To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform （CCT） and principal component analysis （PC...To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform （CCT） and principal component analysis （PCA） is proposed.Firstly,training samples of fabric defect images are decomposed by CCT.Secondly,PCA is applied in the obtained low-frequency component and part of highfrequency components to get a lower dimensional feature space.Finally,components of testing samples obtained by CCT are projected onto the feature space where different types of fabric defects are distinguished by the minimum Euclidean distance method.A large number of experimental results show that,compared with PCA,the method combining wavdet low-frequency component with PCA （WLPCA）,the method combining contourlet transform with PCA （CPCA）,and the method combining wavelet low-frequency and highfrequency components with PCA （WPCA）,the proposed method can extract features of common fabric defect types effectively.The recognition rate is greatly improved while the dimension is reduced.展开更多
The O-2-CCT absorption spectra of bicomponent systems were measured. The influences of various organic compounds as well as the component concentration on the O-2-CCT formation ability were investigated. The results s...The O-2-CCT absorption spectra of bicomponent systems were measured. The influences of various organic compounds as well as the component concentration on the O-2-CCT formation ability were investigated. The results show that if the difference of O-2-CCT formation ability between the two components is rather large, such as the benzene/isopropyl ether system, only the O-2-CCT absorption of benzene appears, which arises from its higher O-2-CCT formation ability. If the difference of O-2-CCT formation ability is small, such as the isopropyl ether/ethanol system and the dioxane/isopropyl ether system, it is rather easy to form a dynamic equilibrium of two O-2-CCT between the two components, then only one absorption peak appears in the whole concentration range as a result of the repeated addition of the two kinds of O-2-CCT absorption. If the difference of O-2-CCT formation ability is in medium compared with the two cases above, such as the dioxane/ethanol system, there are two kinds of O-2-CCT absorption of dioxane and ethanol in the same system in the form of an equilibrium, then two absorption peaks can be detected in the middle concentration range as a result of the repeated addition of the two kinds of O-2-CCT absorption.展开更多
基金National Natural Science Foundation of China(No.60872065)the Key Laboratory of Textile Science&Technology,Ministry of Education,China(No.P1111)+1 种基金the Key Laboratory of Advanced Textile Materials and Manufacturing Technology,Ministry of Education,China(No.2010001)the Priority Academic Program Development of Jiangsu Higher Education Institution,China
文摘To extract features of fabric defects effectively and reduce dimension of feature space,a feature extraction method of fabric defects based on complex contourlet transform （CCT） and principal component analysis （PCA） is proposed.Firstly,training samples of fabric defect images are decomposed by CCT.Secondly,PCA is applied in the obtained low-frequency component and part of highfrequency components to get a lower dimensional feature space.Finally,components of testing samples obtained by CCT are projected onto the feature space where different types of fabric defects are distinguished by the minimum Euclidean distance method.A large number of experimental results show that,compared with PCA,the method combining wavdet low-frequency component with PCA （WLPCA）,the method combining contourlet transform with PCA （CPCA）,and the method combining wavelet low-frequency and highfrequency components with PCA （WPCA）,the proposed method can extract features of common fabric defect types effectively.The recognition rate is greatly improved while the dimension is reduced.
文摘The O-2-CCT absorption spectra of bicomponent systems were measured. The influences of various organic compounds as well as the component concentration on the O-2-CCT formation ability were investigated. The results show that if the difference of O-2-CCT formation ability between the two components is rather large, such as the benzene/isopropyl ether system, only the O-2-CCT absorption of benzene appears, which arises from its higher O-2-CCT formation ability. If the difference of O-2-CCT formation ability is small, such as the isopropyl ether/ethanol system and the dioxane/isopropyl ether system, it is rather easy to form a dynamic equilibrium of two O-2-CCT between the two components, then only one absorption peak appears in the whole concentration range as a result of the repeated addition of the two kinds of O-2-CCT absorption. If the difference of O-2-CCT formation ability is in medium compared with the two cases above, such as the dioxane/ethanol system, there are two kinds of O-2-CCT absorption of dioxane and ethanol in the same system in the form of an equilibrium, then two absorption peaks can be detected in the middle concentration range as a result of the repeated addition of the two kinds of O-2-CCT absorption.
