24 results about "Echo time" patented technology

This invention discloses a phased array ultrasonic defect intelligent identification and data analysis system, relating to the field of PAUT (Polymerization and Angiography). It includes: an acquisition module for driving a phased array ultrasonic sensor array to perform weld seam scanning according to preset scanning rules, simultaneously acquiring and outputting ultrasonic echo time-series data across the entire depth range of the weld seam; and a preprocessing module for receiving the ultrasonic echo time-series data, performing data correction, noise filtering, and initial screening of effective signals, while simultaneously receiving feature anchoring parameters output by a mapping module, refining the signals in the corresponding regions, and outputting the results. This invention enables continuous, blind-zone-free scanning across the entire thickness and width range of the weld seam, simultaneously completing accurate echo signal correction and defect feature extraction, improving defect identification accuracy through closed-loop adaptive processing, accurately determining defect types and calculating their spatial location, size, and other core parameters, and simultaneously completing defect data statistical analysis and welding process correlation.

This invention discloses a multi-node collaborative electromagnetic ultrasonic online monitoring method and system. The invention relates to the technical field of online monitoring, introducing orthogonal code demodulation into multiple electromagnetic ultrasonic probes to ensure complementary interference between the probes and the same object under test. It collects detection data output from each monitoring node and extracts the echo timestamp of the object under test. Clock drift of each monitoring node is compensated in reverse along this echo timestamp to trigger spatiotemporal alignment of the detection data. An attention mechanism is then used to construct a corresponding multi-node collaborative detection system, improving its accuracy. Based on the dynamic identification of multiple electromagnetic ultrasonic online monitoring contents, corresponding suspected defect data is determined. This suspected defect data is loaded into the online monitoring finite element module, and the corresponding online monitoring defect path is determined by combining the corresponding multi-physics coupling relationship, improving the accuracy of the online monitoring defect path.

A method according to the invention for acquiring T2*-weighted measurement data of a test object using a magnetic resonance system comprises the steps: - irradiating a first RF excitation pulse to excite spins in a first layer in the test object, - switching gradients to generate at least one gradient echo signal, - after an echo time following the irradiation of the first RF excitation pulse, acquiring a first gradient echo signal from the first layer, - after the irradiation of the first RF excitation pulse and before the elapsed echo time following the first RF excitation pulse, irradiating at least one further RF excitation pulse to excite spins in a further layer,wherein, before the application of a further RF excitation pulse and after each RF excitation pulse preceding the further RF excitation pulse, a pre-rephasing gradient of a moment corresponding to the further RF excitation pulse following the pre-rephasing gradient is switched, - recording generated further gradient echo signals from further layers. By switching the pre-rephasing gradients according to the invention, gradient echo signals of the spins of different layers excited by the first RF excitation pulse and the at least one further RF excitation pulse can be separated. Thus, the echo time TE, which elapses until a first gradient echo signal is measured after the first RF excitation pulse, can be used to generate and measure further gradient echo signals in further layers after the first gradient echo signal, which increases the readout efficiency.

This invention discloses a method for joint parameter estimation of rotating targets based on vortex electromagnetic waves, comprising: establishing a typical detection scenario and obtaining mathematical models of the target's range, azimuth, and elevation angles in the radar coordinate system; establishing an electromagnetic vortex echo signal model and defining the parameter vector to be estimated; performing maximum likelihood estimation on the parameter vector to be estimated based on the echo time-domain signal to obtain the maximum likelihood estimator; performing time-frequency analysis on the echo signal under the multi-scattering point model, extracting the skeleton from the time-frequency spectrum to obtain the rotating Doppler curve; estimating unknown parameters from the rotating Doppler curve; and performing error analysis on the parameter vector to be estimated to derive its joint Cramer-Rao bound. Compared with traditional methods for detecting local peak points, the joint parameter estimation method for rotating targets based on vortex electromagnetic waves provided by this invention has higher accuracy and can accurately estimate the position of the rotating target.

The application particularly relates to a UAV target main body and micro-motion component echo signal separation method based on factor decomposition group sparse regularization, which comprises the following steps: firstly, constructing a radar echo time-frequency representation into a Hankel matrix; secondly, using the characteristic that the echo Hankel matrix of the target main body uniform motion has low rank, establishing a signal separation model containing a low rank term, a sparse term and a noise term; thirdly, using a factor decomposition group sparse regularization method to effectively relax the rank function in the model, so as to improve the robustness of the algorithm; finally, using a linearized alternating direction multiplier method to iteratively solve the optimization model, so as to realize effective separation of the target main body echo and the micro-motion component echo in the time-frequency domain. The application is particularly suitable for narrow-band radar and short coherent accumulation time detection conditions, can effectively overcome the problems of model mismatch and low calculation efficiency existing in traditional methods, and simulation and measured data verify that the method has good separation precision and robustness in a noise environment.

This invention provides a method, apparatus, and device for suppressing SAR composite interference. The method includes: acquiring SAR echo data containing interference; performing short-time Fourier transform processing on the interfering SAR echo data to obtain echo time-frequency map data; inputting the echo time-frequency map data into a pre-trained anti-interference model for interference suppression processing to obtain interference-suppressed echo data; processing the interference-suppressed echo data using inverse short-time Fourier transform to obtain a de-interference reconstructed signal; and performing imaging processing on the de-interference reconstructed signal to obtain an interference-suppressed SAR imaging result. The pre-trained anti-interference model is a U-shaped network framework based on a combination of a Swing Transformer module and a multi-scale feature guidance module; the pre-trained anti-interference model is trained using a composite loss function. This significantly reduces target signal loss and enhances the model's robustness in complex coupled interference scenarios.

The application discloses an intervention ultrasound surgery simulation and skill evaluation simulation method and system, relates to the technical field of ultrasound imaging simulation, and comprises the following steps: a time-anchored echo fingerprint band is established around an ultrasound probe angle change, a phase transition list is generated according to echo time sequence change, and the phase transition list is solidified to the end of a time axis to form a subsequent extraction basis; synchronous collapse trigger segments are identified relying on the phase transition list in the time-anchored echo fingerprint band, a disappearance window marking frame is generated and embedded at the end of the time-anchored echo fingerprint band to realize accurate locking of an abnormal section. Through dynamic association of the time-anchored echo fingerprint band and the phase transition list, the application maintains time continuity and phase stability of multi-layer echo signals, avoids image tomography and target area disappearance; and through coupling regulation of inverse phase traction cords, misaligned sampling grids and rhythm traction instructions, energy release and image smooth backfilling are realized, so that the continuity and stability of the image under dynamic operation are ensured.

This invention discloses a detection system and method for cable fault location, relating to the field of cable fault location technology. It acquires nanosecond-level pulse propagation front-end change trajectory data and echo peak width change data to establish a high-frequency attenuation continuous-time distribution map; extracts pulse broadening growth segments and performs front-end compression control to form a compressed pulse front-end shape; rearranges the peak time position to separate low-amplitude reflection signals; tracks its amplitude trajectory and identifies local insulation anomaly segments by comparing with the peak width evolution trajectory; establishes a distance-back mapping and corrects the echo time coordinates to obtain the fault location interval. This invention improves the ability to identify early insulation defects by constructing a continuous-time distribution map and compressing pulse broadening segments, shortening the peak diffusion time, and separating low-amplitude reflection signals within the peak; simultaneously, it improves fault location accuracy and stability by establishing a distance-back mapping relationship and dynamically correcting the echo time coordinates.

This application provides a three-dimensional morphological defect detection system based on time-of-flight and phase correction, relating to the field of forging defect detection technology. The system includes: an acquisition module for obtaining visible light images and time-of-flight depth data; a calibration and registration module for establishing a unified detection coordinate system and generating aligned images and aligned morphological data; a decisionable region generation module for determining depth anomaly regions based on echo time distribution and phase information, and forming a decisionable region mask; an index calculation module for calculating position and size indicators within the mask based on the aligned detection data; and a decision module for outputting defect detection results. This scheme improves robustness and cross-station comparability under strong reflective light and thermal disturbance conditions by eliminating unstable measurement regions and quantizing them in a unified coordinate system, making it suitable for online quality inspection and process control in forging production lines.

The application discloses a wind power pile foundation underwater broadband acoustic tomography imaging detection method and relates to the technical field of structure detection, and comprises the following steps: in the rising and falling tide alternation stage, a continuous echo time sequence is acquired through broadband acoustic tomography imaging detection, a time of arrival variation curve corresponding to the period is constructed, and a sound velocity variation mark representing the sound velocity variation trend with the tide is extracted from the time of arrival variation curve; the continuous echo time sequence is sequentially rearranged in the time of arrival around the sound velocity variation mark, a propagation path offset track corresponding to the sound velocity variation mark is formed, and a path offset scale is extracted according to the propagation path offset track. The application extracts the sound velocity variation mark and constructs the propagation path offset track, identifies the path mismatch entrance and the imaging adjustment starting point in sections, realizes the front control of the propagation deflection influence, disperses the time offset caused by the tide variation through the imaging time mapping rhythm rearrangement and the period expansion and contraction adjustment, and improves the imaging stability and the abnormal interpretation reliability.

The application discloses an optimization method, device, equipment and medium for magnetic resonance imaging, and relates to the field of magnetic resonance imaging. The method comprises the following steps: acquiring a reference longitudinal relaxation time of an imaging magnetic resonance device with a preset main magnetic field strength; constructing a linkage fitting function between TR and TI parameters based on the reference longitudinal relaxation time, taking the maximum difference value between an image signal of a hemorrhagic focus and an image signal of healthy brain parenchyma as a target; determining a target TI according to a target TR and the linkage fitting function; optimizing scanning parameters of the magnetic resonance device by using a minimum effective echo time, the target TR and the target TI; acquiring an initial magnetic resonance image, which is obtained by scanning a stroke patient by using the magnetic resonance device with the optimized parameters; and enhancing the initial magnetic resonance image by using a nonlinear stretching function to obtain a stroke triage enhanced inversion recovery image. The application can improve the image contrast of the magnetic resonance imaging.

The application provides an electromagnetic ultrasonic bolt stress detection system based on a space-time complementary algorithm, which comprises the following steps: collecting a multi-channel ultrasonic signal of a bolt to be measured to obtain a multi-channel echo signal group; performing time-varying attenuation compensation and adaptive entropy weight denoising on the multi-channel echo signal group to obtain a denoised echo signal group; extracting echo time domain features from the denoised echo signal group, performing segmented time-frequency feature extraction on the denoised echo signal group based on a short-time sliding window to obtain echo time-frequency features, and fusing the echo time domain features and the echo time-frequency features into ultrasonic time-frequency features; performing wave field reconstruction on the denoised echo signal group to obtain a spatial ultrasonic energy map, and extracting ultrasonic spatial features of the spatial ultrasonic energy map based on a self-attention map convolution network; performing correlation detection and space-time complementary modeling on the ultrasonic time-frequency features and the ultrasonic spatial features to obtain ultrasonic space-time joint features, and performing stress analysis on the ultrasonic space-time joint features to obtain bolt stress data.

The present application relates to the technical field of pole piece coating quality control, and discloses a pole piece coating quality detection method and system based on reflection and transmission ultrasonic fusion, comprising: collecting the reflection and transmission ultrasonic signals of the pole piece and completing spatial alignment, extracting the first reflection wave amplitude, interface echo time difference and other characteristics from the reflection signal, extracting the energy, center frequency offset, propagation time and other parameters from the transmission signal, constructing a joint correlation model based on the propagation characteristics of ultrasonic waves in multi-layer media, and synchronously solving the coating thickness and area density; a high-dimensional defect sensitive vector is constructed by integrating the physical consistency characteristics of the two types of signals, and precise defect determination is realized by combining spatial position and change trend verification, the system cooperates six functional units to output quality distribution map and process capability index in real time, the information limitation and interference problem of the traditional single detection mode is overcome, and the high-precision monitoring demand of the whole process of the high-speed coating production line is met.

The application discloses a kind of 3D multi-parameter simultaneous quantification of magnetic resonance imaging method including myelin water, comprising: initialization includes two T2 preparation pulse and five readout section magnetic resonance quantification sequence;Using optimization model based on Cramer-Rao lower bound and self-supervised multilayer perception, flip angle, echo time and interval time of sequence are jointly optimized;Signal dictionary is constructed using optimized parameter and the base of subspace is extracted;Original k-space data is collected to reconstruct the timing of subspace and obtain timing reconstruction image;Finally, timing signal is matched with dictionary, and T1, T2 and MWF quantitative map of whole brain are generated.The application breaks the limitation of traditional experience parameter setting, significantly improves the quantification accuracy of short T2 myelin water and conventional tissue parameters, and realizes single whole brain high-resolution multi-parameter simultaneous quantification in 3 minutes 30 seconds, greatly shortens the scanning time, and greatly improves the clinical applicability.

This invention discloses a method for detecting oblique spalling cracks in rails based on ultrasonic creeping waves, belonging to the field of data processing and display technology in rail non-destructive testing. The invention proposes: initializing a one-transmitter-one-receiver mode and sound path conversion parameters based on the first critical angle; performing relative sensitivity calibration and flaw detection sensitivity benchmark compensation calibration; acquiring echo signals on-site using a combination of sawtooth and fixed-point rotation; the instrument converts the echo time difference within the gate according to preset parameters, directly displaying the horizontal distance, depth, and sound path; and determining the damage level based on a depth threshold. This invention deeply integrates the physical mechanism of creeping wave acoustic field with data processing logic, achieving effective separation and display of shallow-depth oblique crack echoes and initial pulses, as well as accurate damage conversion and positioning. It exhibits strong resistance to surface interference and significantly improves the identification and classification capabilities of early-stage micro-cracks.

The application discloses an ultrasonic film detection method, an ultrasonic fingerprint device and electronic equipment. The method comprises the following steps: obtaining N original echo time domain data with the same sampling duration, each original echo time domain data comprising a plurality of original amplitudes, and the sampling intervals of any two adjacent original amplitudes being the same; performing fusion processing on the N original echo time domain data to determine target echo time domain data, wherein the target echo time domain data comprises a plurality of target amplitudes, and each target amplitude is determined based on N original amplitudes with the same time sequence; performing feature extraction on the target echo time domain data to determine measured features corresponding to one or more film detection indexes; and determining a film detection result based on the measured features corresponding to the one or more film detection indexes. The ultrasonic film detection method can effectively eliminate hardware jitter, increase the signal strength of the echo time domain signal, and further improve the accuracy of film detection.

The present disclosure relates to a method and device for distinguishing a high-fat voxel and generating a fat fraction map by means of magnitude-based multi-echo magnetic resonance imaging, the method including obtaining, with a magnetic resonance scanner, three or more opposed-phase OP image data corresponding to an opposed-phase and three or more in-phase IP image data corresponding to an in-phase in accordance with a plurality of echo times of a subject, confirming, with the magnetic resonance scanner, a voxel value for voxels constituting each of the image data, determining, with the magnetic resonance scanner, a high-fat voxel in which high-fat is located among the image data based on the voxel value, and generating, with the magnetic resonance scanner, a fat fraction map by selectively applying different fat fraction equations in accordance with a result of the determination of the high-fat voxel, and may be applied to other embodiments.

The present application relates to the technical field of polyester fiber ultrasonic detection, in particular to a nondestructive testing method and system based on polyester fiber material, comprising: collecting initial ultrasonic echo time domain signals of different detection points of polyester fiber material, processing through an improved ultrasonic signal reconstruction algorithm of fusion adaptive noise suppression model and waveform matching criterion, and generating characteristic enhanced ultrasonic reconstruction signals. Relying on the structure feature library of polyester fiber material, the reconstruction signals are analyzed layer by layer to generate a multi-layer structure feature mapping containing fiber orientation distribution, interface adhesion state and internal defect mask. Through the material performance degradation model integrating the mapping relationship of defect size, density and stress concentration coefficient, the defect related performance degradation parameters are calculated, the material structure integrity is evaluated in combination with the preset structure safety threshold, and the corresponding evaluation report is generated. The present application improves the signal feature recognition degree, realizes the synchronous analysis of multi-dimensional structure features, and accurately reflects the internal structure state of the material.

The application provides an electronic chart system, method and equipment with real-time forward seabed obstacle early warning function, and relates to the technical field of marine electronic information technology. The data acquisition module integrates the electronic chart reference depth, high-precision seabed topographic model, real-time dynamic data of the ship and monthly average sound velocity value based on the world ocean atlas. The forward seabed obstacle sensing and early warning module adopts a low-cost acoustic transducer with fixed emission depression angle, wide horizontal beam angle and narrow vertical beam angle, and transmits a fan-shaped acoustic beam to the lower front of the bow. The expected echo time based on the reference topography and sound velocity is calculated, and real-time comparison is made with the measured echo time. When the measured time is significantly ahead, it is determined that there is an obstacle protruding from the reference seabed in front, and its horizontal distance and height are accurately positioned according to the geometric relationship. The application realizes real-time, direct and quantitative early warning of the forward seabed obstacle of the route at low cost, and significantly improves the safety of ship navigation.

The application discloses a kind of multi-node coordination's electromagnetic ultrasonic online monitoring method and system, and the application relates to the technical field of online monitoring, to multiple electromagnetic ultrasonic probe introduction orthogonal code demodulation, so that multiple electromagnetic ultrasonic probe detects the detection of the same to-be-detected object complementary interference, the detection data output by each monitoring node is collected, and the echo timestamp of the to-be-detected object is extracted, the clock drift of each monitoring node is compensated along the echo timestamp in reverse, to trigger the space-time alignment of each detection data, and the corresponding multi-node cooperative detection system is constructed in combination with attention mechanism, improve the accuracy of multi-node cooperative detection system.According to the dynamic identification of multiple electromagnetic ultrasonic online monitoring content, the corresponding suspected defect data is determined, the suspected defect data is loaded into the online monitoring finite element module, and the corresponding online monitoring defect route is determined in combination with the corresponding multi-physical coupling relationship, to improve the accuracy of online monitoring defect route.

The application discloses a target scattering echo simulation method of an airborne vortex radar system. The implementation steps are as follows: 1. obtaining an angle information sequence of a target relative to the vortex radar system; 2. simulating a target vortex scattering coefficient time domain sequence based on an angle spectrum theory; 3. interpolating the target vortex scattering coefficient time domain sequence; and 4. simulating a vortex radar system target scattering echo time sequence. Firstly, the angle information sequence is calculated by using the motion track and the target position of the airborne vortex radar system planned in advance, and then the physical optical method is used to simulate the target vortex scattering coefficient time domain sequence based on the angle spectrum theory. On this basis, data interpolation and time domain expansion sequence construction are completed, so that the target far-field scattering receiving echo is obtained by combining the inverse Fourier transform and convolution processing. The method provides an efficient simulation approach for target echo simulation of a new system vortex radar.