art, the application can accurately generate strong nonlinear waves in a computational fluid dynamics model, fills the gap of the model method in this aspect, lays a foundation for the research on strong nonlinear waves, such as extreme storm surges and tsunami waves, and engineering effects thereof, and thus can more accurately understand, simulate and quantify the engineering effects of extreme wave disasters.

The application discloses an improved method for traveling wave distance measurement based on power distribution network fault location analysis, and relates to the technical field of traveling wave distance measurement, solves the technical problem that fault related paths and irrelevant branches cannot be effectively distinguished, and path identification errors are prone to occur, and the application realizes accurate identification of fault related paths, improves irrelevant branch elimination rate and multi-branch line path matching degree, reduces positioning error, through the construction of a dynamic topology directed graph + GIS spatial correlation mechanism, through terminal time difference consistency verification and physical path constraint, realizes accurate identification of fault related paths, improves irrelevant branch elimination rate and multi-branch line path matching degree, reduces positioning error, and solves the problem of wave speed uncertainty, constructs a multi-dimensional weighted model, adapts different fault scenes comprehensively, improves correction accuracy, reduces positioning error in complex scenes such as mixed lines and new energy grid connection, and meets the engineering operation and maintenance requirements.

1. The name of the design product: the fixing base of the wave speed ball. 2. The use of the design product: the whole design product is used for assisting sports fitness; the part to be protected is used for installing and fixing the wave speed ball. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: the perspective view 1. 5. Other circumstances that need to be explained: the design requests partial design protection, the red part is the part to be protected, and the gray and white part is not the part to be protected.

The application discloses an improved traveling wave distance measurement method for fault location analysis of a power distribution network, and relates to the technical field of power distribution networks. The method solves the problem of positioning deviation caused by a traditional single wave speed model, and especially the problem of false fault points caused by refraction and reflection at the connection between a cable and an overhead line. The method performs waveform translation and coincidence verification, calculates the amplitude difference average under different translation amounts, automatically identifies the optimal time alignment point, and locks the associated time difference t1. This process can effectively correct the time error caused by signal distortion, non-synchronous sampling and the like, and can improve the time difference accuracy from the microsecond level to the nanosecond level, thereby laying a foundation for subsequent accurate positioning. In the locked range interval, a plurality of associated points are randomly selected, a corrected waveform is constructed based on the attenuation ratio, and repeated verification is performed. The optimal solution is selected through a characteristic mean minimization algorithm. The mechanism can effectively suppress single measurement point error, and can improve the robustness of the positioning result through statistical average effect.

The present application relates to the technical field of automatic control of hydropower stations, and discloses a method and system for intelligent collaborative control of primary frequency modulation of a hydropower station governor, which comprises constructing a full-plant hydraulic coupling matrix according to pipe network parameters; when the rate of change of power grid frequency exceeds the limit, the pipe network execution module is divided into an active disturbance group and a pressure following group according to the coupling matrix; the active disturbance group is controlled to act to generate a hydraulic transient wave, and the actual water hammer wave speed and pipe wall friction coefficient are calculated; based on the calculated parameters and a characteristic line method calculation program, nonlinear guide vane kinematic trajectory data of the pressure following group are generated; the pressure following group is controlled to perform a phase shift delay operation and output mechanical power, and the total active power is synthesized with the power of the active disturbance group; power tracking residuals are calculated and control references are adjusted. The present application reduces the superposition degree of water hammer waves caused by synchronous action of the unit, weakens power counter-regulation caused by the water hammer effect, and improves the stability of the full-plant primary frequency modulation power output.

Methods and systems for generating charts depicting synchronous and parametric roll associated with a vessel are described herein. The method performed by the system includes accessing vessel parameters associated with a vessel traveling at sea along a route and computing rolling metrics for the vessel based on the vessel parameters. The rolling metrics includes vessel heading metrics, wave speed metrics, and specific roll metrics. Method further includes generating a polar plot linked to a location of the vessel based on the rolling metrics. Method further includes determining minimum safe speeds for the vessel based on the vessel heading metrics, and wave speed metrics. Method further includes generating regions including a safe region, an unsafe region, and an unreachable region within the polar plot based on the specific roll metrics. Method further includes generating an area surrounding the vessel within the polar plot based on the minimum safe speeds.

This invention relates to a wave time-domain feature extraction method based on a high-frequency nine-dimensional correlated motion model of a wave-measuring buoy, comprising the following steps: S1: acquiring raw observation data from a three-axis gyroscope and a three-axis accelerometer of a wave-measuring buoy; S2: defining a spatial reference coordinate system and establishing a nine-dimensional correlated motion model of the wave-measuring buoy based on the raw observation data; S3: correcting the error of the nine-dimensional correlated motion model using Kalman filtering technology; S4: defining a single wave based on the corrected nine-dimensional correlated motion model and calculating the wave height and wave period of the single wave; S5: obtaining the wave's horizontal maximum velocity vector based on the defined single wave and calculating the wave direction, wave speed, and wavelength of the single wave. This invention achieves accurate measurement of single-wave characteristics without water depth dependence.

The application provides a power distribution network traveling wave accurate positioning method and system, the method comprises the following steps: an edge intelligent terminal collects a fault traveling wave signal in real time, uses successive variation modal decomposition and continuous wavelet transform to accurately obtain a wave head timestamp, and uses Hilbert transform to calculate an instantaneous frequency, synchronously perceives clock synchronization error, environment parameter error, current sensor response error and time measurement error; a regional coordination node performs initial positioning based on a frequency-variable wave speed model and a line length model considering sag and temperature, quantifies positioning uncertainty through error propagation theory, completes fault research and judgment, and obtains a fault section; and the fault sections of all regional coordination nodes are collected to a cloud intelligent platform for global optimization calculation. The application solves the technical problems of poor real-time performance of fault positioning and isolation and untrustworthy positioning results in complex scenarios.

1. The name of the design product: wave speed ball. 2. The use of the design product: as fitness equipment, for sports fitness, yoga practice, etc. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The application discloses a Love wave propagation control method in a magnetoelastic-piezoelectric semiconductor composite structure, comprising a magnetoelastic material covering layer and a piezoelectric semiconductor substrate, wherein the magnetoelastic material covering layer and the piezoelectric semiconductor substrate are both made of transversely isotropic materials and are polarized along the depth direction; the piezoelectric semiconductor substrate and the magnetoelastic material covering layer form a layered half-space structure, a Love wave propagating along the horizontal direction is excited in the structure, and the wave speed in the Love wave propagation process is regulated by adjusting the thickness and material constant of the magnetoelastic material covering layer; the application provides a Love wave propagation control method in a magnetoelastic-piezoelectric semiconductor composite structure, which can accurately and predictably regulate the wave speed of the Love wave.