Many attempts have been tried and validated for Lamb wave phased array based damage detection. Therefore, it is not easy to achieve signal focus in the Lamb wave phased array because the dispersive characteristic of Lamb waves must be taken into account. The waveform of Lamb waves changes with travel distance because of dispersion, , ]. For bulk wave based NDT, the defect imaging performance can be significantly improved by the phased array, which is easy to achieve signal focus so that the signal-to-noise ratio can be substantially improved. Despite the advantages, the disadvantage of dispersive characteristic limits the further development of Lamb wave based NDT and SHM. Lamb wave based structural health monitoring (SHM) and nondestructive testing (NDT) is an active research topic. Lamb waves have the advantage of propagating longer distances with less attenuation than bulk waves and are sensitive to both internal and surface defects of the waveguides, , ]. By comparing the imaging results of the proposed algorithm with that of the classical TFM algorithm, it is found that the proposed algorithm can significantly reduce the background noise and thus improve the imaging performance. Then the waveform correlation coefficients between any two scattering waveforms are calculated and weighted on the corresponding amplitude used in the TFM. For each imaging point, dispersion compensation for all collected signals is respectively implemented so that the scattering waveforms can be extracted. Waveform correlation coefficients will be large if the wave packets are caused by the same imaging point, or they will be small due to the change in waveform shape arising from dispersion. In the proposed algorithm, besides the signal amplitude used in the classical TFM, the waveform correlation coefficients between any two waveforms after dispersion compensation are also utilized for damage imaging. it'll only go from the gazebo thing to the first house on the left due to the death boarders.Aimed at improving the imaging performance of the classical total focusing method (TFM), which is an effective post-processing technique for Lamb wave phased array based damage imaging, a waveform correlation factor (WCF) weighted TFM imaging algorithm is proposed. Not only that, but we can't use the entire a801 map either. sad because i want my own functional copy of the map for my tribe house _ it'll only go from the gazebo thing to the first house on the left due to the death boarders. It seems APS is in charge of the disappearing parts, but it doesn't seem like we have access to that.
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