20results about "Velocity propogation" patented technology

This invention discloses a method, system, and storage medium for extracting subsurface channel parameters based on layered recovery and step-by-step uplift. The method includes: preprocessing a sound velocity profile to form a standardized sound velocity profile; searching for candidate local minima; for each candidate local minima, searching for sound velocity sampling points that satisfy the stable recovery condition from the lowest qualified recovery layer upwards and downwards; if both sides exist and the waveguide thickness is greater than a preset thickness threshold, it is determined as a candidate subsurface channel; starting from the lowest qualified recovery layer, the target recovery layer is gradually increased, and the stable recovery determination is repeated until either side no longer satisfies the determination of the highest common recovery layer and the characteristic parameters are calculated; when there are multiple candidates, the output is selected according to the representativeness rule. This invention unifies the existence determination and parameter extraction under the physical constraints of bilateral stable recovery, solving the problems of easy interference and boundary instability in the prior art, and has the advantages of accurate identification and strong anti-interference ability.

This invention relates to the field of marine environmental monitoring technology. Specifically, it relates to a high-power marine acoustic tomography system for marine environmental monitoring. The system includes a regional deployment and clock synchronization module, a signal generation and high-power transmission module, a signal reception and propagation time measurement module, a sound velocity calculation and reference area selection module, a sound velocity parameter weighted correction module, and an environmental parameter inversion and result fusion module. By constructing a standardized end-to-end technical solution from regional deployment, signal transmission and reception, parameter calculation to environmental inversion, it achieves large-area, high-precision, and continuous environmental monitoring of target marine areas. Through standardized gridded regional division, GPS carrier phase positioning node calibration, and high-precision clock synchronization using GPS-acquired atomic clocks, a standardized underwater mooring node network is established, ensuring the basic accuracy of underwater acoustic signal propagation time measurement and sound velocity parameter calculation from a hardware deployment perspective.

In the present invention, an acoustic wave is transmitted to a first surface S1 of an object S having acoustic anisotropy by a transmission unit 11a disposed on the first surface S1. A plurality of acoustic waves propagating through the inside of the object S at different angles are received by a reception unit 11b disposed on the first surface S1 of the object S or a second surface S2 opposing the first surface S1, and thereby a plurality of pieces of reception information are acquired. A plurality of propagation velocity vectors are calculated based on the plurality of pieces of reception information. A propagation wavefront shape model corresponding to the acoustic anisotropy of the object S is determined based on the plurality of propagation velocity vectors. A horizontal propagation velocity parallel to the first surface S1 is calculated based on the propagation wavefront shape model.

The application discloses a method for compensating sound velocity in underwater acoustic positioning based on vertical total time delay random walk, and belongs to the field of underwater acoustic navigation and positioning. The method comprises the following steps: collecting two-way time delay observation data in underwater acoustic positioning; establishing a marine sound velocity compensation formula; defining a vertical total time delay, and establishing a conversion function between marine sound velocity variation and the vertical total time delay; calculating a rough prior value of the vertical total time delay based on the conversion function, and calculating random walk process noise of the vertical total time delay by using a first-order Markov process; using the two-way time delay observation data, the rough prior value and the random walk process noise, and using extended Kalman filtering to accurately estimate the vertical total time delay, and then substituting the vertical total time delay into the conversion function to obtain marine sound velocity variation, so that the sound velocity compensation is realized. The application does not need to increase additional sound velocity measuring equipment, can compensate marine sound velocity variation error in real time and online, improves underwater acoustic positioning efficiency, and improves time resolution of marine sound velocity variation detection.

This application relates to a laser ultrasonic rock velocity measurement device, comprising: a motor installed inside a gantry-type mechanical stage; a gantry frame mounted on the surface of the gantry-type mechanical stage; a pulsed laser and a laser vibrometer coupled along the Y-axis of the outer surface of the gantry frame; and a prism and a convex lens coupled along the Z-axis of the outer surface of the gantry frame. A preset control system controls the motor to move the pulsed laser and laser vibrometer along the Y-axis of the gantry frame, as well as the prism and convex lens along the Z-axis, causing the laser emitted by the pulsed laser and laser vibrometer to pass through the prism and convex lens to two preset laser points on a preset rock sample. The acoustic velocity between the two preset laser points is calculated based on a preset length between the two preset laser points and the acquired first arrival time. This improves the accuracy of acoustic velocity measurement on rock surfaces.

The application discloses a shearing device, which comprises a casing, a baffle, a probe and a first driving assembly. The casing is arranged in a pre-drilled hole to form a detection channel, and at least one opening is arranged along the axial length direction of the casing. The probe is arranged in the casing, and the opening is used to ensure that the shear wave generated by a seismic source can pass through the casing and be received by the probe, thereby avoiding the influence or even shielding of the casing on the wave velocity propagation. The baffle is slidably arranged at the opening of the casing along the axial direction of the casing. The first driving assembly can drive the probe and the baffle to move up and down in the casing along the axial direction, so that segmented shear wave velocity tests at different depths can be realized. The positional relationship between the probe and the baffle is limited as follows: (the horizontal distance between the probe and the bottom side of the baffle, the vertical distance between the probe and the bottom side of the baffle, and the repose angle of the accumulated slope body), so that the baffle can block part of the falling material during the upward movement of the probe, the probe is ensured to be located in an area that is not covered by the falling cone, and the probe is prevented from being buried.

This invention discloses a single-shot shock wave velocity measurement system and method with timing calibration capability. The single-shot shock wave velocity measurement system includes a target chamber, a probe laser generation module, a timing calibration target, an interferometer, a streak camera, a focusing lens, a timing laser introduction module, and multiple main laser generation modules. During the timing calibration of the single-shot shock wave velocity measurement system, a customized timing calibration target reflects the main laser signal and the probe laser signal along the same optical path. A focusing lens is used to improve the signal-to-noise ratio. Simultaneously, a dedicated timing laser transmission component introduces the timing laser signal into the slit of the streak camera. This allows for the simultaneous acquisition of the main laser signal, the probe laser signal, and the timing laser signal in a single-shot measurement, achieving in-situ precise timing calibration for a velocity measuring instrument corresponding to any reflective surface.

The application discloses a method for measuring the sound velocity and elastic modulus of an organic semiconductor thin film material, and relates to the field of ultrafast optical technology; the method comprises the following steps: building an optical system; taking a femtosecond pulse light as pump light, periodically modulating the absorbance of the measured organic semiconductor thin film material by using the pump light, obtaining the probe light intensity under the action of the pump light and the action of no pump light, and obtaining the transient absorption kinetics spectrum of the measured organic semiconductor thin film material; analyzing the periodic change of the ground state bleaching signal in the transient absorption kinetics spectrum, measuring the frequency of coherent oscillation; measuring the sound velocity based on the relationship between the frequency and the sound velocity and the thickness of the organic semiconductor thin film material; and measuring the elastic modulus based on the relationship between the sound velocity and the elastic modulus and the material density of the organic semiconductor thin film material. In the application, the measuring method adopts a completely non-contact optical detection mode, the sound velocity and the elastic modulus of the thin film material are obtained by detecting the frequency of the coherent oscillation formed in the thin film.

The application relates to a cooking recognition method based on a material of a pot and an intelligent electric appliance, and is applied to the field of intelligent electric appliances. A piezoelectric sensor is arranged in the intelligent electric appliance in linkage with the pot. The method comprises the following steps: when the pot is in a cooking state, a collision sound wave signal of the pot collected by the piezoelectric sensor is received; the collision sound wave signal is generated by the collision between the pot and a cooking tool during cooking of a user; based on the collision sound wave signal, a current attenuation time constant corresponding to the pot is determined; the current attenuation time constant is used for representing the speed at which the collision sound wave signal disappears after the current pot collides; according to an initial attenuation time constant of the pot, the current attenuation time constant is compensated to obtain a compensated attenuation time constant; the initial attenuation time constant is related to sound wave characteristics corresponding to pots of different material types; and based on the compensated attenuation time constant, a cooking mode of the pot is recognized. Through the application, the accuracy of cooking mode recognition is improved.

The microphone array, the sound velocity estimation method, the sound pickup method and the related device and equipment provided by the embodiment of the application are applied to the technical field of voice, the microphone array comprises: N sound vector microphones, which are used to pick up sound signals of a target sound source; wherein the distance between at least two sound vector microphones in the N sound vector microphones is within a distance range of 0.02 meters to 5 meters, and N is an integer greater than 1. The accuracy and real-time performance of sound velocity estimation are improved.

The application relates to underwater acoustic positioning and relates to a method for rapidly estimating the depth of a low-frequency remote sound source in the Arctic ocean, which matches the upper limit of the normal mode frequency. The sound speed profile in the deep sea of the Arctic results in the vertical coverage range of the normal mode eigenfunction decreasing with the increase of the frequency. When the sound source depth is greater than the vertical coverage range of the eigenfunction, the normal mode cannot be excited, which leads to the normal mode having an upper limit of the frequency under the condition of the sound speed profile in the deep sea of the Arctic. The upper limit of the frequency is directly related to the sound source depth. Therefore, the sound source depth can be estimated by matching the upper limit of the frequency of each normal mode in the received sound signal and the upper limit of the frequency obtained through model simulation. The measured upper limit of the frequency is estimated according to a time-frequency analysis diagram. The relationship between the upper limit of the frequency of the normal mode and the sound source depth is calculated according to the measured environment by using a model. The sound source depth estimation can be obtained by comparison and matching. The above method for rapidly estimating the depth of a low-frequency remote sound source in the Arctic ocean can be realized by using a single hydrophone.

The invention relates to the technical field of acoustic engineering, in particular to an equivalent substitution method and system for sound propagation analysis of a volume sound source in a complex sound field environment. The method comprises the following steps: establishing a finite element model of a volume sound source containing complex boundary conditions by utilizing engineering software, carrying out truncation processing on a computational domain, and calculating and obtaining sound pressure and normal vibration velocity on a closed integral surface surrounding the volume sound source; based on the sound pressure and the normal vibration velocity, performing external sound field solution on the closed integral surface by adopting a free field sound radiation integral mode to obtain sound pressure distribution on at least two layers of enveloping surfaces located on the outer side of the volume sound source; arranging a plurality of equivalent point sound sources in the volume sound source, constructing an equivalent source solution equation by taking the sound pressure on at least two layers of envelope surfaces as a matching target, and calculating the source intensity of each equivalent point sound source; and based on the positions of the equivalent point sound sources and the corresponding source intensities of the equivalent point sound sources, accumulative calculation of the volume sound sources in a complex sound field environment is realized by adopting a channel propagation method based on the point sound sources, so that propagation analysis is carried out.

A pressure sensor for measuring high pressures includes: a housing having a sealed volume filled with a compressible fill liquid, wherein the housing includes an elastically deflectable diaphragm having a rear side facing the filled volume and a front side opposite the rear side such that the diaphragm transmits a pressure applied to the front side of the diaphragm to the fill liquid; and a measuring unit adapted to ascertain a variable dependent on velocity of sound in the fill liquid and, based on the measured variable, to determine a pressure measured value representing the pressure on the front side of the diaphragm, wherein the fill liquid contains an organic compound, which is present in the fill liquid at a volume fraction of greater than 99%.

The application provides an underwater low-frequency noise comprehensive test system, which comprises an underwater vehicle platform, an environment sensing calibration module, a fixed underwater measurement array, an adaptive signal processing module, a three-dimensional positioning module and a target feature extraction and analysis module; the underwater vehicle platform is used for maneuvering deployment and recovery of the fixed underwater measurement array; the environment sensing calibration module is used for obtaining underwater environment characteristic benchmarks; the fixed underwater measurement array is used for receiving underwater target radiation noise; the adaptive signal processing module is used for extracting target noise signals; the three-dimensional positioning module is used for three-dimensional positioning of the vehicle, the measurement array and the underwater target; and the target feature extraction and analysis module is used for processing the target noise signals to extract noise features; through cooperative work of the underwater vehicle and the fixed measurement array, the scheme realizes high-precision, comparability and multi-dimensional comprehensive test of underwater low-frequency noise in a complex environment.

The application discloses a reservoir siltation dynamic development acoustic monitoring and identification integrated system and an operation method, relates to the technical field of underwater siltation monitoring and identification, and comprises the following steps: early preparation for system operation; after multi-source synchronous collection and classified storage of field data, forming a standardized data set; after fine processing of the standardized data set, constructing an underwater three-dimensional terrain model; according to a preset cycle, cyclically executing and constructing a time sequence terrain model library based on the underwater three-dimensional terrain model of each cycle; through the time sequence terrain model library, calculating time sequence terrain difference value data and obtaining siltation data of different cycles; based on the time sequence terrain difference value data and the siltation data of different cycles, respectively performing siltation feature identification and siltation dynamic development prediction, and outputting a standardized monitoring report; through construction of a full-link collaborative monitoring system, full-process monitoring of siltation dynamic development, high-precision modeling and intelligent identification are realized, and the purpose of providing reliable data support for reservoir desilting operation and operation scheduling is achieved.

The utility model relates to the technical field of acoustic logging instruments, in particular to a novel delay body structure suitable for an acoustic velocity measuring probe for solid mineral exploration, which comprises a first delay body, a connecting sleeve is sleeved at one end of the first delay body, and a second delay body is arranged in the other end of the connecting sleeve. The second sound delaying body and the first sound delaying body are both fixedly connected with abutting rings, the second sound delaying body and the first sound delaying body are both sleeved with fixing bases, one fixing base is fixedly connected with a receiving crystal, the other fixing base is fixedly connected with an emitting crystal, and the two fixing bases are fixed through a fixing mechanism. According to the sound delay structure, the sound wave duration delay effect in the logging instrument is improved, the mechanical strength of the sound delay structure is enhanced, data measured by the instrument is more accurate, and the anti-seismic performance is more reliable.

The application relates to the technical field of underwater acoustic engineering, in particular to a deep-sea direct sound area boundary distinguishing method based on sound field propagation characteristics and an adaptive difference algorithm, which breaks through the bottleneck of the prior art by designing an adaptive processing strategy and a high-precision difference algorithm, realizes accurate determination of the direct sound area boundary, and has obvious scientific significance for deep-sea direct sound area boundary judgment.

The application provides a buoy cooperative underwater positioning system based on multipath suppression and sound velocity profile correction, and has the characteristics that the system comprises an intelligent buoy network module, a sound velocity measurement module, a signal suppression module and a cooperative positioning module; the intelligent buoy network module is used for constructing a positioning reference network through a plurality of buoys distributed in space in a target water area; the sound velocity measurement module is used for obtaining sound velocity distribution information of an underwater environment; the signal suppression module is used for identifying and suppressing multipath propagation interference in an underwater acoustic channel; and the positioning solution module is used for obtaining an accurate three-dimensional space position of an underwater target; through the cooperative positioning mechanism of multipath inversion suppression and trajectory prediction constraint, the underwater target positioning system achieves the technical effects of high positioning accuracy, strong stability and good robustness in a complex underwater acoustic environment.

This invention relates to a method for measuring the sound velocity of materials based on an envelope cross-correlation algorithm, belonging to the field of automated detection technology. It addresses the problem of severe waveform distortion interference in existing sound velocity measurements of internally inhomogeneous materials. The method includes the following steps: initialization settings and benchmark acquisition; point-by-point scanning of the current scanning surface of the sample to obtain sample echoes; plotting the sound velocity distribution map of the current scanning surface of the sample; rotating the sample to continue measurement until the detection of three orthogonal surfaces is completed; and obtaining the average sound velocity of the sample. Applying this material sound velocity measurement method can eliminate interference from scattering attenuation and dispersion effects caused by material anisotropy, reduce "period jump" errors caused by carrier phase ambiguity, effectively improve the signal-to-noise ratio of the detection signal, achieve automation and high repeatability of sound velocity measurement, and improve the accuracy of identifying minute sound velocity differences.