The structure damage detection with spatial wavelets was approached. First, a plane stress problem, a rectangular plate containing a short crack under a distributed loading on the edge, was investigated. The displac...The structure damage detection with spatial wavelets was approached. First, a plane stress problem, a rectangular plate containing a short crack under a distributed loading on the edge, was investigated. The displacement response data along the parallel and perpendicular lines at different positions from the crack were analyzed with the Haar wavelet. The peak in the spatial variations of the wavelets indicates the direction of the crack. In addition, a transverse crack in a cantilever beam was also investigated in the same ways. For these problems, the different crack positions were also simulated to testify the effectiveness of the technique. All the above numerical simulations were processed by the finite element analysis code, ABACUS. The results show that the spatial wavelet is a powerful tool for damage detection, and this new technique sees wide application fields with broad prospects. (Edited author abstract) 14 Refs.展开更多
After briefly introducing the characteristics of 1/f noise in millimeter wave focalplane array detectors, the paper analyses the relation of wavelet transform and 1/f noise in detail, suggests the fashion of decorrela...After briefly introducing the characteristics of 1/f noise in millimeter wave focalplane array detectors, the paper analyses the relation of wavelet transform and 1/f noise in detail, suggests the fashion of decorrelating 1/f noise using the wavelet transform and deduces the relative expressions. The results of computer simulation show good effectiveness.展开更多
基金The project supported by the National Natural Science Foundation of China
文摘The structure damage detection with spatial wavelets was approached. First, a plane stress problem, a rectangular plate containing a short crack under a distributed loading on the edge, was investigated. The displacement response data along the parallel and perpendicular lines at different positions from the crack were analyzed with the Haar wavelet. The peak in the spatial variations of the wavelets indicates the direction of the crack. In addition, a transverse crack in a cantilever beam was also investigated in the same ways. For these problems, the different crack positions were also simulated to testify the effectiveness of the technique. All the above numerical simulations were processed by the finite element analysis code, ABACUS. The results show that the spatial wavelet is a powerful tool for damage detection, and this new technique sees wide application fields with broad prospects. (Edited author abstract) 14 Refs.
文摘After briefly introducing the characteristics of 1/f noise in millimeter wave focalplane array detectors, the paper analyses the relation of wavelet transform and 1/f noise in detail, suggests the fashion of decorrelating 1/f noise using the wavelet transform and deduces the relative expressions. The results of computer simulation show good effectiveness.