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Relationship of public preferences and behavior in residential outdoor spaces using analytic hierarchy process and principal component analysis—a case study of Hangzhou City, China 被引量:7
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作者 SHI Jian-ren ZHAO Xiu-min +2 位作者 GE Jian HOKAO Kazunori WANG Zhu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第8期1372-1385,共14页
This study examined public attitudes concerning the value of outdoor spaces which people use daily. Two successive analyses were performed based on data from common residents and college students in the city of Hangzh... This study examined public attitudes concerning the value of outdoor spaces which people use daily. Two successive analyses were performed based on data from common residents and college students in the city of Hangzhou, China. First, citizens registered various items constituting desirable values of residential outdoor spaces through a preliminary questionnaire. The result proposed three general attributes (functional, aesthetic and ecological) and ten specific qualities of residential outdoor spaces. An analytic hierarchy process (AHP) was applied to an interview survey in order to clarify the weights among these attributes and qualities. Second, principal factors were extracted from the ten specific qualities with principal component analysis (PCA) for both the common case and the campus case. In addition, the variations of respondents’ groups were classified with cluster analysis (CA) using the results of the PCA. The results of the AHP application found that the public prefers the functional attribute, rather than the aesthetic attribute. The latter is always viewed as the core value of open spaces in the eyes of architects and designers. Fur-thermore, comparisons of ten specific qualities showed that the public prefers the open spaces that can be utilized conveniently and easily for group activities, because such spaces keep an active lifestyle of neighborhood communication, which is also seen to protect human-regarding residential environments. Moreover, different groups of respondents diverge largely in terms of gender, age, behavior and preference. 展开更多
关键词 public preference Open space Analytic hierarchy process (AHp principal component analysis (pca) Cluster analysis ca)
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Photobiomodulation inhibits the expression of chondroitin sulfate proteoglycans after spinal cord injury via the Sox9 pathway 被引量:1
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作者 Zhihao Zhang Zhiwen Song +12 位作者 Liang Luo Zhijie Zhu Xiaoshuang Zuo Cheng Ju Xuankang Wang Yangguang Ma Tingyu Wu Zhou Yao Jie Zhou Beiyu Chen Tan Ding Zhe Wang Xueyu Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期180-189,共10页
Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins ... Both glial cells and glia scar greatly affect the development of spinal cord injury and have become hot spots in research on spinal cord injury treatment.The cellular deposition of dense extracellular matrix proteins such as chondroitin sulfate proteoglycans inside and around the glial scar is known to affect axonal growth and be a major obstacle to autogenous repair.These proteins are thus candidate targets for spinal cord injury therapy.Our previous studies demonstrated that 810 nm photo biomodulation inhibited the formation of chondroitin sulfate proteoglycans after spinal cord injury and greatly improved motor function in model animals.However,the specific mechanism and potential targets involved remain to be clarified.In this study,to investigate the therapeutic effect of photo biomodulation,we established a mouse model of spinal cord injury by T9 clamping and irradiated the injury site at a power density of 50 mW/cm~2 for 50 minutes once a day for 7 consecutive days.We found that photobiomodulation greatly restored motor function in mice and down regulated chondroitin sulfate proteoglycan expression in the injured spinal cord.Bioinformatics analysis revealed that photobiomodulation inhibited the expression of proteoglycan-related genes induced by spinal cord injury,and versican,a type of proteoglycan,was one of the most markedly changed molecules.Immunofluorescence staining showed that after spinal cord injury,versican was present in astrocytes in spinal cord tissue.The expression of versican in primary astrocytes cultured in vitro increased after inflammation induction,whereas photobiomodulation inhibited the expression of ve rsican.Furthermore,we found that the increased levels of p-Smad3,p-P38 and p-Erk in inflammatory astrocytes were reduced after photobiomodulation treatment and after delivery of inhibitors including FR 180204,(E)-SIS3,and SB 202190.This suggests that Sma d 3/Sox9 and MAP K/Sox9 pathways may be involved in the effects of photobiomodulation.In summary,our findings show that photobiomodulation modulates the expression of chondroitin sulfate proteoglycans,and versican is one of the key target molecules of photo biomodulation.MAPK/Sox9 and Smad3/Sox9 pathways may play a role in the effects of photo biomodulation on chondroitin sulfate proteoglycan accumulation after spinal cord injury. 展开更多
关键词 chondroitin sulfate proteoglycans Erk MApK p38 pHOTOBIOMODULATION principal component analysis SMAD3 SOX9 spinal cord injury VERSIcaN
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Application of Multivariate Analysis for Identification of Pollution Sources in the Densu Delta Wetland in the Vicinity of a Landfill Site in Ghana 被引量:3
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作者 Juliet Osei Frank Kwakyi Nyame +5 位作者 Thomas Kaku Armah Shiloh Kwabena Osae Samuel Boakye Dampare Joseph Richmond Fianko Dickson Adomako Nash Bentil 《Journal of Water Resource and Protection》 2010年第12期1020-1029,共10页
Surface water samples collected from various sites in the Densu delta wetland, Ghana, were analyzed for pH, temperature, TDS, EC, turbidity, TSS, alkalinity, HCO3-, BOD, COD, Na, K, Mg, Ca, Cl, SO42-, PO4-P, NO3-N, Cr... Surface water samples collected from various sites in the Densu delta wetland, Ghana, were analyzed for pH, temperature, TDS, EC, turbidity, TSS, alkalinity, HCO3-, BOD, COD, Na, K, Mg, Ca, Cl, SO42-, PO4-P, NO3-N, Cr, Pb, Cd, Cu, Co and Fe using titration and Atomic Absorption Spectrometer (AAS). Multivariate statistical analyses such as cluster analysis (CA) and principal component analysis (PCA) were used to identify heavy metal pollution in the wetland area. Results from CA and PCA suggest positive relationships between the two analyses. Linear correlation analysis done also suggests similar relationships. Heavy metals were identified as originating from a common source in all the analyses. The hydrochemistry of the area appears to have been influenced, to a large extent, by dissolution/precipitation as well as numerous but subsistence small-scale agricultural activities that take place in the wetland environment. 展开更多
关键词 Densu DELTA WETLAND Surface Water pOLLUTION CLUSTER analysis (ca) principal component analysis (pca)
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Modeling and prediction of children’s growth data via functional principal component analysis 被引量:8
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作者 HU Yu HE XuMing +1 位作者 TAO Jian SHI NingZhong 《Science China Mathematics》 SCIE 2009年第6期1342-1350,共9页
We use the functional principal component analysis(FPCA) to model and predict the weight growth in children.In particular,we examine how the approach can help discern growth patterns of underweight children relative t... We use the functional principal component analysis(FPCA) to model and predict the weight growth in children.In particular,we examine how the approach can help discern growth patterns of underweight children relative to their normal counterparts,and whether a commonly used transformation to normality plays any constructive roles in a predictive model based on the FPCA.Our work supplements the conditional growth charts developed by Wei and He(2006) by constructing a predictive growth model based on a small number of principal components scores on individual's past. 展开更多
关键词 EIGENFUNCTION functional principal component analysis LMS method growth curve primary 62H25 Secondary 62p10
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基于PCA-CA合用的航班运行风险等级划分研究 被引量:3
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作者 谷润平 李景良 王岩韬 《安全与环境学报》 CAS CSCD 北大核心 2019年第6期1918-1927,共10页
为快速、直观、准确地划分航班运行风险等级,结合450组标准航班运行风险数据,首先根据主成分分析(PCA)从风险指标体系中提取主成分,实现风险指标降维;然后以主成分为变量,根据离差平方和法(Ward法)对航班进行聚类分析(CA);进而,结合主... 为快速、直观、准确地划分航班运行风险等级,结合450组标准航班运行风险数据,首先根据主成分分析(PCA)从风险指标体系中提取主成分,实现风险指标降维;然后以主成分为变量,根据离差平方和法(Ward法)对航班进行聚类分析(CA);进而,结合主成分得分图对各类航班的风险特征进行分析,划分风险等级,制定风险缓解控制措施;最后,对主成分方法应用前后在不同聚类数下的风险等级划分精度进行对比。结果表明:在航班运行风险指标体系中提取6个主成分时,累计反映原指标信息比例可达87.080%;PCACA合用后的风险等级划分精度有明显提升;聚类分类数为5时,效果最佳,风险等级划分精度可达到80.44%。综上证实基于PCA-CA合用的航班运行风险等级划分方法合理并可行。 展开更多
关键词 安全管理工程 航班运行 风险等级划分 主成分分析 聚类分析
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主成分分析(PCA)和聚类分析(CA)方法在SWB数据分析中的应用 被引量:2
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作者 罗先文 《玉溪师范学院学报》 2004年第12期25-30,共6页
在主观幸福感(SWB)的研究中,相关分析,回归或多元回归分析经常被用于数据的统计分析.考虑到SWB数据中通常包含着许多的变量,过于简单的分析处理方法将导致数据中信息的流失.本文将主成分分析(PCA)和聚类分析(CA)方法应用到SWB数据分析上... 在主观幸福感(SWB)的研究中,相关分析,回归或多元回归分析经常被用于数据的统计分析.考虑到SWB数据中通常包含着许多的变量,过于简单的分析处理方法将导致数据中信息的流失.本文将主成分分析(PCA)和聚类分析(CA)方法应用到SWB数据分析上,力求对SWB的原始数据有更加详细的了解和认识,并为今后类似问题的数据分析提供一个新的途经. 展开更多
关键词 主观幸福感(SWB) 主成分分析(pca) 聚类分析(ca) 文化体系
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Identification and spatial patterns of coastal water pollution sources based on GIS and chemometric approach 被引量:3
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作者 ZHOU Feng GUO Huai-cheng LIU Yong HAO Ze-jia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期805-810,共6页
Comprehensive and joint applications of GIS and chemometric approach were applied in identification and spatial patterns of coastal water pollution sources with a large data set (5 years (2000-2004), 17 parameters... Comprehensive and joint applications of GIS and chemometric approach were applied in identification and spatial patterns of coastal water pollution sources with a large data set (5 years (2000-2004), 17 parameters) obtained through coastal water monitoring of Southern Water Control Zone in Hong Kong. According to cluster analysis the pollution degree was significantly different between September-next May (the 1st period) and June-August (the 2nd period). Based on these results, four potential pollution sources, such as organic/eutrophication pollution, natural pollution, mineral/anthropic pollution and fecal pollution were identified by factor analysis/principal component analysis. Then the factor scores of each monitoring site were analyzed using inverse distance weighting method, and the results indicated degree of the influence by various potential pollution sources differed among the monitoring sites. This study indicated that hybrid approach was useful and effective for identification of coastal water pollution source and spatial patterns. 展开更多
关键词 source identification spatial pattern cluster analysis ca) principal component analysis (pca) inverse distance weighting (IDW) Hong Kong
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集成自编码与PCA的高炉多元铁水质量随机权神经网络建模 被引量:19
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作者 周平 张丽 +2 位作者 李温鹏 戴鹏 柴天佑 《自动化学报》 EI CSCD 北大核心 2018年第10期1799-1811,共13页
针对随机权神经网络(Random vector functional-link networks, RVFLNs)建模存在的过拟合和泛化能力差的问题,集成自编码(Autoencoder)和主成分分析(Principal component analysis, PCA)技术,提出一种新型的改进RVFLNs算法,即AE-P-RVFLN... 针对随机权神经网络(Random vector functional-link networks, RVFLNs)建模存在的过拟合和泛化能力差的问题,集成自编码(Autoencoder)和主成分分析(Principal component analysis, PCA)技术,提出一种新型的改进RVFLNs算法,即AE-P-RVFLNs算法,用于建立高炉多元铁水质量在线估计的NARX (Nonlinear autoregressive exogenous)模型.首先,为了尽可能挖掘实际复杂工业数据中的有用信息和充分揭示输入数据之间的内在关系,采用Autoencoder前馈随机网络技术训练建模输入数据,并将训练得到的输出权值作为后续RVFLNs的输入权值;然后,引入PCA技术对RVFLNs的高维隐层输出矩阵进行降维,避免隐层输出矩阵多重共线性问题,从而解决由于隐层节点过多导致模型过拟合的问题;最后,基于所提AE-P-RVFLNs算法建立某大型高炉多元铁水质量在线估计的NARX模型.工业实验和比较分析表明:采用本文算法建立的多元铁水质量在线估计模型可有效提高运算效率和估计精度,尤其是避免常规RVFLNs建模存在的过拟合问题. 展开更多
关键词 随机权神经网络 AE-p-RVFLNs 自编码 主成分分析 NARX建模 高炉炼铁 过拟合
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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran 被引量:1
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作者 Reza Ghezelbash Abbas Maghsoudi Mehrdad Daviran 《Acta Geochimica》 EI CAS CSCD 2019年第1期131-144,共14页
The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-el... The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits. 展开更多
关键词 GEOCHEMIcaL signature Concentration–area(C–A) fractal principal component analysis(pca) Student’s t-value Fuzzy mineral prospectivity modeling(MpM) prediction–area(p–A) pLOT
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基于PCA与LS-SVM的故障预测应用研究 被引量:2
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作者 张祎 《电脑知识与技术(过刊)》 2015年第4X期238-241,共4页
基于数据驱动的故障预测通过对故障特征的历史数据进行建模,对新的数据进行分类,达到故障识别的目的。由于故障数据的样本空间小,而故障特征的维度非常高,故障预测的建模呈现高维度建模困难的特点。针对这些问题,本文利用主成分分析结... 基于数据驱动的故障预测通过对故障特征的历史数据进行建模,对新的数据进行分类,达到故障识别的目的。由于故障数据的样本空间小,而故障特征的维度非常高,故障预测的建模呈现高维度建模困难的特点。针对这些问题,本文利用主成分分析结合最小二乘支持向量机对故障数据进行建模,并构建故障预测的分类模型。首先利用主成分分析方法对高维的故障特征数据进行降维处理,保留故障信息贡献较大的特征(维度),再利用最小二乘支持向量机对降维的样本故障数据进行分类训练,构造故障的分类模型。在不同特征的故障数据集上的测试表明,基于主成分分析故障预测预处理结合最小二乘支持向量机可以更为准确地对故障进行预测,且模型的构建时间较少。 展开更多
关键词 支持向量机 故障预测 主成分分析 降维
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Relationship of Soil Qualities to Maize Growth Under Increasing Phosphorus Supply in Acid Soils of Southern Cameroon
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作者 TCHIENKOUA M. JEMO +3 位作者 R. NJOMGANG C. NOLTE N. SANGINGA J. TAKOW 《Pedosphere》 SCIE CAS CSCD 2008年第5期645-652,共8页
A large array of soil properties influences plant growth response to phosphorus(P) fertilizer input in acid soils. We carried out a pot experiment using three contrasted acid soils from southern Cameroon with the foll... A large array of soil properties influences plant growth response to phosphorus(P) fertilizer input in acid soils. We carried out a pot experiment using three contrasted acid soils from southern Cameroon with the following main objectives:i) to assess the main soil causal factors of different maize(Zea mays L.) growth response to applied P and ii) to statistically model soil quality variation across soil types as well as their relationships to dry matter production. The soils used are classified as Typic Kandiudox(TKO) ,Rhodic Kandiudult(RKU) ,and Typic Kandiudult(TKU) . Analysis of variance,regression,and principal component analyses were used for data analysis and interpretation. Shoot dry matter yield(DMY) was significantly affected by soil type and P rate with no significant interaction. Predicted maximum attainable DMY was lowest in the TKO(26.2 g pot-1) as compared to 35.6 and 36.7 g pot-1 for the RKU and TKU,respectively. Properties that positively influenced DMY were the levels of inorganic NaHCO3-extractable P,individual basic cations(Ca,Mg,and K) ,and pH. Their effects contrasted with those of exchangeable Al and C/N ratio,which significantly depressed DMY. Principal component analysis yielded similar results,identifying 4 orthogonal components,which accounted for 84.7% of the total system variance(TSV) . Principal component 1 was identified as soil nutrient deficiency explaining 35.9% of TSV. This soil quality varied significantly among the studied soils,emerging as the only soil quality which significantly(P < 0.05) correlated with maize growth. The 2nd,3rd,and 4th components were identified as soil organic matter contents,texture,and HCl-extractable P,respectively. 展开更多
关键词 acid soil maize growth p supply principal component analysis soil quality
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向天果HPLC指纹图谱及特征成分含量测定研究
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作者 谢喆 孙云鹏 +2 位作者 金文芳 刘劲松 王国凯 《食品与药品》 CAS 2023年第6期481-487,共7页
目的 建立向天果高效液相色谱(HPLC)指纹图谱及2种柠檬苦素类成分含量测定方法。方法 采用KR100-5C18(250 mm×4.6 mm)色谱柱,以乙腈(A)-水(B)为流动相进行梯度洗脱,柱温30℃,流速1 ml/min,检测波长210 nm。采用《中药色谱指纹图谱... 目的 建立向天果高效液相色谱(HPLC)指纹图谱及2种柠檬苦素类成分含量测定方法。方法 采用KR100-5C18(250 mm×4.6 mm)色谱柱,以乙腈(A)-水(B)为流动相进行梯度洗脱,柱温30℃,流速1 ml/min,检测波长210 nm。采用《中药色谱指纹图谱相似度评价系统(2012版)软件》,结合聚类分析和主成分分析比较30批向天果色谱图,同时测定了向天果中swietenolide和swietwnine的含量。结果 建立了向天果HPLC指纹图谱,并对13个共有峰中的5个主要共有峰进行指认。30批向天果swietenolide和swietwnine的平均含量分别为14.28,10.74 mg/g。结论 本文所建立的指纹图谱和含量测定方法可用于向天果的质量控制。 展开更多
关键词 向天果 指纹图谱 聚类分析 主成分分析 柠檬苦素 含量测定
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新疆TASTE台阵拾震器方位角标定及其对SKS波分裂测量的影响
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作者 毛鹏宇 叶勃 +1 位作者 陈永顺 盖增喜 《北京大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第5期822-838,共17页
在对塔里木岩石圈地震台阵(TASTE)的66个宽频带流动台站数据进行严格约束基础上,利用3种国际上常用的方法——P波主成分分析法、P波切向最小能量法和Rayleigh波相关系数法,实现地震仪的拾震器方位角标定。3种方法得出的结果具有较高的... 在对塔里木岩石圈地震台阵(TASTE)的66个宽频带流动台站数据进行严格约束基础上,利用3种国际上常用的方法——P波主成分分析法、P波切向最小能量法和Rayleigh波相关系数法,实现地震仪的拾震器方位角标定。3种方法得出的结果具有较高的一致性(相关系数介于0.64~0.91之间),通过综合分析确定最终的地震仪拾震器方位角。其中62个台站地震仪的拾震器方向较稳定,且所有台站均没有出现南北反向、拾震器方位角随时间推移而发生系统性变化的情况。通过与磁偏角对比,发现有40个台站地震仪的拾震器方位角位于磁偏角的±3°范围内,说明TASTE台阵受到的外部干扰较小,台站部署质量较高。通过两个SKS波分裂实例,评估拾震器方位角对SKS波分裂测量产生的影响,论证了在地震学中进行拾震器方位角标定的必要性。 展开更多
关键词 塔里木盆地 拾震器方位角 p波主成分分析法 p波切向最小能量法 Rayleigh波相关系数法 磁偏角 SKS波分裂
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层叠P阶多项式主成分分析在轴承故障诊断中的应用 被引量:1
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作者 牟亮 王凯 +1 位作者 李彦 於辉 《振动与冲击》 EI CSCD 北大核心 2019年第2期25-32,共8页
针对传统滚动轴承故障特征提取及识别高度依赖先验知识及专家经验,导致其故障诊断的人工成本高及分类精度不够高的问题,提出一种层叠P阶多项式主成分分析方法实现滚动轴承故障的精确诊断。提出一种可适用于处理线性不可分数据的P阶多项... 针对传统滚动轴承故障特征提取及识别高度依赖先验知识及专家经验,导致其故障诊断的人工成本高及分类精度不够高的问题,提出一种层叠P阶多项式主成分分析方法实现滚动轴承故障的精确诊断。提出一种可适用于处理线性不可分数据的P阶多项式主成分分析法从滚动轴承的振动信号中自动学习去相关的低维特征;构建了层叠P阶多项式主成分分析网络,从去相关的低维特征中进一步增强学习更具可分辨性的特征,并通过反向优化过程,确保学习的特征不失真;采用K最近邻分类器对学习到的特征矢量进行分类,实现故障模式的辨识。通过滚动轴承故障数据库上的诊断试验验证了该方法的可靠性和有效性。 展开更多
关键词 层叠学习 层叠p阶多项式主成分分析(Sppca) 滚动轴承 故障诊断
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4种不同品种玫瑰精油的检测及成分分析
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作者 陶永霞 安比芳 +2 位作者 陈创业 乔桂芳 冯作山 《中国调味品》 CAS 北大核心 2024年第8期149-154,共6页
试验以大马士革玫瑰、紫枝玫瑰、丰花玫瑰、苦水玫瑰为研究对象,利用水蒸气蒸馏法从4种玫瑰中提取精油,采用气相色谱-质谱法(GC-MS)对不同品种玫瑰精油挥发性物质进行定性定量分析,并通过主成分分析(PCA)和聚类分析(CA)对玫瑰精油进行... 试验以大马士革玫瑰、紫枝玫瑰、丰花玫瑰、苦水玫瑰为研究对象,利用水蒸气蒸馏法从4种玫瑰中提取精油,采用气相色谱-质谱法(GC-MS)对不同品种玫瑰精油挥发性物质进行定性定量分析,并通过主成分分析(PCA)和聚类分析(CA)对玫瑰精油进行判定、区分和聚集。结果表明,GC-MS检测得到玫瑰精油含有65种挥发性物质,对其进行主成分分析,可以简化为3个主成分,前两个主成分的累计方差贡献率为81.952%,可反映玫瑰的大部分信息,通过主成分分析将4种玫瑰精油分为两大类:大马士革玫瑰精油和紫枝玫瑰精油为一类,丰花玫瑰精油和苦水玫瑰精油为一类。不同玫瑰品种挥发性物质组成多样,该研究以期为今后的精油提取和分析提供一定的理论基础。 展开更多
关键词 4种玫瑰精油 水蒸气蒸馏法 气相色谱-质谱法(GC-MS) 主成分分析(pca) 聚类分析(ca)
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基于化学模式识别技术的枳实HPLC定量指纹图谱研究 被引量:20
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作者 戚华文 徐鑫 +5 位作者 温柔 高德嵩 王超然 刘艳芳 金红利 梁鑫淼 《分析测试学报》 CAS CSCD 北大核心 2021年第1期72-78,共7页
建立了枳实的高效液相色谱(HPLC)指纹图谱分析方法。色谱柱为Tnature-ACCHROM C18色谱柱(4.6 mm×250 mm,5μm);以乙腈-0.5%甲酸水溶液为流动相进行梯度洗脱,结合液相色谱-四极杆飞行时间质谱(HPLC-QTOF-MS)联用技术对枳实指纹图谱... 建立了枳实的高效液相色谱(HPLC)指纹图谱分析方法。色谱柱为Tnature-ACCHROM C18色谱柱(4.6 mm×250 mm,5μm);以乙腈-0.5%甲酸水溶液为流动相进行梯度洗脱,结合液相色谱-四极杆飞行时间质谱(HPLC-QTOF-MS)联用技术对枳实指纹图谱中的共有峰进行鉴定;采用相似度评价、聚类分析(CA)、主成分分析(PCA)和正交偏最小二乘判别分析(OPLS-DA)对22批枳实进行数据分析及质量评价。结果显示:指纹图谱共标定12个共有峰,HPLC-QTOF-MS分析指认出11个成分;22批枳实样品的相似度在0.9以上;CA、PCA和OPLS-DA的分析结果一致,其中江西产地聚为一类,湖南和福建产地聚为一类,并筛选出橙皮苷、新橙皮苷和柚皮苷3个差异性质量标志物。所建立的枳实HPLC指纹图谱方法稳定、可靠,可为其质量控制提供参考依据。 展开更多
关键词 枳实 色谱指纹图谱 聚类分析(ca) 主成分分析(pca) 正交偏最小二乘判别分析(OpLS-DA)
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生地黄汤HPLC指纹图谱的建立及10种成分的含量测定 被引量:9
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作者 吴梦苑 樊强强 +4 位作者 王梅 翟秉涛 程江雪 邹俊波 郭东艳 《西北药学杂志》 CAS 2022年第4期7-14,共8页
目的建立生地黄汤高效液相色谱(high performance liquid chromatography,HPLC)指纹图谱,并测定其中10种成分的含量。方法用Shimadzu Shim-pack GIST C_(18)色谱柱(250 mm×4.6 mm,5μm),以乙腈(A)-1 mL·L^(-1)磷酸水溶液(B)... 目的建立生地黄汤高效液相色谱(high performance liquid chromatography,HPLC)指纹图谱,并测定其中10种成分的含量。方法用Shimadzu Shim-pack GIST C_(18)色谱柱(250 mm×4.6 mm,5μm),以乙腈(A)-1 mL·L^(-1)磷酸水溶液(B)为流动相进行梯度洗脱,流速为0.8 mL·min^(-1),柱温为40℃,检测波长为215 nm。用中药色谱指纹图谱相似度评价体系建立指纹图谱,分别用聚类分析、主成分分析和偏最小二乘法-判别分析对10批次生地黄汤指纹图谱进行分析,同时测定10种成分的含量,筛选出可能影响生地黄汤质量的因素。结果建立生地黄汤指纹图谱,10批样品之间的相似度在0.975~0.991范围内,共标出21个峰作为共有峰,指认出10个共有峰(梓醇、桃叶珊瑚苷、没食子酸、地黄苷D、毛蕊花糖苷、芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚);通过聚类分析将10批样品聚为3类;通过主成分分析和偏最小二乘法将样品分为3类;定量分析方法学考察符合要求,对10批样品中梓醇、桃叶珊瑚苷、没食子酸、地黄苷D、毛蕊花糖苷、芦荟大黄素、大黄酸、大黄素、大黄酚、大黄素甲醚的质量浓度进行了测定。结论建立生地黄汤指纹图谱并同时测定10种成分的含量,为生地黄汤的质量控制和评价提供较为全面的参考。 展开更多
关键词 生地黄汤 指纹图谱 标志性成分 聚类分析(ca) 主成分分析(pca) 偏最小二乘法-判别分析(pLS-DA)
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基于HPLC和多元统计分析的清热解毒口服液质量评价模式研究 被引量:3
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作者 朱伟堃 井改革 +2 位作者 赵蕊蕊 王素香 赵丹彤 《食品与药品》 CAS 2021年第6期493-498,共6页
目的建立同时测定清热解毒口服液中绿原酸、栀子苷、连翘苷、黄芩苷含量的方法,并综合评价其质量。方法采用高效液相色谱法(HPLC)同时测定清热解毒口服液中4种成分含量,并结合雷达图分析、聚类分析和主成分分析等多元统计分析,比较不同... 目的建立同时测定清热解毒口服液中绿原酸、栀子苷、连翘苷、黄芩苷含量的方法,并综合评价其质量。方法采用高效液相色谱法(HPLC)同时测定清热解毒口服液中4种成分含量,并结合雷达图分析、聚类分析和主成分分析等多元统计分析,比较不同企业样品的总体质量。结果含量测定方法学考察结果均符合有关要求,雷达图分析、聚类分析和主成分分析均将样品分为2类。结论本研究所建立的HPLC法结合多元统计分析,能较好地反映各企业清热解毒口服液的整体质量。 展开更多
关键词 清热解毒口服液 含量测定 高效液相色谱 雷达图分析 聚类分析 主成分分析
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中国数字地震台网(CDSN)单台站P波偏振分析 被引量:1
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作者 陈彦含 吴庆举 《地震》 CSCD 北大核心 2020年第4期49-62,共14页
偏振分析可以定量描述地震波的质点运动。P波质点运动在水平方向上发生偏振,使得传播方向会偏离台站与地震震源之间大圆弧的方向。P波偏振分析可以用来约束地下结构以及反映地震各向异性,提供与剪切波分裂等手段不同的证据。本文介绍并... 偏振分析可以定量描述地震波的质点运动。P波质点运动在水平方向上发生偏振,使得传播方向会偏离台站与地震震源之间大圆弧的方向。P波偏振分析可以用来约束地下结构以及反映地震各向异性,提供与剪切波分裂等手段不同的证据。本文介绍并使用主成分分析(Principle Component Analysis,PCA)的方法,计算了单一地震台的P波偏振,同时,利用谐和分析,对台站下方的各向异性进行了分析。将P波偏振分析应用到中国数字地震台网(China Digital Seismograph Network,CDSN)的四个台站10年左右的数据,筛选并分析了震相清晰、信噪比高的远震三分量初至P波的质点运动,拟合出四个台站接收到的地震事件后方位角与P波水平偏离角度之间的三角函数曲线,计算出拉萨台、昆明台下方上地幔各向异性的偏振方向分别为66°和57°,大致呈现北东东方向。 展开更多
关键词 p波偏振 中国数字地震台网 主成分分析 各向异性
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Quantitative Regionalization of W. Mujib-Wala Sub-Watersheds (Southern Jordan) Using GIS and Multivariate Statistical Techniques 被引量:2
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作者 Yahya Farhan Nisrin Al-Shaikh 《Open Journal of Modern Hydrology》 2017年第2期165-199,共35页
In arid and semi-arid watersheds, sustainable management of natural resources (i.e. land, water and ecological resources), and watershed management are crucial issues in applied morphometric studies. Geomorphometric p... In arid and semi-arid watersheds, sustainable management of natural resources (i.e. land, water and ecological resources), and watershed management are crucial issues in applied morphometric studies. Geomorphometric parameters and their interrelationships are of paramount importance in characterizing the morphology, topography, geology and structure, hydrological potential, and geomorphic evolution of such catchments. An analysis of spatial characteristics and morphological development of the demarcated 76 sub-watersheds related to W. Mujib-Wala catchment, was carried out using ASTER DEM and GIS. Multivariate statistical techniques such as Principal Component Analysis (PCA), Cluster Analysis (CA), and Discriminant Analysis (DA), were also employed to assess different aspects of drainage networks, and their morphometric properties. Principal Component Analysis (PCA) reduces the 22 morphometric parameters to five components, which explain 90.4% of total variance. The relationship of these components to the morphometric variables and to the individual sub-watersheds was evaluated, and then the degree of inter-correlation among the morphometric descriptors was explored. The 76 sub-watersheds were classified according to their individual relation to the components, and similarities in their morphometric characteristics. Regionalization of sub-watertsheds was achieved using hierarchical Cluster Analysis (CA). The validity of the resultant cluster groups was tested statistically by means of Discriminant Analysis. The present investigation provides information which highlights the benefit of geomorphometric analysis and multivariate statistics in modeling hydrological responses: i.e., surface runoff and sediment yield, hydrological assessment, water resources planning, and watershed management. Furthermore, the results can be useful for soil and water conservation planning, and assessment of flash floods potential. 展开更多
关键词 ASTER DEM MORpHOMETRIC Assessment principal component analysis (pca) Cluster analysis (ca) DISCRIMINANT analysis (DA) GIS
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