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Generalized two-dimensional correlation near-infrared spectroscopy and principal component analysis of the structures of methanol and ethanol 被引量:5
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作者 Liu Hao Xu JianPing +1 位作者 Qu LingBo Xiang BingRen 《Science China Chemistry》 SCIE EI CAS 2010年第5期1154-1159,共6页
Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal c... Liquid state methanol and ethanol under different temperatures have been investigated by FT-NIR(Fourier transform nearinfrared) spectroscopy,generalized two-dimensional(2D) correlation spectroscopy,and PCA(principal component analysis) . First,the FT-NIR spectra were measured over a temperature range of 30-64(or 30-71) °C,and then the 2D correlation spectra were computed.Combining near-infrared spectroscopy,generalized 2D correlation spectroscopy,and references,we analyzed the molecular structures(especially the hydrogen bond) of methanol and ethanol,and performed the NIR band assignments. The PCA method was employed to verify the results of the 2D analysis.This study will be helpful to the understanding of these reagents. 展开更多
关键词 NIR(near-infrared) two-dimensional (2D) CORRELATION spectroscopy principal component analysis (PCA) METHANOL ETHANOL
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基于分块的2DPCA人脸识别方法
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作者 李靖平 《浙江万里学院学报》 2014年第2期93-98,97,共6页
文章将分块理论与2DPCA方法相结合,研究分块二维主成分分析法(M-2DPCA)在人脸识别中的应用。对人脸图像矩阵进行分块,用形成的子图像矩阵直接构造总体散布矩阵并求解对应的特征向量,利用提取的特征向量对图像进行特征的提取与分析... 文章将分块理论与2DPCA方法相结合,研究分块二维主成分分析法(M-2DPCA)在人脸识别中的应用。对人脸图像矩阵进行分块,用形成的子图像矩阵直接构造总体散布矩阵并求解对应的特征向量,利用提取的特征向量对图像进行特征的提取与分析,进行人脸识别。基于Yale人脸数据库的实验显示,在相同训练样本和特征向量条件下,M-2DPCA比2DPCA算法具有更高的识别率。结论 M-2DPCA充分利用了图像的协方差信息,在人脸识别方面具有较高的识别率和鲁棒性方面,对进一步研究人脸识别具有重要的意义。 展开更多
关键词 二维主成分分析 分块二维主成分分析法 特征提取 人脸识别 two-dimensional principal component analysis (2DPCA)
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Damage detection of 3D structures using nearest neighbor search method 被引量:1
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作者 Ali Abasi Vahid Harsij Ahmad Soraghi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期705-725,共21页
An innovative damage identification method using the nearest neighbor search method to assess 3D structures is presented.The frequency response function was employed as the input parameters to detect the severity and ... An innovative damage identification method using the nearest neighbor search method to assess 3D structures is presented.The frequency response function was employed as the input parameters to detect the severity and place of damage in 3D spaces since it includes the most dynamic characteristics of the structures.Two-dimensional principal component analysis was utilized to reduce the size of the frequency response function data.The nearest neighbor search method was employed to detect the severity and location of damage in different damage scenarios.The accuracy of the approach was verified using measured data from an experimental test;moreover,two asymmetric 3D numerical examples were considered as the numerical study.The superiority of the method was demonstrated through comparison with the results of damage identification by using artificial neural network.Different levels of white Gaussian noise were used for polluting the frequency response function data to investigate the robustness of the methods against noise-polluted data.The results indicate that both methods can efficiently detect the damage properties including its severity and location with high accuracy in the absence of noise,but the nearest neighbor search method is more robust against noisy data than the artificial neural network. 展开更多
关键词 damage identification damage index frequency response function two-dimensional principal component analysis nearest neighbor search artificial neural network white Gaussian noise
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RF-PSSM:A Combination of Rotation Forest Algorithm and Position-Specific Scoring Matrix for Improved Prediction of Protein-Protein Interactions Between Hepatitis C Virus and Human
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作者 Xin Liu Yaping Lu +3 位作者 Liang Wang Wei Geng Xinyi Shi Xiao Zhang 《Big Data Mining and Analytics》 EI CSCD 2023年第1期21-31,共11页
The identification of hepatitis C virus(HCV)virus-human protein interactions will not only help us understand the molecular mechanisms of related diseases but also be conductive to discovering new drug targets.An incr... The identification of hepatitis C virus(HCV)virus-human protein interactions will not only help us understand the molecular mechanisms of related diseases but also be conductive to discovering new drug targets.An increasing number of clinically and experimentally validated interactions between HCV and human proteins have been documented in public databases,facilitating studies based on computational methods.In this study,we proposed a new computational approach,rotation forest position-specific scoring matrix(RF-PSSM),to predict the interactions among HCV and human proteins.In particular,PSSM was used to characterize each protein,two-dimensional principal component analysis(2DPCA)was then adopted for feature extraction of PSSM.Finally,rotation forest(RF)was used to implement classification.The results of various ablation experiments show that on independent datasets,the accuracy and area under curve(AUC)value of RF-PSSM can reach 93.74% and 94.29%,respectively,outperforming almost all cutting-edge research.In addition,we used RF-PSSM to predict 9 human proteins that may interact with HCV protein E1,which can provide theoretical guidance for future experimental studies. 展开更多
关键词 protein-protein interactions hepatitis C virus position specific scoring matrix two-dimensional principal component analysis rotation forest
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Micro-Expression Recognition Algorithm Based on Information Entropy Feature
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作者 吴进 闵育 +1 位作者 杨小蝶 马思敏 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第5期589-599,共11页
The intensity of the micro-expression is weak,although the directional low frequency components in the image are preserved by many algorithms,the extracted micro-expression ft^ature information is not sufficient to ac... The intensity of the micro-expression is weak,although the directional low frequency components in the image are preserved by many algorithms,the extracted micro-expression ft^ature information is not sufficient to accurately represent its sequences.In order to improve the accuracy of micro-expression recognition,first,each frame image is extracted from,its sequences,and the image frame is pre-processed by using gray normalization,size normalization,and two-dimensional principal component analysis(2DPCA);then,the optical flow method is used to extract the motion characteristics of the reduced-dimensional image,the information entropy value of the optical flow characteristic image is calculated by the information entropy principle,and the information entropy value is analyzed to obtain the eigenvalue.Therefore,more micro-expression feature information is extracted,including more important information,which can further improve the accuracy of micro-expression classification and recognition;finally,the feature images are classified by using the support vector machine(SVM).The experimental results show that the micro-expression feature image obtained by the information entropy statistics can effectively improve the accuracy of micro-expression recognition. 展开更多
关键词 micro-expression recognition two-dimensional principal component analysis(2DPCA) optical flow information entropy statistics support vector machine(SVM)
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