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主成分分析与聚类分析在奶牛评定方面的应用 被引量:8
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作者 刘桂苹 贾永全 曹宏伟 《黑龙江八一农垦大学学报》 2003年第3期86-89,共4页
利用主成分分析与聚类分析的方法对八五一一农场奶牛进行了评定,结果表明:利用主成分分析和聚类分析方法进行奶牛评定及分类是可行的。具有其它分析方法不具备的优点。应用此种分析方法进行奶牛评定表明,在奶牛评定的10个指标中,体高、... 利用主成分分析与聚类分析的方法对八五一一农场奶牛进行了评定,结果表明:利用主成分分析和聚类分析方法进行奶牛评定及分类是可行的。具有其它分析方法不具备的优点。应用此种分析方法进行奶牛评定表明,在奶牛评定的10个指标中,体高、尻角度和后房高度3个指标是影响奶牛评分的三个主要因素。 展开更多
关键词 成分分析:聚类分析方法 累积贡献率
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主成分分析在农村居民消费性支出研究中的应用 被引量:1
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作者 苗新利 郎英 杨俊 《中国商论》 2018年第35期69-71,共3页
基于主成分的评价模型,在损失较少信息的前提下,把多因素分析转化为几个主要综合因素分析,从而抓住主要矛盾,揭示事物内部变量之间的规律性,使问题简化,提高分析效率。本文运用主成分分析方法筛选出影响我国2016年各省市农村居民人均消... 基于主成分的评价模型,在损失较少信息的前提下,把多因素分析转化为几个主要综合因素分析,从而抓住主要矛盾,揭示事物内部变量之间的规律性,使问题简化,提高分析效率。本文运用主成分分析方法筛选出影响我国2016年各省市农村居民人均消费支出的主成分,再运用相应的聚类方法将消费支出水平相近的省市进行归类和分析。 展开更多
关键词 农村居民消费性支出主成分分析聚类分析
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安徽省乡村振兴水平测度与聚类分析 被引量:10
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作者 李刚 范鸿儒 《长春理工大学学报(社会科学版)》 2019年第5期104-109,共6页
采用2012~2017年安徽省乡村振兴的时间序列数据和2017年各地市的截面数据,从政治现代化、社会现代化、农民现代化和城乡融合发展四个方面建立因子分析模型,运用主成分及聚类分析实证研究了安徽省及其16个地市乡村振兴发展情况。研究发现... 采用2012~2017年安徽省乡村振兴的时间序列数据和2017年各地市的截面数据,从政治现代化、社会现代化、农民现代化和城乡融合发展四个方面建立因子分析模型,运用主成分及聚类分析实证研究了安徽省及其16个地市乡村振兴发展情况。研究发现:安徽省乡村振兴发展整体趋于上升态势,城乡融合不断加强,其中社会现代化、农民现代化与城乡融合发展能够有效抑制政治发展不充分对乡村振兴的不良影响。从静态发展的角度来看,安徽省乡村振兴的发展水平可分为水平较高、一般、较差三类,皖中、皖南城市的乡村振兴水平普遍高于皖北地区,此外,作为省会城市的合肥,乡村振兴综合排名第一,铜陵市是皖南地区社会现代化、政治现代化和城乡融合协调发展较好的城市。 展开更多
关键词 乡村振兴 指标体系 现代化 城乡融合 成分分析聚类分析
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南方大豆核心种质主要农艺及产量性状的表型多样性评价 被引量:7
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作者 王瑞珍 赵朝森 +3 位作者 程春明 邱丽娟 刘章雄 赵现伟 《大豆科学》 CSCD 北大核心 2010年第4期580-585,共6页
对南方大豆150份核心种质的15个主要农艺及产量性状进行表型多样性分析。结果表明:底荚高度、株高、有效分枝数的变异系数均在30%以上,单株粒数、单株荚数、百粒重、单株粒重、单位面积产量的变异系数均在20%以上;主成分分析结果表明,前... 对南方大豆150份核心种质的15个主要农艺及产量性状进行表型多样性分析。结果表明:底荚高度、株高、有效分枝数的变异系数均在30%以上,单株粒数、单株荚数、百粒重、单株粒重、单位面积产量的变异系数均在20%以上;主成分分析结果表明,前5个主成分对变异的累计贡献率达88.432%,而其数量性状的差异主要是由生育期结构性状引起的;不同性状的多样性指数不同,同一性状在不同生态区种群中的多样性也不同;经聚类分析,南方大豆核心种质7个生态区域种群可划分为3组;随着纬度的升高,不同来源地大豆种质平均单位面积产量呈先增加后降低的趋势;筛选到大豆优异种质12份,并提出了其在生产和育种上的应用前景。 展开更多
关键词 大豆 核心种质 多样性 成分分析 聚类分析
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东北东部城市竞争力评价 被引量:2
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作者 赵述 《商业时代》 北大核心 2013年第26期130-132,共3页
城市竞争力是指一个城市与其他城市相比所具有的积聚和转化资源、创造财富和提供服务以及辐射带动周边发展的现实和潜在的能力,是城市经济、社会、科技、文化、管理等水平和能力的综合体现。提高城市竞争力是推进城镇化进程的一个重要... 城市竞争力是指一个城市与其他城市相比所具有的积聚和转化资源、创造财富和提供服务以及辐射带动周边发展的现实和潜在的能力,是城市经济、社会、科技、文化、管理等水平和能力的综合体现。提高城市竞争力是推进城镇化进程的一个重要前提。在国家发改委和商务部的大力支持下,东北东部城市合作日益密切。本文从综合经济实力、科学教育卫生、基础设施环境、对外开放水平四个方面,选取19个指标构建城市竞争力评价指标体系,采用主成分分析法,计算东北东部城市竞争力得分和排名,根据聚类分析对城市类型进行划分和城市竞争力分析,提出提高东北东部城市竞争力、促进东北东部城市合作发展的建议,以期对今后的相关研究有所启发。 展开更多
关键词 城市竞争力 主成分分析聚类分析 东北东部
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Study on Phenological Character in Seedling Period of Introduced Populus deltoids Clones 被引量:2
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作者 唐洁 汤玉喜 +4 位作者 苏晓华 李永进 黄秦军 吴敏 杨艳 《Agricultural Science & Technology》 CAS 2014年第3期422-426,共5页
In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource ev... In order to provide directionally genetically improved breeding materials of poplar by exploring the phenological traits genetic variation level and its develop- ment potential of Populus deltoides and the resource evaluation was carried out; 8 phenological phases in seedling period were observed and analyzed of 60 Populus deltoids clones introduced from America. The results showed that: (1) there was obvious difference in phonological character among clones, especially in leaf-spread- ing peak stage and the end term of leaf-falling stage, with the largest variation co- efficient of 14.97% and the minimum of 3.83% respectively. (2) Leaf-spreading peak stage scattered but the end term of leaf-falling stage concentrated the most. The phonological character in early stage of seedling growth was the main factor influ- encing the length of growing season. (3) By principal component analysis, pheno- logical phases were classified into 3 typical periods, including germination stage, leaf-spreading peak stage and leaf-falling stage. (4) Totaling 60 clones were classi- fied into 4 types by using clustering analysis in phenological time variables of clones. 展开更多
关键词 Populus deltoids CLONE Phenological phase Principal component analysis Clustering analysis
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Application of PCA and HCA to the Structure-Activity Relationship Study of Fluoroquinolones 被引量:2
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作者 李小红 张现周 +2 位作者 程新路 杨向东 朱遵略 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期143-148,共6页
Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analy... Density functional theory (DFT) was used to calculate molecular descriptors (properties) for 12 fluoro-quinolone with anti-S.pneumoniae activity. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to reduce dimensionality and investigate in which variables should be more effective for classifying fluoroquinolones according to their degree of an-S.pneumoniae activity. The PCA results showed that the variables ELUMO, Q3, Q5, QA, logP, MR, VOL and △EHL of these compounds were responsible for the anti-S.pneumoniae activity. The HCA results were similar to those obtained with PCA.The methodologies of PCA and HCA provide a reliable rule for classifying new fluoroquinolones with antiS.pneumoniae activity. By using the chemometric results, 6 synthetic compounds were analyzed through the PCA and HCA and two of them are proposed as active molecules with anti-S.pneumoniae, which is consistent with the results of clinic experiments. 展开更多
关键词 Structure-activity relationship Density functional theory Principal component analysis Hierarchical cluster analysis
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基于可视化传感器阵列系统的肺癌标志物快速检测研究 被引量:4
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作者 侯长军 宋坤 +3 位作者 彭剑 霍丹群 董家乐 黄承洪 《传感器与微系统》 CSCD 北大核心 2012年第9期57-59,63,共4页
肺癌的早期快速诊断对于肺癌患者的治疗至关重要。针对肺癌患者所呼出的特定标志物,建立可视化传感器阵列系统,对4种肺癌标志物进行了实验研究。采用分层聚类分析、主成分分析的统计学方法对检测结果进行分析。对不同肺癌标志物、不同... 肺癌的早期快速诊断对于肺癌患者的治疗至关重要。针对肺癌患者所呼出的特定标志物,建立可视化传感器阵列系统,对4种肺癌标志物进行了实验研究。采用分层聚类分析、主成分分析的统计学方法对检测结果进行分析。对不同肺癌标志物、不同体积分数的样本在聚类分析中可以正确分类,且结构相似体积分数相近的样本能优先聚到一簇。利用主成分分析获得的前2个主成分所代表的肺癌标志物72.0%的信息量即可以实现不同类标志物样本区分。研究表明:这种可视化传感器阵列系统是一种快速有效的检测识别肺癌标志物的方法。 展开更多
关键词 可视化传感器阵列系统 肺癌标志物 检测 分层聚类分析:成分分析
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Study on Rhizome Crops by Fourier Transform Infrared Spectroscopy Combined with Wavelet Analysis
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作者 任静 刘刚 +4 位作者 赵兴祥 赵帅群 欧全宏 徐娟 胡见飞 《Agricultural Science & Technology》 CAS 2015年第7期1522-1526,共5页
In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieram... In order to distinguish 8 kinds of rhizome crops, the 40 samples were studied by Fourier transform infrared spectroscopy (FTIR) combined with wavelet transform (WT), principal component analysis (PCA) and hieramhical cluster analysis (HCA). The results showed that the infrared spectra were similar on the whole, but there were differences in peak position, peak shape and peak absorption intensity in the range of 1 800-700 cm-1. The infrared spectra in the range of 1 800-700 cm-1 were selected to perform continuous wavelet transform (CWT) and discrete wavelet transform (DWT). The 15th-Ievel decomposition coefficients of CWT and the 5=-level detail coefficients of DWT were classified by PCA and HCA. The cumulative contri- bution rates of the first three principal components of CWT and DWT were 93.12% and 89.78%, respectively. The accurate recognition rates of PCA and HCA were all 100%. It is proved that FTIR combined with WT can be used to distinguish different kinds of rhizome crops. 展开更多
关键词 FTIR Rhizome crop Wavelet transform Principal component analysis Hierarchical cluster analysis
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Morphological Diversity Analysis of Red-seed Watermelon (Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao) Germplasm Resources 被引量:1
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作者 柳唐镜 张棵 吴素萍 《Agricultural Science & Technology》 CAS 2013年第3期458-465,共8页
[Objective] This study aimed to analyze the morphological diversity of red- seed watermelon (Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao) germplasm resources. [Method] Multiple cluster analysis an... [Objective] This study aimed to analyze the morphological diversity of red- seed watermelon (Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao) germplasm resources. [Method] Multiple cluster analysis and principal components analysis on the morphological traits of 51 red-seed watermelon germplasm resources were carried out. [Result] The coefficient of variations (CVs) of 39 morphological traits in 51 red-seed watermelon idioplasm resources ranged from 5.37% to 66.95%, with an average of 22.87%. The average of Shannon diversity information indices was 1.55. Among them, the Shannon diversity information index of seed length was the highest (2.16) and that of seed shell figure pattern was the lowest (0.32). In ad- dition, the morphological diversity information indices of quantity characters were higher than that of quality characters. The principal components analysis revealed that the variance contribution rates of the first, second and third principal compo- nents were 19.49%, 15.32% and 9.55%, respectively. Cluster analysis divided the 51 materials into three broad branches based on the morphological traits. There was only one material in the fist branch and two in the second branch, and all the three materials were wild. The other 48 materials were divided into the third branch and all of them were cultivars. [Conclusion] This study provided a theoretical basis for the protection and utilization of red-seed watermelon resources. 展开更多
关键词 Red-seed watermelon Germplasm resources Morphological diversity Cluster analysis Principal component analysis
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Study on Trace Elements in Rehmannia glutinosa Libosch. by Principal Component Analysis and Clustering Analysis
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作者 申明金 陈丽 曹洪斌 《Agricultural Science & Technology》 CAS 2013年第12期1764-1768,共5页
[Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering anal... [Objective] This study aimed to investigate the trace elements in Rehman- nia glutinosa Libosch. by using principal component analysis and clustering analysis. [Method] Principal component analysis and clustering analysis of R. glutinosa medicinal materials from different sources were conducted with contents of six trace elements as indices. [Result] The principal component analysis could comprehen- sively evaluate the quality of R. glutinosa samples with objective results which was consistent with the results of clustering analysis. [Conclusion] Principal component analysis and clustering analysis methods can be used for the quality evaluation of Chinese medicinal materials with multiple indices. 展开更多
关键词 Rehmannia glutinosa Libosch. (Radix Rehmanniae) Trace elements Principal component analysis Clustering analysis
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不同贮藏条件对麦冬药材质量的影响 被引量:6
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作者 谈梦霞 陈佳丽 +3 位作者 邹立思 刘训红 唐仁茂 马继梅 《中药材》 CAS 北大核心 2018年第11期2592-2598,共7页
目的:基于多种成分同时测定结合统计分析考察不同贮藏条件对麦冬药材质量的影响。方法:采用超快速液相色谱-三重四极杆/线性离子阱质谱(UFLC-QTRAP-MS/MS)法同时测定不同贮藏条件下麦冬药材中甾体皂苷、高异黄酮、氨基酸和核苷类共29种... 目的:基于多种成分同时测定结合统计分析考察不同贮藏条件对麦冬药材质量的影响。方法:采用超快速液相色谱-三重四极杆/线性离子阱质谱(UFLC-QTRAP-MS/MS)法同时测定不同贮藏条件下麦冬药材中甾体皂苷、高异黄酮、氨基酸和核苷类共29种成分的含量,结合聚类分析和主成分分析,对不同贮藏条件下麦冬样品进行综合评价。结果:29种化合物在一定浓度范围内均呈现良好的线性关系,r均大于0.9990;精密度、重复性和稳定性良好;平均加样回收率为97.64%~102.98%,RSD均小于5%。麦冬的适宜贮藏条件为以麻袋为外包装存放于阴凉库。结论:该研究建立的方法准确、可靠,可用于麦冬药材内在质量的综合评价,同时可为麦冬药材适宜储藏条件的优选提供基础资料。 展开更多
关键词 麦冬 贮藏条件 UFLC-QTRAP-MS/MS 聚类分析成分分析
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Comparative Analysis of Morphologic Traits of 50 Large-flowered Chrysanthemum Varieties
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作者 沈珍 毛燕 +2 位作者 吴德智 袁伟 杨旭 《Agricultural Science & Technology》 CAS 2016年第2期317-322,共6页
With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized bl... With 50 large-flowered Chrysanthemum varieties from germplasm nursery of Wunaoshan Forest Farm in Macheng City as research objects, 64 morphological traits were investigated by field experiments adopting randomized block design. The morphological differences were observed by uniformity analysis, variability analysis, principal component analysis and cluster analysis. The result showed that the vari- able coefficients of 59 traits were greater than 15%; the contribution rate of first seven principal components reached 81.45%; and it was found by clustering analy- sis that the 50 germplasm resources could be divided into four clusters with obvious morphological differences, and plant type could be used as an index for classifica- tion. 展开更多
关键词 Large-flowered Chrysanthemum Morphologic traits Variability analysis Principal component analysis Clustering analysis
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气相-离子迁移谱结合化学计量学方法快速区分不同年份酿造白酒 被引量:18
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作者 张敏敏 路岩翔 +4 位作者 赵志国 崔莉 闫慧娇 王晓 赵恒强 《食品工业科技》 CAS 北大核心 2021年第14期226-232,共7页
目的:建立了气相色谱-离子迁移谱(Gas chromatography-ion mobility spectroscopy, GC-IMS)技术结合化学计量学分析快速区分不同年份酱香型白酒的方法。方法:采用GC-IMS技术对多批次不同年份的酱香型酿造白酒样本中挥发性有机物进行分析... 目的:建立了气相色谱-离子迁移谱(Gas chromatography-ion mobility spectroscopy, GC-IMS)技术结合化学计量学分析快速区分不同年份酱香型白酒的方法。方法:采用GC-IMS技术对多批次不同年份的酱香型酿造白酒样本中挥发性有机物进行分析,通过对比挥发性有机物含量差异快速生成指纹图谱,并通过PCA-CA分析实现样本的快速区分。结果:将白酒中检测到的化合物峰利用NIST 2014气相保留指数数据库与IMS迁移时间数据库进行准确的二维定性后共鉴别出包含单体和二聚体在内的共53个挥发性有机物。挥发性有机物指纹图谱对比结果显示不同年份样本中所含化合物的种类和含量差异较大,采用PCA分析可以实现不同年份原酒和老熟酒的正确区分,采用主成分分析-聚类分析(Principal component analysis-cluster analysis, PCA-CA)处理结果进一步明确了区分结果的准确性。结论:该方法直观、快速、准确,为酿造白酒的年份区分提供了方法和技术支持。 展开更多
关键词 气相离子迁移谱技术(GC-IMS) 化学计量学 成分分析-聚类分析(PCA-CA) 酿造白酒 年份
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Morphological Study of Ficus deltoidea Jack in Malaysia
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作者 Nor Asiah Awang Sayed M.Zain Hasan Mohammad Shafie B.Shafie 《Journal of Agricultural Science and Technology(B)》 2013年第2期144-150,共7页
Ficus deltoidea Jack (Moraceae) or Mas Cotek is a small shrub with a great morphological variation. Measurement of 40 morphological traits had been done on 50 accessions to find the most significant characters that ... Ficus deltoidea Jack (Moraceae) or Mas Cotek is a small shrub with a great morphological variation. Measurement of 40 morphological traits had been done on 50 accessions to find the most significant characters that enable differentiation being done according to its variety groups. The data were analyzed with principal component analysis (PCA) and cluster analysis (CA) using cluster software package programme to produce the scatter diagram and dendrogram relationship of the taxa. The results showed that there were 25 morphological characters having the value of factor analysis greater than 0.60 from its principal component (PC) with the Eigen value greater than 1.0. 16 out of 40 morphological characters had been identified as having high values of correlation coefficient ranging from -0.783 to 0.890. The analysis showed that the most responsible characters in grouping the samples into different groups are the shape and size of leaf, number and color of dots on the leaf surface and characters of syconium. The scatter diagram of the accessions on the PC1 against PC2 showed six major groups. The dendrogram displayed the relationship among the accessions and within the dissimilarity distance = 19, it classified the samples into five major groups. Observation on F. deltoidea resulted in the findings of high variability among the accessions. The most significant characters in grouping accessions are the shapes of leaf base (BL), shape of leaf apex (SA), ratio of lamina width to lamina length (R), dots color at the lower midrib (DLM), color of young syconium (CYS), color of mature syconium (CMS) and the number of syconium on trees (DST). This study provides basic information for introduction of some particular traits and effective conservation of the species breeding programme. The morphological traits were found to be useful for the diversity studies and in identifying the variation. The actual figures of F. deltoidea obtained through this study enable comparison being done to the previous and in future study. Hence, the varieties that are extinct could be recognised. 展开更多
关键词 Ficus deltoidea cluster analysis DIVERSITY morphological variability principal component analysis
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