Experimental study on alarming of concrete micro-crack initiation based on wavelet packet analysis

Localization of Multiple Leak Sources Using Acoustic Emission Sensors Based on MUSIC Algorithm and Wavelet Packet Analysis

“…However, wavelet packet partitions both the high and low-frequency bands into smaller subspaces, which improves the resolution of the signal. For this reason, wavelet packet analysis finds more extensive applications [19,20]. In view of its advantages, wavelet packet is applied in this study to extract the characteristic frequency bands from the AE signals.…”

Coupled Digital Image Correlation and Peridynamics for Full-Field Deformation Measurement and Local Damage Prediction

“…Specifically, the digital cameras are used to track and record a series of speckle images of the specimen surface during deformation, then the image correlation matching algorithms [Lei, Hou and Gong (2012); Chu, Ranson and Sutton (1985); Caggegi, Chevalier, Pensée et al (2016)] applied to pixel points in the digital images are adopted to determine the full-field displacement. As a full-field and non-contact measurement technique, DIC has gained great popularities in applications of various materials, such as metals [Cai, Zhang, Yang et al (2016); Tung, Shih and Kuo (2010); Pan, Yu and Wu (2015)], concrete [Jiang, Jin, Zhao et al (2017); Lei, Yang, Xu et al (2017)], polymers [Grytten, Daiyan, Polanco-Loria et al (2009) ;Jerabek, Major and Lang (2010)] and biomaterials [Murienne, Chen, Quigley et al (2016)]. As it is known, most DIC methods are based on the optical flow theory, whose accuracy is depended on the smoothness of displacement.…”

“…To improve the accuracy of DIC results with non-smooth or discontinuous deformation, many scholars have proposed some advanced strategies. Such as applying the extended finite element method in DIC simulation [Réthoré, Hild and Roux (2008) ;Lall, Kulkarni, Angral et al (2010)], coupling the wavelet packet transform and DIC [Lei, Yang, Xu et al (2017)] or directly extending standard DIC method [Réthoré, Roux and Hild (2007); Poissant and Barthelat (2010)]. However, obtaining accurate deformation measurements involving discontinuities still remains challenging.…”

Pipeline Leak Aperture Recognition Based on Wavelet Packet Analysis and a Deep Belief Network with ICR

“…WPA [20][21][22] is an effective time-frequency analysis technique for nonstationary signals, multiresolution analysis of the wavelet packet transform decomposes signals into low frequency signals and high-frequency signals. Furthermore, the process continues to decompose the following layers until reaching the preset level; as a result, the wavelet packet analysis has obviously better ability to achieve accurate local analysis.…”