In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally...In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally demonstrate dynamic noise difference algorithm and wavelet transform modulus maximum （WTMM） to de-noising Raman anti-Stokes signal. Experimental results show that the sensing distance can increase from 3 kin to 11.5 km and the temperature accuracy increases to 1.58 ℃ at the sensing distance of 10.4kin.展开更多
Face attribute classification(FAC)is a high-profile problem in biometric verification and face retrieval.Although recent research has been devoted to extracting more delicate image attribute features and exploiting th...Face attribute classification(FAC)is a high-profile problem in biometric verification and face retrieval.Although recent research has been devoted to extracting more delicate image attribute features and exploiting the inter-attribute correlations,significant challenges still remain.Wavelet scattering transform(WST)is a promising non-learned feature extractor.It has been shown to yield more discriminative representations and outperforms the learned representations in certain tasks.Applied to the image classification task,WST can enhance subtle image texture information and create local deformation stability.This paper designs a scattering-based hybrid block,to incorporate frequency-domain(WST)and image-domain features in a channel attention manner(Squeezeand-Excitation,SE),termed WS-SE block.Compared with CNN,WS-SE achieves a more efficient FAC performance and compensates for the model sensitivity of the small-scale affine transform.In addition,to further exploit the relationships among the attribute labels,we propose a learning strategy from a causal view.The cause attributes defined using the causalityrelated information can be utilized to infer the effect attributes with a high confidence level.Ablative analysis experiments demonstrate the effectiveness of our model,and our hybrid model obtains state-of-the-art results in two public datasets.展开更多
The theoretical foundation for application of wavelet analysis to pile integrity detection has been presented. The mechanism of spectral variations of reflected pulse from various defects in piles is explained by usin...The theoretical foundation for application of wavelet analysis to pile integrity detection has been presented. The mechanism of spectral variations of reflected pulse from various defects in piles is explained by using the wave scattering theory. The theoretical analyses have been verified through the tests of model piles and a lot of engineering piles. A quantitative evaluation method for estimating damage degree of piles is proposed. The characteristic indexes describing spectrum variations of reflected signals and their critical values are given. They can be used not only to evaluate the damage degree but also to identify the kinds of pile defects.展开更多
The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification acc...The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification accuracy is investigated by converting red green blue （RGB） color space to various other color spaces. The results show that the classification performance generally changes to a large degree when performing color texture classification in various color spaces, and the opponent RGB-based wavelet scattering network outperforms other color spaces-based wavelet scattering networks. Considering that color spaces can be changed into each other, therefore, when dealing with the problem of color texture classification, converting other color spaces to the opponent RGB color space is recommended before performing the wavelet scattering network.展开更多
A new method of inhomogeneous media inversion by wavelet and the idea of inversion of singularities are described. This method is more efficient than the former linear approximation method. The theory and numerical si...A new method of inhomogeneous media inversion by wavelet and the idea of inversion of singularities are described. This method is more efficient than the former linear approximation method. The theory and numerical simulation results of this method are presented.展开更多
Cs-137 radioactive source with 661.7 keV gamma- ray energy and Am-241 with 59.5 keV gamma-ray energy were used to study the body structure of materials by examining transmitted gamma-ray spectrum using a scintillation...Cs-137 radioactive source with 661.7 keV gamma- ray energy and Am-241 with 59.5 keV gamma-ray energy were used to study the body structure of materials by examining transmitted gamma-ray spectrum using a scintillation detector, NaI(Tl). Due to specific characteristic properties of the medium, the passing Compton broad scattering spectrum contains valuable information. It is possible to mark and to specify the Compton spectrum caused by atomic specifications of Al, Cu, bone, muscle, and lipid as interactive materials. Wavelet transforms and other multi-scale analysis functions have been used for compact signal and image representations in de-noising, compression and feature detection processing problems for about twenty years. Comparing the transmitted spectra through muscle, bone and a tumor-like (fat) and analyzing each spectrum by wavelet analysis, the differences of the medium were shown. This study is devoted to use of wavelet transform for feature extraction associated with gamma spectrum, which corresponds to image pixel, and their classification in comparison with the Haar and Rbio3.1 transforms.展开更多
The application of wavelets is explored to solve acoustic radiation and scattering problems. A new wavelet approach is presented for solving two-dimensional and axisymmetric acoustic problems. It is different from the...The application of wavelets is explored to solve acoustic radiation and scattering problems. A new wavelet approach is presented for solving two-dimensional and axisymmetric acoustic problems. It is different from the previous methods in which Galerkin formulation or wavelet matrix transform approach is used. The boundary quantities are expended in terms of a basis of the periodic, orthogonal wavelets on the interval. Using wavelet transform leads a highly sparse matrix system. It can avoid an additional integration in Galerkin formulation, which may be very computationally expensive. The techniques of the singular integrals in two-dimensional and axisymmetric wavelet formulation are proposed. The new method can solve the boundary value problems with Dirichlet, Neumann and mixed conditions and treat axisymmetric bodies with arbitrary boundary conditions. It can be suitable for the solution at large wave numbers. A series of numerical examples are given. The comparisons of the results from new approach with those from boundary element method and analytical solutions demonstrate that the new techique has a fast convergence and high accuracy.展开更多
基金This work is supported by the National Natural Science Foundation of China （NSFC） under Grant Nos. 61377089 and 61527819, by Shanxi Province Natural Science Foundation under Grant No. 2015011049, by Research Project by Shanxi Province Youth Science and Technology Foundation under Grant No. 201601D021069, and by Research Project Supported by Shanxi Scholarship Council of China under Grant No. 2016-036 Key Science and Technology Research Project based on Coal of Shanxi Province （MQ2014-09）, by program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi, by Program for Sanjin Scholar.
文摘In Raman distributed temperature system, the key factor for performance improvement is noise suppression, which seriously affects the sensing distance and temperature accuracy. Therefore, we propose and experimentally demonstrate dynamic noise difference algorithm and wavelet transform modulus maximum （WTMM） to de-noising Raman anti-Stokes signal. Experimental results show that the sensing distance can increase from 3 kin to 11.5 km and the temperature accuracy increases to 1.58 ℃ at the sensing distance of 10.4kin.
基金supported by the National Key Research and Development Project of China(Grant No.2018AAA0100802)Opening Foundation of National Engineering Laboratory for Intelligent Video Analysis and Application,and Experimental Center of Artificial Intelligence of Beijing Normal University.
文摘Face attribute classification(FAC)is a high-profile problem in biometric verification and face retrieval.Although recent research has been devoted to extracting more delicate image attribute features and exploiting the inter-attribute correlations,significant challenges still remain.Wavelet scattering transform(WST)is a promising non-learned feature extractor.It has been shown to yield more discriminative representations and outperforms the learned representations in certain tasks.Applied to the image classification task,WST can enhance subtle image texture information and create local deformation stability.This paper designs a scattering-based hybrid block,to incorporate frequency-domain(WST)and image-domain features in a channel attention manner(Squeezeand-Excitation,SE),termed WS-SE block.Compared with CNN,WS-SE achieves a more efficient FAC performance and compensates for the model sensitivity of the small-scale affine transform.In addition,to further exploit the relationships among the attribute labels,we propose a learning strategy from a causal view.The cause attributes defined using the causalityrelated information can be utilized to infer the effect attributes with a high confidence level.Ablative analysis experiments demonstrate the effectiveness of our model,and our hybrid model obtains state-of-the-art results in two public datasets.
文摘The theoretical foundation for application of wavelet analysis to pile integrity detection has been presented. The mechanism of spectral variations of reflected pulse from various defects in piles is explained by using the wave scattering theory. The theoretical analyses have been verified through the tests of model piles and a lot of engineering piles. A quantitative evaluation method for estimating damage degree of piles is proposed. The characteristic indexes describing spectrum variations of reflected signals and their critical values are given. They can be used not only to evaluate the damage degree but also to identify the kinds of pile defects.
基金The National Basic Research Program of China(No.2011CB707904)the National Natural Science Foundation of China(No.61201344,61271312,11301074)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK2012329)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20110092110023,20120092120036)
文摘The optimized color space is searched by using the wavelet scattering network in the KTH_TIPS_COL color image database for image texture classification. The effect of choosing the color space on the classification accuracy is investigated by converting red green blue （RGB） color space to various other color spaces. The results show that the classification performance generally changes to a large degree when performing color texture classification in various color spaces, and the opponent RGB-based wavelet scattering network outperforms other color spaces-based wavelet scattering networks. Considering that color spaces can be changed into each other, therefore, when dealing with the problem of color texture classification, converting other color spaces to the opponent RGB color space is recommended before performing the wavelet scattering network.
文摘A new method of inhomogeneous media inversion by wavelet and the idea of inversion of singularities are described. This method is more efficient than the former linear approximation method. The theory and numerical simulation results of this method are presented.
文摘Cs-137 radioactive source with 661.7 keV gamma- ray energy and Am-241 with 59.5 keV gamma-ray energy were used to study the body structure of materials by examining transmitted gamma-ray spectrum using a scintillation detector, NaI(Tl). Due to specific characteristic properties of the medium, the passing Compton broad scattering spectrum contains valuable information. It is possible to mark and to specify the Compton spectrum caused by atomic specifications of Al, Cu, bone, muscle, and lipid as interactive materials. Wavelet transforms and other multi-scale analysis functions have been used for compact signal and image representations in de-noising, compression and feature detection processing problems for about twenty years. Comparing the transmitted spectra through muscle, bone and a tumor-like (fat) and analyzing each spectrum by wavelet analysis, the differences of the medium were shown. This study is devoted to use of wavelet transform for feature extraction associated with gamma spectrum, which corresponds to image pixel, and their classification in comparison with the Haar and Rbio3.1 transforms.
文摘The application of wavelets is explored to solve acoustic radiation and scattering problems. A new wavelet approach is presented for solving two-dimensional and axisymmetric acoustic problems. It is different from the previous methods in which Galerkin formulation or wavelet matrix transform approach is used. The boundary quantities are expended in terms of a basis of the periodic, orthogonal wavelets on the interval. Using wavelet transform leads a highly sparse matrix system. It can avoid an additional integration in Galerkin formulation, which may be very computationally expensive. The techniques of the singular integrals in two-dimensional and axisymmetric wavelet formulation are proposed. The new method can solve the boundary value problems with Dirichlet, Neumann and mixed conditions and treat axisymmetric bodies with arbitrary boundary conditions. It can be suitable for the solution at large wave numbers. A series of numerical examples are given. The comparisons of the results from new approach with those from boundary element method and analytical solutions demonstrate that the new techique has a fast convergence and high accuracy.
