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Analysis of optical axis deviation caused by structural stiffness in equatorial telescopes
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作者 Haibo Li Runfu Peng +2 位作者 Chenggang Shu Yong Bi Shaoming Hu 《Astronomical Techniques and Instruments》 CSCD 2024年第4期203-210,共8页
The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures.A comprehensive analysis during the design process can reduce the reliance of... The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures.A comprehensive analysis during the design process can reduce the reliance of a telescope on advanced control technologies,thereby improving its economic feasibility.Although full-system finite element analyses are reliable,they are encumbered by significant time requirements and limitations in covering all possible telescope orientations.Therefore,we propose an efficient and comprehensive analytical method to evaluate the optical axis deviation of equatorial telescopes across a full range of angles.To address the challenge of ensuring that the analysis covers all possible positions of an equatorial telescope,based on a model from SiTian project,we analyze the optical axis deviations caused by the fork arm at 25 different angles and then use fitting methods to obtain results for all angles.Based on the analysis results of the optical axis deviation caused by the stiffness of the optical tube in the horizontal position,we derive the results for the tube at any position using geometric relationships.Finally,we calculate the coupling factors and combine these impacts.Furthermore,we identify six discrete feature points to reflect possible telescope orientations and conduct comprehensive finite element analyses.The results are in alignment with those acquired through a comprehensive computational approach. 展开更多
关键词 Astronomical instrumentation Telescopes Equatorial mounts Multivariate analysis
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Multivariate Analysis of Community Structure Variation of Plankton and Zoobenthos in Municipal Polluted River
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作者 麦戈 利锋 +2 位作者 吴昌华 段志鹏 曾祥云 《Agricultural Science & Technology》 CAS 2012年第8期1776-1780,共5页
[Objective] The plankton and macrobenthos samples in municipal polluted river were analyzed by different methods, so as to explore the method suitable for biological data analysis in heavy polluted area. [Method] Shan... [Objective] The plankton and macrobenthos samples in municipal polluted river were analyzed by different methods, so as to explore the method suitable for biological data analysis in heavy polluted area. [Method] Shannon-Wiener diversity index, cluster analysis of multivariate statistical analysis and MDS (Non-matric Multi- dimentional Scaling)analysis were used to analyze biological data of phytoplankton, zooplankton and Zoobenthos collected from the representative municipal polluted river in Pearl River Delta. The sediment samples were also collected to determine. Pb, Cd, Hg, Cr, As, Cu, Ni, Zn, as well as CODe, and NH3-N of porewater. Hakanson potential ecological risk index method was used to evaluate the ecological risk. [Re- suit] Shannon-Wiener diversity index analysis results can not effectively reflect the difference of pollution status of various stations in heavy polluted area; despite the presence of some problems, multivariate analysis method is superior to the Shannon-Wiener diversity index method in biological monitoring of heavy polluted river in the city. [Conclusion] The paper provided theoretical basis for biological data analysis in heavy polluted area. 展开更多
关键词 Municipal polluted river PLANKTON Multivariate analysis Shannon-Wiener diversity index
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Analysis of risk factors for central venous port failure in cancer patients 被引量:12
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作者 Ching-Chuan Hsieh Hsu-Huei Weng +4 位作者 Wen-Shih Huang Wen-Ke Wang Chiung-Lun Kao Ming-Shian Lu Chia-Siu Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第37期4709-4714,共6页
AIM: To analyze the risk factors for central port failure in cancer patients administered chemotherapy, using univariate and multivariate analyses. METHODS: A total of 1348 totally implantable venous access devices (T... AIM: To analyze the risk factors for central port failure in cancer patients administered chemotherapy, using univariate and multivariate analyses. METHODS: A total of 1348 totally implantable venous access devices (TIVADs) were implanted into 1280 cancer patients in this cohort study. A Cox proportional hazard model was applied to analyze risk factors for failure of TIVADs. Log-rank test was used to compare actuarial survival rates. Infection, thrombosis, and surgical complication rates (χ2 test or Fisher's exact test) were compared in relation to the risk factors. RESULTS: Increasing age, male gender and openended catheter use were signifi cant risk factors reducing survival of TIVADs as determined by univariate and multivariate analyses. Hematogenous malignancy decreased the survival time of TIVADs; this reduction was not statistically signifi cant by univariate analysis [hazard ratio (HR) = 1.336, 95% CI: 0.966-1.849, P = 0.080)]. However, it became a signifi cant risk factor by multivariate analysis (HR = 1.499, 95% CI: 1.079-2.083, P = 0.016) when correlated with variables of age, sex and catheter type. Close-ended (Groshong) catheters had a lower thrombosis rate than open-ended catheters (2.5% vs 5%, P = 0.015). Hematogenous malignancy had higher infection rates than solid malignancy (10.5% vs 2.5%, P < 0.001). CONCLUSION: Increasing age, male gender, openended catheters and hematogenous malignancy were risk factors for TIVAD failure. Close-ended catheters had lower thrombosis rates and hematogenous malignancy had higher infection rates. 展开更多
关键词 Central venous port CHEMOTHERAPY Risk factor Cancer patient Multivariate analysis
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Prognostic analysis and comparison of colon cancer in Han and Hui patients 被引量:6
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作者 Mei Zhang Qu-Chuan Zhao +3 位作者 Yan-Peng Liu Lei Yang Hong-Ming Zhu Jagadish K Chhetri 《World Journal of Gastroenterology》 SCIE CAS 2014年第17期5082-5086,共5页
AIM: To investigate the relevant prognostic factors and their differences between colorectal cancer (CRC) patients of Chinese Han and Hui ethnicities in the Beijing region.
关键词 Colon cancer Colorectal cancer Han patients Hui patients PROGNOSIS Multivariate analysis
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Groundwater quality assessment using multivariate analysis,geostatistical modeling, and water quality index(WQI): a case of study in the Boumerzoug-El Khroub valley of Northeast Algeria 被引量:4
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作者 Oualid Bouteraa Azeddine Mebarki +2 位作者 Foued Bouaicha Zeineddine Nouaceur Benoit Laignel 《Acta Geochimica》 EI CAS CSCD 2019年第6期796-814,共19页
In this study,the analytical data set of 26 groundwater samples from the alluvial aquifer of Boumerzoug-E1 khroub valley has been processed simultaneously with Multivariate analysis,geostatistical modeling,WQI,and geo... In this study,the analytical data set of 26 groundwater samples from the alluvial aquifer of Boumerzoug-E1 khroub valley has been processed simultaneously with Multivariate analysis,geostatistical modeling,WQI,and geochemical modeling.Cluster analysis identified three main water types based on the major ion contents,where mineralization increased from group 1 to group 3.These groups were confirmed by FA/PCA,which demonstrated that groundwater quality is influenced by geochemical processes(water-rock interaction)and human practice(irrigation).The exponential semivariogram model WQI.Groundwater chemistry has a strong spatial structure for Mg,Na,Cl,and NO3,and a moderate spatial structure for EC,Ca,K,HCO3,and SO4.Water quality maps generated using ordinary Kriging are consistent with the HCA and PCA results.All water groups are supersaturated with respect to carbonate minerals,and dissolution of kaolinite and Ca-smectite is one of the processes responsible for hydrochemical evolution in the area. 展开更多
关键词 GROUNDWATER Multivariate analysis Geostatistical modeling Geochemical modeling MINERALIZATION Ordinary Kriging
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Construction of Inorganic Elemental Fingerprint and Multivariate Statistical Analysis of Marine Traditional Chinese Medicine Meretricis concha from Rushan Bay 被引量:6
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作者 WU Xia ZHENG Kang +2 位作者 ZHAO Fengjia ZHENG Yongjun LI Yantuan 《Journal of Ocean University of China》 SCIE CAS 2014年第4期712-716,共5页
Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental... Meretricis concha is a kind of marine traditional Chinese medicine(TCM), and has been commonly used for the treatment of asthma and scald burns. In order to investigate the relationship between the inorganic elemental fingerprint and the geographical origin identification of Meretricis concha, the elemental contents of M. concha from five sampling points in Rushan Bay have been determined by means of inductively coupled plasma optical emission spectrometry(ICP-OES). Based on the contents of 14 inorganic elements(Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, and Zn), the inorganic elemental fingerprint which well reflects the elemental characteristics was constructed. All the data from the five sampling points were discriminated with accuracy through hierarchical cluster analysis(HCA) and principle component analysis(PCA), indicating that a four-factor model which could explain approximately 80% of the detection data was established, and the elements Al, As, Cd, Cu, Ni and Pb could be viewed as the characteristic elements. This investigation suggests that the inorganic elemental fingerprint combined with multivariate statistical analysis is a promising method for verifying the geographical origin of M. concha, and this strategy should be valuable for the authenticity discrimination of some marine TCM. 展开更多
关键词 Meretricis concha traditional Chinese medicine inorganic elemental fingerprint multivariate statistical analysis Rushan Bay
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Volatile profile and multivariant analysis of Sanhuang chicken breast in combination with Chinese 5-spice blend and garam masala 被引量:4
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作者 Rani Andaleeb Danni Zhang +2 位作者 Shui Jiang Yin Zhang Yuan Liu 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期57-68,共12页
Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are rou... Sanhuang chicken is a popular native breed in China and well-known for delicious flavour.Spices could enhance the chicken meat flavour and work well in preservation.Chinese 5-spice blend(CS)and garam masala(GM)are routinely using spices in China and Pakistan,respectively.The flavour profiles of Sanhuang chicken breast(CB)and its blends with CS and GM were obtained by electronic nose(E-nose),solid-phase microextraction gas chromatography-mass spectrometry(SPME GC-MS)and GC-ion mobility spectrometry(GC-IMS).Principal component analysis(PCA)efficiently discriminated the aroma profiles of three chicken formulations.The GC-chromatographs revealed the significant aroma alterations of chicken breast meat after marination with spices.Aldehydes were the major contributors of chicken aroma,while most of the aromatic hydrocarbons were generated by spices.Almost all chicken key-compounds produced by oxidation reaction were either reduced or eliminated by marination,showing the antioxidation capacity of spices leading to meat preservation.GC-IMS is not only a rapid and comprehensive detection method,but also proved to be more sensitive than GC-MS.The substantial role of both traditional spices in enhancing flavour quality of chicken meat,and their exposure as functional ingredients in Chinese and Pakistan cuisines could lead to the cross-cultural meat trade opportunities. 展开更多
关键词 Chicken breast Chinese 5-spice blend Garam masala Volatile compounds Qualitative techniques Multivariant analysis
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Comprehensive multivariate grey incidence degree based on principal component analysis 被引量:6
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作者 Ke Zhang Yintao Zhang Pinpin Qu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期840-847,共8页
To overcome the too fine-grained granularity problem of multivariate grey incidence analysis and to explore the comprehensive incidence analysis model, three multivariate grey incidences degree models based on princip... To overcome the too fine-grained granularity problem of multivariate grey incidence analysis and to explore the comprehensive incidence analysis model, three multivariate grey incidences degree models based on principal component analysis (PCA) are proposed. Firstly, the PCA method is introduced to extract the feature sequences of a behavioral matrix. Then, the grey incidence analysis between two behavioral matrices is transformed into the similarity and nearness measure between their feature sequences. Based on the classic grey incidence analysis theory, absolute and relative incidence degree models for feature sequences are constructed, and a comprehensive grey incidence model is proposed. Furthermore, the properties of models are researched. It proves that the proposed models satisfy the properties of translation invariance, multiple transformation invariance, and axioms of the grey incidence analysis, respectively. Finally, a case is studied. The results illustrate that the model is effective than other multivariate grey incidence analysis models. 展开更多
关键词 grey system multivariate grey incidence analysis behavioral matrix principal component analysis (PCA).
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Analysis of fatty acid composition of sea cucumber Apostichopus japonicus using multivariate statistics 被引量:2
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作者 徐勤增 高菲 +1 位作者 许强 杨红生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第6期1314-1319,共6页
Fatty acids(FAs) provide energy and also can be used to trace trophic relationships among organisms.Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months.We examined fatty acid... Fatty acids(FAs) provide energy and also can be used to trace trophic relationships among organisms.Sea cucumber Apostichopus japonicus goes into a state of aestivation during warm summer months.We examined fatty acid profiles in aestivated and non-aestivated A.japonicus using multivariate analyses(PERMANOVA,MDS,ANOSIM,and SIMPER).The results indicate that the fatty acid profiles of aestivated and non-aestivated sea cucumbers differed significantly.The FAs that were produced by bacteria and brown kelp contributed the most to the differences in the fatty acid composition of aestivated and nonaestivated sea cucumbers.Aestivated sea cucumbers may synthesize FAs from heterotrophic bacteria during early aestivation,and long chain FAs such as eicosapentaenoic(EPA) and docosahexaenoic acid(DHA) that produced from intestinal degradation,are digested during deep aestivation.Specific changes in the fatty acid composition of A.japonicus during aestivation needs more detailed study in the future. 展开更多
关键词 fatty acid (FAs) Apostichopusjaponicus AESTIVATION multivariate analysis
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ASSESSMENT OF LOCAL INFLUENCE IN MULTIVARIATE ANALYSIS 被引量:2
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作者 石磊 王学仁 《Acta Mathematica Scientia》 SCIE CSCD 1996年第3期257-264,165+266-270,共14页
A recent method for assessing the local influence is introduced by Cook(1986), in which the normal curvature of the influence graph based on the likelihood displacement is used to monitor the influence of small pertur... A recent method for assessing the local influence is introduced by Cook(1986), in which the normal curvature of the influence graph based on the likelihood displacement is used to monitor the influence of small perturbation. Since then this method has been applied to various kind of models. However, the local influence in multivariate analysis is still an unexplored area because the influence for many statistics in multivariate analysis is not convenient to handle based on the Cook's likelihood displacement. In this paper, we suggest a method with a slight modification in Cook's approach to assess the local influence of small perturbation on a certain statistic. The local influence of the perturbation on eigenvalue and eigenvector of variance-covariance matrix in theoretical and sample version is assessed, some results for the other statistics in multivariate analysis such as generalized variance, canonical correlations are studied. Finally, two examples are analysed for illustration. 展开更多
关键词 multivariate analysis normal curvature perturbation scheme local influence
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Surgical mortality in patients with malignant obstructive jaundice: a multivariate discriminant analysis 被引量:3
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作者 Xi-Chun Han Jin-Long Li Gang Han the Department of Surgery, Second Hospital, Jilin University, Changchun 130041, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2003年第3期435-440,共6页
OBJECTIVE: To estimate the operative mortality in patients with malignant obstructive jaundice. METHODS: Twelve risk factors were analyzed using multivariate discriminant analysis in 90 patients who had been operated ... OBJECTIVE: To estimate the operative mortality in patients with malignant obstructive jaundice. METHODS: Twelve risk factors were analyzed using multivariate discriminant analysis in 90 patients who had been operated on. RESULTS: Operative mortality was significantly related to the following factors: age, duration of jaundice, packed RBC volume, white blood cell count and concentration of blood urine nitrogen; it was not significantly related to diseases and types of operation. The following formula was obtained: packed RBC volume×0.09954-age×0. 04018-blood urine nitrogen×0. 23693-duration of jaundice× 2. 07388-WBC count×0. 21118+5. 26593. With this formula, an operative mortality of 77. 8% was predicted. CONCLUSION: With a positive value from the formula, the patient should be operated on; otherwise non-operative treatment is advocated. 展开更多
关键词 malignant obstructive jaundice postoperative mortality multivariate discriminant analysis
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Metabolomics-based comparative analysis of the effects of host and environment on Viscum coloratum metabolites and antioxidative activities 被引量:2
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作者 Rui-Zhen Zhang Jing-Tao Zhao +4 位作者 Wei-Qing Wang Rong-Hua Fan Rong Rong Zhi-Guo Yu Yun-Li Zhao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2022年第2期243-252,共10页
Viscum coloratum(Kom.)Nakai is a well-known medicinal hemiparasite widely distributed in Asia.The synthesis and accumulation of its metabolites are affected by both environmental factors and the host plants,while the ... Viscum coloratum(Kom.)Nakai is a well-known medicinal hemiparasite widely distributed in Asia.The synthesis and accumulation of its metabolites are affected by both environmental factors and the host plants,while the latter of which is usually overlooked.The purpose of this study was to comprehensively evaluate the effects of host and habitat on the metabolites in V.coloratum through multiple chemical and biological approaches.The metabolite profile of V.coloratum harvested from three different host plants in two habitats were determined by multiple chemical methods including high-performance liquid chromatography-ultraviolet(HPLC-UV),gas chromatography-flame ionization detector(GC-FID)and ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-QTOF/MS).The differences in antioxidant efficacy of V.coloratum were determined based on multiple in vitro models.The multivariate statistical analysis and data fusion strategy were applied to analyze the differences in metabolite profile and antioxidant activity of V.coloratum.Results indicated that the metabolite profile obtained by various chemical approaches was simultaneously affected by host and environment factors,and the environment plays a key role.Meanwhile,three main differential metabolites between two environment groups were identified.The results of antioxidant assay indicated that the environment has greater effects on the biological activity of V.coloratum than the host.Therefore,we conclude that the integration of various chemical and biological approaches combined with multivariate statistical and data fusion analysis,which can determine the influences of host plant and habitat on the metabolites,is a powerful strategy to control the quality of semi-parasitic herbal medicine. 展开更多
关键词 Viscum coloratum HOST ENVIRONMENT Plant metabolomics Multivariate statistical analysis Biological activity
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Discrimination of aqueous and vinegary extracts of Shixiao San using metabolomics coupled with multivariate data analysis and evaluation of antihyperlipidemic effect 被引量:1
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作者 Xiaofan Wang Xu Zhao +3 位作者 Liqiang Gu Yuanyuan Zhang Kaishun Bi Xiaohui Chen 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第1期17-26,共10页
A novel study using LCeMS(Liquid chromatography tandem mass spectrometry)coupled with multivariate data analysis and bioactivity evaluation was established for discrimination of aqueous extract and vinegar extract of... A novel study using LCeMS(Liquid chromatography tandem mass spectrometry)coupled with multivariate data analysis and bioactivity evaluation was established for discrimination of aqueous extract and vinegar extract of Shixiao San.Batches of these two kinds of samples were subjected to analysis,and the datasets of sample codes,tR-m/z pairs and ion intensities were processed with principal component analysis(PCA).The result of score plot showed a clear classification of the aqueous and vinegar groups.And the chemical markers having great contributions to the differentiation were screened out on the loading plot.The identities of the chemical markers were performed by comparing the mass fragments and retention times with those of reference compounds and/or the known compounds published in the literatures.Based on the proposed strategy,quercetin-3-Oneohesperidoside,isorhamnetin-3-O-neohespeeridoside,kaempferol-3-O-neohesperidoside,isorhamnetin-3-O-rutinoside and isorhamnetin-3-O-(2G-a-l-rhamnosyl)-rutinoside were explored as representative markers in distinguishing the vinegar extract from the aqueous extract.The anti-hyperlipidemic activities of two processed extracts of Shixiao San were examined on serum levels of lipids,lipoprotein and blood antioxidant enzymes in a rat hyperlipidemia model,and the vinegary extract,exerting strong lipid-lowering and antioxidative effects,was superior to the aqueous extract.Therefore,boiling with vinegary was predicted as the greatest processing procedure for anti-hyperlipidemic effect of Shixiao San.Furthermore,combining the changes in the metabolic profiling and bioactivity evaluation,the five representative markers may be related to the observed antihyperlipidemic effect. 展开更多
关键词 Anti-hyperlipidemic effect Herb processing Multivariate data analysis Shixiao San Liquid chromatography tandem mass spectrometry
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In-line spectroscopy combined with multivariate analysis methods for endpoint determination in column chromatographic adsorption processes for herbal medicine 被引量:3
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作者 Cheng Jiang Haibin Qu 《Acupuncture and Herbal Medicine》 2022年第4期253-260,共8页
Objective: In a chromatographic cycle, the adsorption process is a critical unit operation that has a significant impact on downstream processes and, ultimately, the quality of the final products. The development of a... Objective: In a chromatographic cycle, the adsorption process is a critical unit operation that has a significant impact on downstream processes and, ultimately, the quality of the final products. The development of a rapid method to determine the endpoints of adsorption processes in a large-scale manufacturing is of substantial importance for herbal medicine(HM) manufacturers.Methods: In this study, the adsorption of saponins on a macroporous resin column chromatograph, a critical unit operation in Panax notoginseng(Burkill) F.H.Chen injection manufacturing, was considered as an example. The evaluation results of in-line ultraviolet and visible spectra combined with various multivariate analysis methods, including the moving block standard deviation(MBSD), difference between the moving block average and the target spectrum(DMBA-TS), soft-independent modeling of class analogy(SIMCA), and partial least-squares discriminant analysis(PLS-DA), were compared.Results: MBSD was unsuitable for adsorption processes. The relative standard errors of prediction between the predicted and experimental endpoints were 13.2%, 4.67%, and 5.71% using DMBA-TS, SIMCA, and PLS-DA, respectively.Conclusions: Among the considered analysis methods, SIMCA and PLS-DA were more effective for endpoint determination. The results of this study provide a more comprehensive overview of the effectiveness of various multivariate analysis methods to facilitate the selection of the most suitable method. This study was also conducive to address the issues of the in-line detection of adsorption endpoints to guide practical HM manufacturing. 展开更多
关键词 Adsorption ENDPOINT Herbal medicine Multivariate analysis Ultraviolet and visible
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The Bio-Geographical Regions Division of Global Terrestrial Animal by Multivariate Similarity Clustering Analysis Method 被引量:3
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作者 Qi Shen Jiqi Lu +3 位作者 Shujie Zhang Zhixing You Yingdang Ren Xiaocheng Shen 《Open Journal of Ecology》 2022年第3期236-255,共20页
A novel multivariate similarity clustering analysis (MSCA) approach was used to estimate a biogeographical division scheme for the global terrestrial fauna and was compared against other widely used clustering algorit... A novel multivariate similarity clustering analysis (MSCA) approach was used to estimate a biogeographical division scheme for the global terrestrial fauna and was compared against other widely used clustering algorithms. The faunal dataset included almost all terrestrial and freshwater fauna, a total of 4631 families, 141,814 genera, and 1,334,834 species. Our findings demonstrated that suitable results were only obtained with the MSCA method, which was associated with distinct hierarchies, reasonable structuring, and furthermore, conformed to biogeographical criteria. A total of seven kingdoms and 20 sub-kingdoms were identified. We discovered that the clustering results for the higher and lower animals did not differ significantly, leading us to consider that the analysis result is convincing as the first zoogeographical division scheme for global all terrestrial animals. 展开更多
关键词 Global Animal Multivariate Similarity Clustering analysis BIOGEOGRAPHY REGIONALIZATION
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Physicochemical Properties of Banana Flour as Influenced by Variety and Stage of Ripeness: Multivariate Statistical Analysis 被引量:1
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作者 S. bin Ramli A. F. M. Alkarkhi +1 位作者 Y. S. Yong A. M. Easa 《Journal of Agricultural Science and Technology》 2010年第1期69-78,共10页
Physicochemical properties of banana flour (BF) were studied in two varieties (Cavendish and Dream) and two stages of ripeness (green and ripe). BF's were analyzed for pH, total soluble solids (TSS), water ho... Physicochemical properties of banana flour (BF) were studied in two varieties (Cavendish and Dream) and two stages of ripeness (green and ripe). BF's were analyzed for pH, total soluble solids (TSS), water holding capacity (WHC) and oil holding capacity (OHC) at 40℃, 60 ℃ and 80 ℃, color values L*, a* and b*, back extrusion force and viscosity. Physicochemical data were analyzed by Multivariate Analysis of Variance, discriminant analysis and cluster analysis. All statistical analyses showed that physicochemical properties of BF prepared from different variety and stage of ripeness were different from each other. Viscosity, WHC40, WHC60 and TSS were recommended methods for discrimination between banana flour prepared from the two varieties, whilst viscosity, WHC60 and WHC80 were suggested for differentiation of banana flour prepared using green and ripe banana. 展开更多
关键词 Physicochemical properties banana flour Multivariate analysis of Variance cluster analysis discriminant analysis.
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A New Fracability Evaluation Approach for Shale Reservoirs Based on Multivariate Analysis: A Case Study in Zhaotong Shale Gas Demonstration Zone in Sichuan, China
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作者 LIU Shanyong LI Lin +2 位作者 YUAN Yuan LOU Yishan LI Zhonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第4期1005-1014,共10页
Fracability characterizes the effectiveness of hydraulic fracturing.The existing assessment methods cannot reflect the actual value of the effectiveness due to a lack of comprehensive consideration and neglect of the ... Fracability characterizes the effectiveness of hydraulic fracturing.The existing assessment methods cannot reflect the actual value of the effectiveness due to a lack of comprehensive consideration and neglect of the influences of engineering factors.This study aims to solve this problem by implementing geological static data and production dynamic data in multivariate analysis in Zhaotong shale gas demonstration zone.First,the reservoir quality index(RQI)was introduced to evaluate the exploration potential by integrating the geological parameters with gray relational analysis.Moreover,the differences in fracturing fluid types and proppant sizes were considered,and the operating parameters were normalized on the basis of the equivalence principle.Finally,the general reservoir fracability index(GRFI)was proposed based on a dimensioned processing of the various parameters.A case study was conducted to verify the accuracy and feasibility of this new approach.The results demonstrate that(1)the organic carbon and gas content are adjusted to contribute the most to the calculation of the RQI,while the effective porosity contributes the least;(2)the fracturing scale is the main operating parameter determining the fracability,which has the strongest correlation with the effectiveness of fracking;and(3)the GRFI has a positive correlation with shale gas production,and the lower limit of the GRFI of 2,000 corresponds to a daily production of 50,000 m3/d;this value is defined as the threshold value of a stripper well.The GRFI is consistent with the productivity trend of shale gas wells in the research block,which suggests that the new model is accurate and practical for well candidate selection. 展开更多
关键词 fracability multivariate analysis equivalence principle network fracturing shale gas
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Hydrogeochemical processes and multivariate analysis for groundwater quality in the arid Maadher region of Hodna,northern Algeria
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作者 Tahar Selmane Mostefa Dougha +2 位作者 Mahmoud Hasbaia Ahmed Ferhati Ali Redjem 《Acta Geochimica》 EI CAS CSCD 2022年第5期893-909,共17页
This study focused on water quality and hydrogeochemical processes(evolution,origin)in the Maadher region,central Hodna in Algeria.In recent decades,the excessive exploitation of this resource due to urbanization,irri... This study focused on water quality and hydrogeochemical processes(evolution,origin)in the Maadher region,central Hodna in Algeria.In recent decades,the excessive exploitation of this resource due to urbanization,irrigation,and the effect of climate change reaching the countries of northern Africa have caused a decline in water levels and hydrochemical changes in the aquifer.The sampling campaign in 2019 based on 13 physicochemical parameters was carried out on the water from 32 boreholes in the study area,compared to data archives of both sampling campaigns in 1967 and 1996.The result revealed that the groundwater as a whole has moderate freshwater quality,due to its total dissolved solids(TDS)content and other dissolved ions of concern(nitrate NO),which exceed WHO standards.In addition,Piper diagram indicates that the hydrochemical facies of sulfate–chloride–nitrate–calcium(SO–Cl–NO–Catype),which globally characterizes the study area and these elements are the dominant dissolved ions.Principal component analysis and hierarchical cluster analysis(HCA)methodologies are applied in order to define the major control factors that affect the hydrochemistry of Maadher plain.Three distinct water groups were found,illustrating a different evolution of salinity(EC and TDS).The HCA indicated an interesting cluster with a distinct contamination signature and most likely with significantly higher sulfate,chloride,and nitrate concentrations.Anthropogenic processes also play an important role in the study area.The water resource comes from Bousaada Wadi,the exchange at the aquifer depth and the agricultural practices contribute to the deterioration of the quality. 展开更多
关键词 Groundwater quality Hydrogeochemical processes Multivariate analysis SALINITY Mio-Plio-Quaternary aquifer
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Multivariate analysis of the risk for pulmonary complication after gastrointestinal surgery
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作者 Shan-PingJiang Zhi-YingLi +3 位作者 Li-WenHuang WeiZhang Zhi-QiangLu Zhi-YongZheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第24期3735-3741,共7页
AIM: To identify the risk factors for postoperative pulmonary complications (PPC) after gastrointestinal surgery. METHODS: A total of 1 002 patients undergoing gastrointestinal surgery in the Second Affiliated Hospita... AIM: To identify the risk factors for postoperative pulmonary complications (PPC) after gastrointestinal surgery. METHODS: A total of 1 002 patients undergoing gastrointestinal surgery in the Second Affiliated Hospital, Sun Yat-Sen University, during December 1999 and December 2003, were retrospectively studied. RESULTS: The overall incidence of PPC was 22.8% (228/ 1 002). Multivariate logistic analysis identified nine risk factors associated with PPC, including age odds ratio (OR = 1.040) history of respiratory diseases (OR = 2.976), serum albumin (OR = 0.954), chemotherapy 2 wk before operation (OR = 3.214), volume of preoperative erythrocyte transfusion (OR = 1.002), length of preoperative antibiotic therapy (OR = 1.072), intraoperative intratracheal intubation (OR = 1.002), nasogastric intubation (OR = 1.050) and postoperative mechanical ventilation (OR = 1.878). Logistic regression equation for predicting the risk of PPC was P(1) =q/[1+e-(-3.488+0.039×+1.090×Rd+0.001×Rbc-0.0047×Alb+0.002×Lii+ 0.049×Lni+0.630×Lmv+0.070×Dat+1.168×a)]. 展开更多
关键词 Postoperative pulmonary complications Gastrointestinal surgery Multivariate analysis
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Multivariate analysis of serum surface-enhanced Raman spectroscopy of liver cancer patients
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作者 Qiwen Wang Sen Wang +3 位作者 Shengdong Cui Deyuan Yang Zheng Huang Shusen Xie 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第5期74-82,共9页
Early diagnosis of liver cancer plays a significant role in reducing its high mortality.In this preliminary study,the feasibility of using serum surface-enhanced Raman spectroscopy(SERS)to identify liver cancer was st... Early diagnosis of liver cancer plays a significant role in reducing its high mortality.In this preliminary study,the feasibility of using serum surface-enhanced Raman spectroscopy(SERS)to identify liver cancer was studied.Serum samples were obtained from liver cancer patients and healthy controls.The differences between the SERS spectra of pre-operation and postoperation of liver cancer patients were also analyzed.The general shape and trend of SERS spectra of health control and liver cancer patients were similar.Multivariate analysis,e.g.,PLSSVM,might be useful for the discrimination of serum SERS spectra of pre-operation and post-operation. 展开更多
关键词 Surface-enhanced Raman spectroscopy(SERS) SERUM liver cancer multivariate analysis
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