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Cluster of Solutes With Spherical Distortion in Elastic Stress Field of component Crack

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Chinese Science Bulletin 1994年第9期39卷 720-724页

作者：于志伟关德林许晓磊马永庆 Institute of Metal Materials Dalian Maritime University Dalian 116024 PRC

Because of being tempted by the crack stress field, hydrogen atoms entering theinterval gap of material can cluster near the crack tip, forming hydrogen *** Qiwei and Hirth have proposed a physical model of hydrogen atomsclustering around the I-type crack tip on the basis of the elastic interaction of thelinear elastic stress field of the crack and hydrogen atoms. Huang Xianya and WuShiding measured the peak rich in hydrogen in front of the I-type crack by theion probe. Yet, the theory that the solutes cluster around the component crack tiphas not been reported.

关键词： component crack solutes with spherical distortion cluster.

Partial least squares regression and principal component analysis:similarity and differences between two popular variable reduction approaches

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General Psychiatry 2022年第1期35卷 67-71页

作者： Chenyu Liu Xinlian Zhang Tanya T Nguyen Jinyuan Liu Tsungchin Wu Ellen Lee Xin M Tu Division of Biostatistics and Bioinformatics Herbert Wertheim School of Public Health and Human Longevity ScienceUC San DiegoLa JollaCaliforniaUSA Department of Psychiatry Stein Institute for Research on AgingUC San DiegoLa JollaCaliforniaUSA

SUMMARY In many statistical applications,composite variables are constructed to reduce the number of variables and improve the performances of statistical analyses of these variables,especially when some of the variables are highly *** component analysis(PCA)and factor analysis(FA)are generally used for such *** the variables are used as explanatory or independent variables in linear regression analysis,partial least squares(PLS)regression is a better *** PCA and FA,PLS creates composite variables by also taking into account the response,or dependent variable,so that they have higher correlations with the response than composites from their PCA and FA *** this report,we provide an introduction to this useful approach and illustrate it with data from a real study.

关键词： composite composites component

Description and Classification of Leather Defects Based on Principal component Analysis

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Journal of Donghua University(English Edition) 2018年第6期35卷 473-479页

作者： DING Caihong HUANG Hao YANG Yanzhu College of Mechanical Engineering Donghua University

The accurate extraction and classification of leather defects is an important guarantee for the automation and quality evaluation of leather industry. Aiming at the problem of data classification of leather defects,a hierarchical classification for defects is ***,samples are collected according to the method of minimum rectangle,and defects are extracted by image processing *** to the geometric features of representation, they are divided into dot,line and surface for rough classification. From analysing the data which extracting the defects of geometry,gray and texture,the dominating characteristics can be acquired. Each type of defect by choosing different and representative characteristics,reducing the dimension of the data,and through these characteristics of clustering to achieve convergence effectively,realize extracted accurately,and digitized the defect characteristics,eventually establish the database. The results showthat this method can achieve more than 90% accuracy and greatly improve the accuracy of classification.

关键词： defect detection hierarchical classification principal component analysis reduce dimension clustering model

The Formation Mechanism of Hydrogeochemical Features in a Karst System During Storm Events as Revealed by Principal component Analysis

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地学前缘 2009年第S1期16卷 33-34页

作者： Pingheng Yang Daoxian Yuan Kuang Yinglun,Wenhao Yuan,Peng Jia,Qiufang He 1.School of Geographical Sciences,Southwest University,Chongqing 400715,China. 2.Laboratory of Geochemistry and Isotope,Southwest University,Chongqing 400715,China 3.The Karst Dynamics Laboratory,Ministry of Land and Resources,Institute of Karst Geology,Chinese Academy of Geological Sciences,Guilin 541004,China

The hydrogeochemical parameters of Jiangjia Spring,the outlet of Qingrnuguan underground river system(QURS) in Chongqing,were found responding rapidly to storm events in late April,2008.A total of 20 kinds of hydrogeo... 详细信息

关键词： rainfall principal component analysis(PCA) soil erosion agricultural activities karst hydrogeochemical feature Qingmuguan

SA BASED SOFTWARE DEPLOYMENT RELIABILITY ESTIMATION CONSIDERING component DEPENDENCE

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Journal of Electronics(China) 2011年第1期28卷 118-125页

作者： Su Xihong Liu Hongwei Wu Zhibo Yang Xiaozong Zuo Decheng School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China

Reliability is one of the most critical properties of software *** deployment architecture is the allocation of system software components on host *** Architecture(SA) based software deployment models help to analyze reliability of different *** many approaches for architecture-based reliability estimation exist,little work has incorporated the influence of system deployment and hardware resources into reliability *** are many factors influencing system *** translating the multi-dimension factors into degree matrix of component dependence,we provide the definition of component dependence and propose a method of calculating system reliability of ***,the parameters that influence the optimal deployment may change during system *** existing software deployment architecture may be ill-suited for the given environment,and the system needs to be redeployed to improve *** approximate algorithm,A*_D,to increase system reliability is *** the number of components and host nodes is relative large,experimental results show that this algorithm can obtain better deployment than stochastic and greedy algorithms.

关键词： Software Architecture(SA) Software deployment System reliability component Redeploy

Purine alkaloids in tea plants:component,biosynthetic mechanism and genetic variation

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Beverage Plant Research 2022年第1期2卷 94-102页

作者： Shuran Zhang Jiqiang Jin Jiedan Chen Sezai Ercisli Liang Chen Key Laboratory of Biology Genetics and Breeding of Special Economic Animals and PlantsMinistry of Agriculture and Rural AffairsTea Research InstituteChinese Academy of Agricultural SciencesHangzhou 310008China Department of Horticulture Faculty of AgricultureAtaturk UniversityErzurum 25240Turke

The purine alkaloids,including caffeine,theobromine,and theacrine,are one of the most important quality and functional components of tea plants and commercial *** this paper,we review the component,biosynthetic mechanism and genetic variation of purine alkaloids in tea *** content of caffeine and theobromine in 403 accessions Chinese tea germplasms core collection preserved in the National Germplasm Hangzhou Tea Repository were analyzed using High Performance Liquid Chromatography(HPLC).The purine alkaloid profiles of different tea varieties,germplasm types,geographical origin,seasons,were *** naturally low caffeine or caffeine-free,high theobromine or high theacrine germplasms were identified and the possible biosynthetic mechanism of hypernormal purine alkaloid content in tea plants were partially *** Cleaved Amplified Polymorphic Sequences(CAPS)DNA markers were developed for the identification of purine alkaloid *** potential application of genetic engineering and DNA markers developed based on the low caffeine TCS1(tea caffeine synthesis gene)alleles for marker assisted selection(MAS),and cocoa tea and kucha in low caffeine/high theacrine tea cultivar breeding programs were also reviewed.

关键词： mechanism component urine

Modified Independent component Regression Method Without Prewhitening

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Journal of Harbin Institute of Technology(New Series) 2019年第4期26卷 50-57页

作者： Rong Guo Jimin Ye School of Mathematics and Statistics Xidian University

Independent component analysis(ICA) can reveal the essential underlying structure of data, and independent component regression(ICR) methods usually obtain better performance than other regression methods such as principal component regression. However, when existing ICR methods separate or extract independent components using prewhitened data, the backward propagation of inevitable prewhitened errors deteriorates the final linear prediction accuracy. To overcome this weakness, first, we proposed using weighted orthogonal constraint condition to replace the prewhitening of the data in ICA. Next, the statistical independence of ICs and the close relationship between ICs and quality variables are considered at the same time. Then, by combining the merits of improved ICR and ensemble ICR algorithm which solved the problem of selecting an appropriate nonquadratic function in ICA iteration procedure, a modified independent component regression(MICR) method that directly used the measured process data was proposed. Finally, three experimental results were used to validate excellent performance of modified algorithm.

关键词： independent component analysis weighted orthogonal constraint independent component regression prewhitened data

PRINCIPAL component ANALYSIS IN APPLICATION TO OBJECT ORIENTATION

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Geo-Spatial Information Science 2000年第3期3卷 76-78页

作者： WEI Yi S.MarshallWEI Yi,Ph.D.Candidate,University of Strathclyde,UKKEY WORDS principal component analysis(PCA) principal component(PC) observed samples eigenvector eigenvalue University of Strathclyde UK

This paper proposes a new method based on principal component analysis to find the direction of an object in any *** show that this method is fast,can be applied to objects with any pixel distribution and keep the ori... 详细信息

关键词： principal component analysis(PCA) principal component(PC) observed samples eigenvector eigenvalue

Application of component Technology to E-commerce System

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Geo-Spatial Information Science 2004年第4期7卷 308-310页

作者： ZHU Jianfeng ZHU Jianfeng, postgraduate, School of Information Management, Wuhan University, Luojia Hill, Wuhan 430072 Economic Information Management Department, Hubei Univisity of Economics, 33 Luoyu Road, Wuhan 430079, China. School of Information Management Wuhan University Wuhan Economic Information Managemen: Department Hubei University of Economics Wuhan China

At present E-commerce system tends to become more complex, and traditional system designing methods can not fufil the need of E-commerce system, thus requiring an effective methodas solution. With this concern, this paper introduces some concepts of component technology, then brings forward the new connotation and basic features of component technology through the analysis of its technological character. This paper finally discusses the application of component technology to E-commerce system.

关键词： E-commerce component interface internet