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基于排名的变量型主成分分析法在学生综合成绩评价中的应用 被引量:6
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作者 王剑宇 汤凤香 《佳木斯大学学报(自然科学版)》 CAS 2018年第5期777-780,共4页
对综合评价的方法进行了简要的介绍;采用主成分分析法,以某中学学生成绩为样本,基于各科成绩排名对学生综合成绩进行了评价,分析了其与原始成绩的统计关系。根据实际数据,利用变量型主成分分析法确定指标权重,进一步得到了学生综合成绩... 对综合评价的方法进行了简要的介绍;采用主成分分析法,以某中学学生成绩为样本,基于各科成绩排名对学生综合成绩进行了评价,分析了其与原始成绩的统计关系。根据实际数据,利用变量型主成分分析法确定指标权重,进一步得到了学生综合成绩的评价结果;利用主成分得分,对优势学科的判定方法进行了研究,明确了相关年级的优势学科,对师资力量的定位与学生的评价提供了依据。 展开更多
关键词 排名 变量成分分析 统计关系
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区域经济发展的需求因素分析 被引量:2
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作者 左继宏 胡树华 《统计与决策》 CSSCI 北大核心 2004年第4期14-15,共2页
关键词 区域经济 经济发展 需求因素 指标体系 变量主成分分析 样本成分分析 对应分析
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FTIR Spectroscopic Study of Broad Bean Diseased Leaves 被引量:2
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作者 李志永 刘刚 +5 位作者 李伦 欧全宏 赵兴祥 张黎 周湘萍 汪禄祥 《Agricultural Science & Technology》 CAS 2012年第11期2363-2366,2408,共5页
[Objective] The aim was to indentify diseased leaves of broad bean by vibra- tional spectroscopy. [Method] In this paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and norma... [Objective] The aim was to indentify diseased leaves of broad bean by vibra- tional spectroscopy. [Method] In this paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and normal leaves were studied using Fourier transform infrared spectroscopy combined with chemometrics. [Result] The spectra of the samples were similar, only with minor differences in absorption inten- sity of several peaks. Second derivative analyses show that the significant difference of all samples was in the range of 1 200-700 cm2. The data in the range of 1 200- 700 cm' were selected to evaluate correlation coefficients, hierarchical cluster analy- sis (HCA) and principal component analysis (PCA). Results showed that the correla- tion coefficients are larger than 0.928 not only between the healthy leaves, but also between the same diseased leaves. The values between healthy and diseased leaves, and among diseased leaves, are all declined. HCA and PCA yielded about 73.3% and 82.2% accuracy, respectively. [Conclusion] This study demonstrated that FTIR techniques might be used to detect crop diseases. 展开更多
关键词 FTIR spectroscopy Broad bean diseases Principal component analysis Cluster analysis
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Multivariate Statistical Process Monitoring of an Industrial Polypropylene Catalyzer Reactor with Component Analysis and Kernel Density Estimation 被引量:16
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作者 熊丽 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期524-532,共9页
Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the t... Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation (KDE) is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE(KPCA), and ICA with KDE,(KICA), are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator. 展开更多
关键词 multivariate statistical process monitoring principal comPonent analysis kermel density estimation POLYPROPYLENE catalyzer reactor fault detection data-driven tools
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改进的基于PCA的软件缺陷预测方法
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作者 杨雪 《南京工程学院学报(自然科学版)》 2008年第4期46-52,共7页
为了避免在变量多重情况下基于PCA的软件缺陷预测出现明显失误,对传统PCA方法的缺陷加以改进,利用UML软件工程组织网站上公布的某中等规模软件公司项目功能点数据,采用改进的PCA方法对项目综合性能进行软件缺陷预测,并与传统PCA方法的... 为了避免在变量多重情况下基于PCA的软件缺陷预测出现明显失误,对传统PCA方法的缺陷加以改进,利用UML软件工程组织网站上公布的某中等规模软件公司项目功能点数据,采用改进的PCA方法对项目综合性能进行软件缺陷预测,并与传统PCA方法的预测结果进行了对比.结果表明,改进的PCA方法对软件系统的综合性能有较好的预测能力. 展开更多
关键词 软件缺陷 软件缺陷预测 成分分析 变量多重 改进的成分分析
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Classification of Barley according to Harvest Year and Species by Using Mid-infrared Spectroscopy and Multivariate Analysis
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作者 Ajib Budour Fournier Frantz +2 位作者 Boivin Patrick Schmitt Marc Fick Michel 《Journal of Food Science and Engineering》 2014年第1期36-54,共19页
In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrare... In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrared Fourier transform spectroscopy FT-IR. The experimental dataset included barley from three harvest years, two barley species, 77 barley varieties, and two-row and six-row barley, from 16 cultivation sites. For each sample, the malt quality indices were also assessed according to European Brewing Convention (EBC) standards. Principal component analysis (PCA) was carried out on mean-centred, normalized and derivative spectra using 200/cm width spectral bands. The most informative spectral bands were observed in the 800-1,000/cm and 1,000-1,200/cm ranges. PCA revealed that barley harvested in 2010 and in 2011 had bands that were very close together, while 2009 harvest clearly displayed a difference in its quality. PCA made it possible to distinguish two species and confirmed that two-row winter barley quality was closer to two-row spring barley quality than to six-row winter barley. Results indicate that mid-infrared spectrometry (MIR) could be a very useful and rapid analytical tool to assess barley qualitative quality. 展开更多
关键词 Malting barley mean infrared spectroscopy principal components analysis.
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