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Establishment of HPLC Fingerprint, Cluster Analysis and Principle Component Analysis of Citri Reticulatae Pericarpium Viride 被引量:4
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作者 Beibei JIN Xiangping PEI Huizhen LIANG 《Medicinal Plant》 CAS 2019年第1期69-73,共5页
[Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination wa... [Objectives] This study aimed to establish HPLC fingerprint and conduct cluster analysis and principle component analysis for Citri Reticulatae Pericarpium Viride. [Methods] Using the HPLC method, the determination was performed on XSelect~&#x00AE; HSS T3-C_(18) column with mobile phase of acetonitrile-0.5% acetic acid solution(gradient elution) at the flow rate of 1.0 mL/min. The detection wavelength was 360 nm. The column temperature was 25℃. The sample size was 10 μL. With peak of hesperidin as the reference, HPLC fingerprints of 10 batches of Citri Reticulatae Pericarpium Viride were determined. The similarity of the 10 batches of samples was evaluated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(2012 edition) to determine the common peaks. Cluster analysis and principal component analysis were performed by using SPSS 17.0 statistical software. [Results] The HPLC fingerprints of the 10 batches of medicinal materials had total 11 common peaks, and the similarity was 0.919-1.000, indicating that the chemical composition of the 10 batches of medicinal materials was consistent. There were 11 common components in the 10 batches of medicinal materials, but their contents were different. When the Euclidean distance was 20, the 10 batches of samples were divided into two categories, S4 in the first category, and the others in the second one. When the Euclidean distance was 5, the second category could be further divided into two sub-categories, S1 and S10 in one sub-category, and S2, S3, S5, S6, S7, S8 and S9 in the other one. The principle component analysis showed that cumulative contribution rate of the two main component factors was 92.797%, and the comprehensive score of S7 was the highest with the best quality. [Conclusions] The results of HPLC fingerprinting, cluster analysis and principle component analysis can provide reference for the quality control of Citri Reticulatae Pericarpium Viride. 展开更多
关键词 Citri Reticulatae Pericarpium Viride HPLC FINGERPRINT CLUSTER analysis principle component analysis
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Celiac Disease Seen with the Eyes of the Principle Component Analysis and Analyse Des Données
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作者 Cleto Corposanto Beba Molinari Susanna Neuhold 《Open Journal of Statistics》 2015年第3期211-222,共12页
This paper aims to deepen the quality of life of people with celiac disease with a focus on compliance to the diet through Principle Component Analysis and Analyse des Données. In particular, we will try to under... This paper aims to deepen the quality of life of people with celiac disease with a focus on compliance to the diet through Principle Component Analysis and Analyse des Données. In particular, we will try to understand whether these analyzes are also applicable in the context of research web2.0 carried out with web-survey. 展开更多
关键词 CELIAC DISEASE Web-Survey principle component analysis Analyse DES Données
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Transformer’s Condition Assessment Method Based on Combination of Cloud Matter Element and Principal Component Analysis 被引量:1
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作者 Qianli Hong Jiantao Zhang +4 位作者 Qing Xie Shaodong Liang Yuqin Xu Si Li Weitao Hu 《Energy and Power Engineering》 2017年第4期659-666,共8页
With the development of power grid, as one of the key equipment, the transformer’s condition assessment method has always receive attention from experts, scholars concern more and more about the method’s practicalit... With the development of power grid, as one of the key equipment, the transformer’s condition assessment method has always receive attention from experts, scholars concern more and more about the method’s practicality and reliability. In the traditional condition assessment method, due to the characteristics of the transformer’s complex structure, the assessment system is not comprehensive enough, or the assessment system is too complex, the indexes are not easy to quantify, such problems are emerging. The traditional method is complex and the degree of quantification is not enough. Therefore it is necessary to propose a condition assessment method that is easy to carry out the condition assessment work and does not affect the assessment results. In this paper, we propose a method to assess the state of the transformer’s complex structure. First, we establish a comprehensive assessment system, then apply the method of principal component analysis to optimize the index system, and then use the theory of cloud-matter-element. Finally the reliability and rationality of the method are verified by an example. 展开更多
关键词 TRANSFORMER Assessment Method principle component analysis CLOUD Model
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GAUSSIAN PRINCIPLE COMPONENTS FOR NONLOCAL MEANS IMAGE DENOISING
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作者 Li Xiangping Wang Xiaotian Shi Guangming 《Journal of Electronics(China)》 2011年第4期539-547,共9页
NonLocal Means(NLM),taking fully advantage of image redundancy,has been proved to be very effective in noise removal.However,high computational load limits its wide application.Based on Principle Component Analysis(PC... NonLocal Means(NLM),taking fully advantage of image redundancy,has been proved to be very effective in noise removal.However,high computational load limits its wide application.Based on Principle Component Analysis(PCA),Principle Neighborhood Dictionary(PND) was proposed to reduce the computational load of NLM.Nevertheless,as the principle components in PND method are computed directly from noisy image neighborhoods,they are prone to be inaccurate due to the presence of noise.In this paper,an improved scheme for image denoising is proposed.This scheme is based on PND and uses preprocessing via Gaussian filter to eliminate the influence of noise.PCA is then used to project those filtered image neighborhood vectors onto a lower-dimensional space.With the preproc-essing process,the principle components computed are more accurate resulting in an improved de-noising performance.A comparison with some NLM based and state-of-art denoising methods shows that the proposed method performs well in terms of Peak Signal to Noise Ratio(PSNR) as well as image visual fidelity.The experimental results demonstrate that our method outperforms existing methods both subjectively and objectively. 展开更多
关键词 Image denoising NonLocal Means(NLM) Gaussian filter principle component analysis(PCA)
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Online prediction of network-level public transport demand based on principle component analysis
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作者 Cheng Zhong Peiling Wu +1 位作者 Qi Zhang Zhenliang Ma 《Communications in Transportation Research》 2023年第1期62-71,共10页
Online demand prediction plays an important role in transport network services from operations,controls to management,and information provision.However,the online prediction models are impacted by streaming data quali... Online demand prediction plays an important role in transport network services from operations,controls to management,and information provision.However,the online prediction models are impacted by streaming data quality issues with noise measurements and missing data.To address these,we develop a robust prediction method for online network-level demand prediction in public transport.It consists of a PCA method to extract eigen demand images and an optimization-based pattern recognition model to predict the weights of eigen demand images by making use of the partially observed real-time data up to the prediction time in a day.The prediction model is robust to data quality issues given that the eigen demand images are stable and the predicted weights of them are optimized using the network level data(less impacted by local data quality issues).In the case study,we validate the accuracy and transferability of the model by comparing it with benchmark models and evaluate the robustness in tolerating data quality issues of the proposed model.The experimental results demonstrate that the proposed Pattern Recognition Prediction based on PCA(PRP-PCA)consistently outperforms other benchmark models in accuracy and transferability.Moreover,the model shows high robustness in accommodating data quality issues.For example,the PRP-PCA model is robust to missing data up to 50%regardless of the noise level.We also discuss the hidden patterns behind the network level demand.The visualization analysis shows that eigen demand images are significantly connected to the network structure and station activity variabilities.Though the demand changes dramatically before and after the pandemic,the eigen demand images are consistent over time in Stockholm. 展开更多
关键词 Network-level demand prediction Data quality issues Eigen demand image Pattern recognition principle component analysis
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Block Principle Component Analysis with Lp-norm for Robust and Sparse Modelling 被引量:3
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作者 TANG Ganyi LU Guifu 《Journal of Shanghai Jiaotong university(Science)》 EI 2018年第3期398-403,共6页
Block principle and pattern classification component analysis (BPCA) is a recently developed technique in computer vision In this paper, we propose a robust and sparse BPCA with Lp-norm, referred to as BPCALp-S, whi... Block principle and pattern classification component analysis (BPCA) is a recently developed technique in computer vision In this paper, we propose a robust and sparse BPCA with Lp-norm, referred to as BPCALp-S, which inherits the robustness of BPCA-L1 due to the employment of adjustable Lp-norm. In order to perform a sparse modelling, the elastic net is integrated into the objective function. An iterative algorithm which extracts feature vectors one by one greedily is elaborately designed. The monotonicity of the proposed iterative procedure is theoretically guaranteed. Experiments of image classification and reconstruction on several benchmark sets show the effectiveness of the proposed approach. 展开更多
关键词 block principle component analysis(BPCA) LP-NORM robust modelling sparse modelling
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Multiple Factorial Analysis of Symbolic Data 被引量:3
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作者 Barnabé Tang Ahanda Jean Gérard Aghoukeng Jiofack +1 位作者 Romain Germain Nzangué Gilbert Hapi Mbiakop 《Applied Mathematics》 2012年第12期2148-2154,共7页
This document presents an extension of the multiple factorial analysis to symbolic data and especially to space data. The analysis makes use of the characteristic coding method to obtain active individuals and the rec... This document presents an extension of the multiple factorial analysis to symbolic data and especially to space data. The analysis makes use of the characteristic coding method to obtain active individuals and the reconstitutive coding method for additional individuals in order to conserve the variability of assertion objects. Traditional analysis methods of the main components are applied to coded objects. Certain interpretation aids are presented after the coding process. This method was applied to poverty data. 展开更多
关键词 SYMBOLIC OBJECT ASSERTION OBJECT MULTIPLE FACTORIAL analysis principle components analysis Poverty
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Genetic background analysis and breed evaluation of Yiling yellow cattle 被引量:1
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作者 XU Ling ZHANG Wen-gang +12 位作者 LI Jun-ya ZHU De-jiang XU Xiao-cheng TIAN Yan-zi XIONG Xiong GUO Ai-zhen CAO Bing-hai NIU Hong ZHU Bo WANG Ze-zhao LIANG Yong-hu SHEN Hong-xue CHEN Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2246-2256,共11页
Traditionally, Chinese indigenous cattle is geographically widespread. The present study analyzed based on genome-wide variants to evaluate the genetic background among 157 individuals from four representative indigen... Traditionally, Chinese indigenous cattle is geographically widespread. The present study analyzed based on genome-wide variants to evaluate the genetic background among 157 individuals from four representative indigenous cattle breeds of Hubei Province of China: Yiling yellow cattle (YL), Bashan cattle (BS), Wuling cattle (WL), Zaobei cattle (ZB), and 21 indi- viduals of Qinchuan cattle (QC) from the nearby Shanxi Province of China. Linkage disequilibrium (LD) analysis showed the LD of YL was the lowest (~=0.32) when the distance between markers was approximately 2 kb. Principle component analysis (PCA), and neighbor-joining (NJ)-tree revealed a separation of Yiling yellow cattle from other geographic nearby local cattle breeds. In PCA plot, the YL and QC groups were segregated as expected; moreover, YL individuals clustered together more obviously. In the N J-tree, the YL group formed an independent branch and BS, WL, ZB groups were mixed. We then used the FST statistic approach to reveal long-term selection sweep of YL and other 4 cattle breeds. According to the selective sweep, we identified the unique pathways of YL, associated with production traits. Based on the results, it can be proposed that YL has its unique genetic characteristics of excellence resource, and it is an indispensable cattle breed in China. 展开更多
关键词 Yiling yellow cattle breed evaluation principle component analysis neighbor-joining tree
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Improvement of tissue analysis and classification using optical coherence tomography combined with Raman spectroscopy 被引量:1
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作者 Chih-Hao Liu Ji Qi +4 位作者 Jing Lu Shang Wang Chen Wu Wei-Chuan Shih Kirill V.Larin 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2015年第4期10-19,共10页
Optical coherence tomography(OCT)provides significant advantages of high resolution(approaching the histopathology level)realtime imaging of tsess without use of contrast agents.Based on these advantages,the microstru... Optical coherence tomography(OCT)provides significant advantages of high resolution(approaching the histopathology level)realtime imaging of tsess without use of contrast agents.Based on these advantages,the microstructural features of tumors can be visualized and detected intra-operatively.However,it is still not clinically accepted for tumor margin delin-eation due to poor specificity and accuracy.In contrast,Raman spectroscopy(RS)can obtain tissue information at the molecular level,but does not provide real-time inaging capability.Therefore,combining OCT and RS could provide synergy.To this end,we present a tissue analysis and dassification method using both the slope of OCT intensity signal Vs depth and the principle components from the RS spectrum as the indicators for tissuse characterization.The goal of this study was to understand prediction accuracy of OCT and combined OCT/RS method for dassification of optically similar tisues and organs.Our pilot experiments were performed on mouse kidneys,livers,and small intestines(SIs).The prediction accuracy with five-fold cross validation of the method has been evaluated by the support vector machine(SVM)method.The results demonstrate that tissue characterization based on the OCT/RS method was superior compared to using OCT structural information alone.This combined OCT/RS method is potentially useful as a noninvasive optical biopsy technique for rapid and automatic tissue characterization during surgery. 展开更多
关键词 OCT signal slope principle component analysis multi-support vector machine Raman spectra
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Comprehensive Evaluation and Prediction of the Effectiveness of H_(2)O_(2)- assisted Na_(2)CO_(3)Pretreatment of Corn Stover Using Multivariate Analysis 被引量:2
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作者 Xiaoyan Feng Xuejin Xie +4 位作者 Yidong Zhang Guang Yu Chao Liu Bin Li Qiu Cui 《Paper And Biomaterials》 CAS 2021年第2期1-15,共15页
In this study,multivariate analysis methods,including a principal component analysis(PCA)and partial least square(PLS)analysis,were applied to reveal the inner relationship of the key variables in the process of H_(2)... In this study,multivariate analysis methods,including a principal component analysis(PCA)and partial least square(PLS)analysis,were applied to reveal the inner relationship of the key variables in the process of H_(2)O_(2)-assisted Na_(2)CO_(3)(HSC)pretreatment of corn stover.A total of 120 pretreatment experiments were implemented at the lab scale under different conditions by varying the particle size of the corn stover and process variables.The results showed that the Na_(2)CO_(3) dosage and pretreatment temperature had a strong influence on lignin removal,whereas pulp refining instrument(PFI)refining and Na_(2)CO_(3) dosage played positive roles in the final total sugar yield.Furthermore,it was found that pretreatment conditions had a more significant impact on the amelioration of pretreatment effectiveness compared with the properties of raw corn stover.In addition,a prediction of the effectiveness of the corn stover HSC pretreatment based on a PLS analysis was conducted for the first time,and the test results of the predictability based on additional pretreatment experiments proved that the developed PLS model achieved a good predictive performance(particularly for the final total sugar yield),indicating that the developed PLS model can be used to predict the effectiveness of HSC pretreatment.Therefore,multivariate analysis can be potentially used to monitor and control the pretreatment process in future large-scale biorefinery applications. 展开更多
关键词 lignocellulose pretreatment corn stover Na_(2)CO_(3) principle component analysis partial least square analysis
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Correlation analysis of stem hardness traits with fiber and yield-related traits in core collections of Gossypium hirsutum 被引量:1
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作者 RAZA Irum HU Daowu +13 位作者 AHMAD Adeel LI Hongge HE Shoupu NAZIR Mian Faisal WANG Xiaoyang JIA Yinhua PAN Zhaoe ZHANG Peng YASIR Muhammad IQBAL Muhammad Shahid GENG Xiaoli WANG Liru PANG Baoyin DU Xiongming 《Journal of Cotton Research》 2021年第1期66-75,共10页
Background:Stem hardness is one of the major influencing factors for plant architecture in upland cotton(Gossypium hirsutum L.).Evaluating hardness phenotypic traits is very important for the selection of elite lines ... Background:Stem hardness is one of the major influencing factors for plant architecture in upland cotton(Gossypium hirsutum L.).Evaluating hardness phenotypic traits is very important for the selection of elite lines for resistance to lodging in Gossypium hirsutum L.Cotton breeders are interested in using diverse genotypes to enhance fiber quality and high-yield.Few pieces of research for hardness and its relationship with fiber quality and yield were found.This study was designed to find the relationship of stem hardness traits with fiber quality and yield contributing traits of upland cotton.Results:Experiments were carried out to measure the bending,acupuncture,and compression properties of the stem from a collection of upland cotton genotypes,comprising 237 accessions.The results showed that the genotypic difference in stem hardness was highly significant among the genotypes,and the stem hardness traits(BL,BU,AL,AU,CL,and CU)have a positive association with fiber quality traits and yield-related traits.Statistical analyses of the results showed that in descriptive statistics result bending(BL,BU)has a maximum coefficient of variance,but fiber length and fiber strength have less coefficient of variance among the genotypes.Principal component analysis(PCA)trimmed quantitative characters into nine principal components.The first nine principal components(PC)with Eigenvalues>1 explained 86%of the variation among 237 accessions of cotton.Both 2017 and 2018,PCA results indicated that BL,BU,FL,FE,and LI contributed to their variability in PC1,and BU,AU,CU,FD,LP,and FWPB have shown their variability in PC2.Conclusion:We describe here the systematic study of the mechanism involved in the regulation of enhancing fiber quality and yield by stem bending strength,acupuncture,and compression properties of G.hirsutum. 展开更多
关键词 BENDING Compression ACUPUNCTURE principle component analysis Stem hardness
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Application of Principle Component Analysis and Logistic Regression in Analyzing miRNA Markers of Brain Arteriovenous Malformation
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作者 蒋路 黄俊 +2 位作者 张志君 杨国源 王永亭 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第6期641-645,共5页
Brain arteriovenous malformation(BAVM) is frequently described as vascular malformation. Although computer tomography(CT), magnetic resonance imaging(MRI) and angiography can clearly detect lesions, there are no diagn... Brain arteriovenous malformation(BAVM) is frequently described as vascular malformation. Although computer tomography(CT), magnetic resonance imaging(MRI) and angiography can clearly detect lesions, there are no diagnostic biological markers of BAVM available. Current study demonstrated that micro RNA(mi RNA)showed a feasible marker for vascular disease. To find key correlations between these mi RNAs and the onset of BAVM, we carried out chip analysis of serum mi RNAs by identifying 18 potential markers of BAVM. We then constructed a principle component analysis and logistic regression(PCA-LR) model to analyze the 18 mi RNAs collected from 77 patients. Another 9 independent samples were used to test the resulting model. The results showed that mi RNAs hsa-mir-126-3p and hsa-mir-140 are important protective factors, while hsa-mir-338 is a dominating risk factor, all of which have stronger correlation with BAVM than others. We also compared the testing results using PCA-LR model with those using LR model. The comparison revealed that PCA-LR model is better in predicting the disease. 展开更多
关键词 brain arteriovenous malformation(BAVM) microRNAs(miRNAs) principle component analysis(PCA) logistic regression(LR)
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Statistical Analysis and Evaluation of the Economic Development in Shaanxi Province
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作者 Xu GUO Chunxiang ZHAO Xinrong YAN 《Asian Agricultural Research》 2014年第4期24-28,共5页
Based on 8 indicators of economic development and according to the economic situation of cities in Shaanxi Province,this paper analyzes the data using PCA( Principle Component Analysis) and FA( Factor Analysis) with t... Based on 8 indicators of economic development and according to the economic situation of cities in Shaanxi Province,this paper analyzes the data using PCA( Principle Component Analysis) and FA( Factor Analysis) with the help of R software.Using the test of Kendal's W coefficient of concordance,the consistency of results from both methods is tested.Finally,Cluster Analysis is used to classify the results and some advices are proposed for the development of cites in Shaanxi Province. 展开更多
关键词 principle component analysis FACTOR analysis Kenda
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FEATURE-EXTRACT ANALYSIS OF SERIAL ANALYSIS OF GENE EXPRESSION DATA
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作者 Su Hongquan Zhu Yisheng 《Journal of Electronics(China)》 2010年第6期848-852,共5页
Serial Analysis of Gene Expression (SAGE) is a powerful tool to analyze whole-genome expression profiles. SAGE data, characterized by large quantity and high dimensions, need reducing their dimensions and extract feat... Serial Analysis of Gene Expression (SAGE) is a powerful tool to analyze whole-genome expression profiles. SAGE data, characterized by large quantity and high dimensions, need reducing their dimensions and extract feature to improve the accuracy and efficiency when they are used for pattern recognition and clustering analysis. A Poisson Model-based Kernel (PMK) was proposed based on the Poisson distribution of the SAGE data. Kernel Principle Component Analysis (KPCA) with PMK was proposed and used in feature-extract analysis of mouse retinal SAGE data. The computa-tional results show that this algorithm can extract feature effectively and reduce dimensions of SAGE data. 展开更多
关键词 Serial analysis of Gene Expression (SAGE) Poisson distribution Kernel methods principle component analysis (PCA)
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Cluster Analysis of Electrical Behavior
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作者 Lin Liu 《Journal of Computer and Communications》 2015年第5期88-93,共6页
In this paper, we apply clustering analysis of data mining into power system. We adapt K-means clustering algorithm to analyze customer load, analyzing similar behavior between customer of electricity, and we adapt pr... In this paper, we apply clustering analysis of data mining into power system. We adapt K-means clustering algorithm to analyze customer load, analyzing similar behavior between customer of electricity, and we adapt principal component analysis to get the clustering result visible, Simulation and analysis using matlab, and this well verify cluster rationality. The conclusion of this paper can provide important basis to the peak for the power system, stable operation the power system security. 展开更多
关键词 K-MEANS CLUSTERING analysis principle component analysis The POWER System
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Robust Principal Component Test in Gross Error Detection and Identification
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作者 高倩 阎威武 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第5期553-558,共6页
Principle component analysis (PCA) based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal c... Principle component analysis (PCA) based chi-square test is more sensitive to subtle gross errors and has greater power to correctly detect gross errors than classical chi-square test. However, classical principal com- ponent test (PCT) is non-robust and can be very sensitive to one or more outliers. In this paper, a Huber function liked robust weight factor was added in the collective chi-square test to eliminate the influence of gross errors on the PCT. Meanwhile, robust chi-square test was applied to modified simultaneous estimation of gross error (MSEGE) strategy to detect and identify multiple gross errors. Simulation results show that the proposed robust test can reduce the possibility of type Ⅱ errors effectively. Adding robust chi-square test into MSEGE does not obviously improve the power of multiple gross error identification, the proposed approach considers the influence of outliers on hypothesis statistic test and is more reasonable. 展开更多
关键词 gross error detection and identification chi-square test ROBUST principle component analysis (PCA) modified simultaneous estimation of gross error (MSEGE)
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Mathematical theory of signal analysis vs. complex analysis method of harmonic analysis
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作者 QIAN Tao ZHANG Li-ming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第4期505-530,共26页
We present recent work of harmonic and signal analysis based on the complex Hardy space approach.
关键词 Mobius transform Blaschke form mono-component Hardy space adaptive Fourier decomposi-tion rational approximation rational orthogonal system time-frequency distribution digital signal processing uncertainty principle higher dimensional signal analysis in several complex variables and the Clifford algebrasetting.
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基于PCA-BP神经网络的巷道通风摩擦阻力系数预测模型
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作者 高科 吕航宇 +1 位作者 戚志鹏 刘玉姣 《矿业安全与环保》 CAS 北大核心 2024年第1期7-13,共7页
根据实测巷道通风摩擦阻力系数数据的特点,建立了主成分分析PCA-BP神经网络预测模型。采用PCA法对影响巷道通风摩擦阻力系数的支护类型、断面形状、巷道宽、巷道高、支护部分周边长、巷道断面积和巷道长度7个因素进行降维。将降维后因... 根据实测巷道通风摩擦阻力系数数据的特点,建立了主成分分析PCA-BP神经网络预测模型。采用PCA法对影响巷道通风摩擦阻力系数的支护类型、断面形状、巷道宽、巷道高、支护部分周边长、巷道断面积和巷道长度7个因素进行降维。将降维后因素的贡献率进行排序筛选,得到3个主成分指标(F_(1)、F_(2)和F_(3)),作为BP神经网络输入层的神经元。利用实测数据对PCA-BP神经网络模型进行训练和测试,并将测试结果与支持向量机回归(SVM)模型和BP神经网络模型的测试结果进行对比,结果显示:全因素的BP神经网络预测模型和SVM预测模型的平均精度分别为92.9420%、93.0235%,而PCA-BP预测模型的平均精度达到了96.4325%。PCA-BP神经网络模型不但简化了网络结构,更提高了网络的泛化能力,使预测误差更小、精度更高,为更准确地获得巷道通风摩擦阻力系数提供了一种有效的方法。 展开更多
关键词 矿井通风 巷道通风摩擦阻力系数 预测模型 PCA-BP神经网络 主成分分析 影响因素
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基于近红外光谱技术鉴别丹参产地及其伪品
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作者 张延莹 程子航 《中国当代医药》 CAS 2024年第27期4-8,共5页
目的探讨应用近红外光谱技术结合化学计量学算法对不同产地丹参及其伪品的鉴别效果。方法收集陕西、山东、四川、河北等9个产地的265批丹参样品,以及市场常见的续断、牛蒡根和甘西鼠尾3种丹参伪品61批,利用SabIR漫反射光纤探头采集样品... 目的探讨应用近红外光谱技术结合化学计量学算法对不同产地丹参及其伪品的鉴别效果。方法收集陕西、山东、四川、河北等9个产地的265批丹参样品,以及市场常见的续断、牛蒡根和甘西鼠尾3种丹参伪品61批,利用SabIR漫反射光纤探头采集样品粉末的近红外漫反射光谱,并采用多元散射校正、标准正则变换、S-G平滑、Norris平滑、一阶微分及二阶微分等对光谱进行预处理。应用TQ Analyst分析系统,采用主成分分析结合马氏距离的判别分析方法,确定主成分数,建立丹参产地鉴别和真伪鉴别模型,并采用四重交叉验证测试模型预测性能。结果采用MSC+一阶+Norris的光谱预处理方式,确定最佳主成分数为10,建立模型并经过验证,产地鉴别准确率达到98%以上,真伪鉴别准确率达到100%。结论该方法可快速、准确鉴别丹参产地及其伪品,是对现有丹参鉴别方法的科学补充。 展开更多
关键词 近红外光谱 丹参 主成分分析 判别分析
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7份羊茅属种质芽期抗旱性评价 被引量:1
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作者 周晨烨 李培英 +6 位作者 孙宗玖 张勇娟 于冰洁 郑丽 周磊 许莹月 李有政 《种子》 北大核心 2024年第2期111-119,共9页
为了探究羊茅属种质芽期对逆境的胁迫能力,以沟羊茅新品系(FV)与紫羊茅常用品种传奇(CQ)、草原(CY)、梦神(MS)、北方(BF)、玉山(YS)和多花(DH)为材料,采用不同浓度PEG-6000(0、5%、10%、15%、20%、25%)模拟干旱胁迫,在芽期测定了发芽率... 为了探究羊茅属种质芽期对逆境的胁迫能力,以沟羊茅新品系(FV)与紫羊茅常用品种传奇(CQ)、草原(CY)、梦神(MS)、北方(BF)、玉山(YS)和多花(DH)为材料,采用不同浓度PEG-6000(0、5%、10%、15%、20%、25%)模拟干旱胁迫,在芽期测定了发芽率、发芽势、活力指数、胚根长、胚芽长、根芽比等萌发指标,分析干旱对其种子萌发的影响,并结合主成分分析、隶属函数分析、聚类分析等对其抗旱性进行评价。结果表明,高浓度PEG(20%~25%)显著降低了羊茅属种质的发芽势、发芽率、发芽指数、活力指数、胚根长、胚根长及根芽比,而5%~15%PEG则因种质的差异而变化趋势有所不同,其中0~10%PEG对FV、BF、YS的发芽率、发芽势、活力指数及发芽指数具有显著的引发作用;综合评价表明,主成分分析将7个相对单项性状指标降维成2个新的综合指标,累积贡献率达85.06%;以新合成的综合指标为依据,采用隶属函数法结合聚类分析,将7份羊茅属种质分为三类,其中,FV、CQ和BF的抗旱能力较强,CY及YS的抗旱能力一般,而MS、DH的抗旱能力较弱。 展开更多
关键词 羊茅属 芽期 抗旱性 主成分分析 隶属函数法 PEG胁迫
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