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multivariate analysis for ordination and comparison of size of Artemia cysts

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Acta Oceanologica Sinica 1998年第4期17卷 537-544页

作者： Tang Senming (Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China

It is known that the biometrics of brine shrimp cysts is of strain inherent. The analysis and comparison of the cyst charcters for the identification of unknown cysts from different geqraphical origin become mpible. In this paper, multivallate methods, mainly Principle Component analysis (PCA) and Nonmetric Multi-dimensional Scaling (MDS), are used for the purpose. od results are gained with the analysis of the published data and some row data from cyst sizes. It shows that multivariate methods can cluster the similar characteristics of batch cysts and make out impure or mingled cysts of different origin. Amng others, MDS, with row data from the cyst measurement, can be easily used for the analysis of cyst ordination and comparison. The result demonstrates that the cysts of Chinese parthenopnetic brine shrimp are well discriminated by their geographic locations along the coastal China with larger size disttibuting in the south.

关键词： Artemia,cyst biometrics multivariate analysis

multivariate analysis of subjective evaluation of indoor lighting environment

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Frontiers of Architectural Research 2021年第3期10卷 614-624页

作者： Jingyun Shen Zhiwei Lian School of Design Shanghai Jiao Tong UniversityShanghai 200240China China Institute of Urban Governance Shanghai Jiao Tong UniversityShanghai 200030China

Though subjective feelings affected by lighting have been studied a lot,multivariate experimental studies are lacking in this research *** composite rotatable design(CCRD)was applied to investigate the influence of illuminance,correlated color temperature(CCT)and illuminance uniformity on satisfaction in this study.A series of subject experiments were carried out and polynomial regression models of luminous satisfaction for different activity scenarios were *** and CCT affected the satisfaction significantly in visual task scenarios,and the effect of them was independent with each other,which was demonstrated by the regression model(R2=0.89).The variation of luminous satisfaction in general activity scenarios cannot be fully explained by the three investigated *** results contributed to the knowledge of multivariate analysis of luminous environment and indicated that much could be expected referring to the application of CCRD in this field.

关键词： Lighting satisfaction multivariate analysis Illuminance CCT Uniformity Central composite rotatable design City

Hydrogeochemical processes and multivariate analysis for groundwater quality in the arid Maadher region of Hodna,northern Algeria

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Acta Geochimica 2022年第5期41卷 893-909页

作者： Tahar Selmane Mostefa Dougha Mahmoud Hasbaia Ahmed Ferhati Ali Redjem VESDD Laboratory University of M’sila28000 M’silaAlgeria

This study focused on water quality and hydrogeochemical processes(evolution,origin)in the Maadher region,central Hodna 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 *** 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 *** 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 *** 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 *** component analysis and hierarchical cluster analysis(HCA)methodologies are applied in order to define the major control factors that affect the hydrochemistry of Maadher *** 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 *** processes also play an important role in the study *** water resource comes from Bousaada Wadi,the exchange at the aquifer depth and the agricultural practices contribute to the deterioration of the quality.

关键词： Groundwater quality Hydrogeochemical processes multivariate analysis Salinity Mio-Plio-Quaternary aquifer

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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Acta Geologica Sinica(English Edition) 2019年第4期93卷 1005-1014页

作者： LIU Shanyong LI Lin YUAN Yuan LOU Yishan LI Zhonghui Institute of Mud Logging Technology and Engineering Yangtze UniversityJingzhou 434023HubeiChina Shandong Provincial Key Laboratory of Depositional Mineralization&Sedimentary Mineral Shandong University of Science and TechnologyQingdao 266590China The Key Laboratory of Well Stability and Fluid&Rock Mechanics in Oil and Gas Reservoir of Shaanxi Province Xi’an Shiyou UniversityXi’an 710065China Research Institute of Petroleum Exploration and Development Petro ChinaZhejiang Oilfield CompanyHangzhou 310023ZhejiangChina College of Technology&Engineering Yangtze UniversityJingzhou 434020HubeiChina School of Petroleum Engineering Yangtze UniversityWuhan 430100HubeiChina

Fracability characterizes the effectiveness of hydraulic *** 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 *** study aims to solve this problem by implementing geological static data and production dynamic data in multivariate analysis in Zhaotong shale gas demonstration ***,the reservoir quality index(RQI)was introduced to evaluate the exploration potential by integrating the geological parameters with gray relational ***,the differences in fracturing fluid types and proppant sizes were considered,and the operating parameters were normalized on the basis of the equivalence ***,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 *** 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 *** 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.

关键词： fracability multivariate analysis equivalence principle network fracturing shale gas

ASSESSMENT OF LOCAL INFLUENCE IN multivariate analysis

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Acta Mathematica Scientia 1996年第3期16卷 257-264,165+266-270页

作者：石磊王学仁 Institute of Applied Mathematics of Yunnan Province Department of Statistics Yunnan University Kunming 650091 China

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.

关键词： multivariate analysis normal curvature perturbation scheme local influence

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

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Acta Geochimica 2019年第6期38卷 796-814页

作者： Oualid Bouteraa Azeddine Mebarki Foued Bouaicha Zeineddine Nouaceur Benoit Laignel Laboratory of Geology and Environment(LGE) Uni versite Freres Mentouri Constantine 1ConstantineAlgeria Department of Natural and Life Sciences Mohamed Boudiaf UniversityM'silaAlgeria LASTERNE Laboratory Universite Freres Mentouri Constantine 1ConstantineAlgeria UMR IDEES CNRS 6226 Universite de Rouen1 Rue Thomas Becket76821 Saint Aignan CedexFrance UMR CNRS 6143 M2C Department of GeologyUniversity of Rouen1 Rue Thomas Becket76821 Saint Aignan CedexFrance

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 *** analysis identified three main water types based on the major ion contents,where mineralization increased from group 1 to group *** 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 *** chemistry has a strong spatial structure for Mg,Na,Cl,and NO3,and a moderate spatial structure for EC,Ca,K,HCO3,and *** quality maps generated using ordinary Kriging are consistent with the HCA and PCA *** 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.

关键词： Groundwater multivariate analysis Geostatistical modeling Geochemical modeling Mineralization Ordinary Kriging

Subnanometer-resolved chemical imaging via multivariate analysis of tip-enhanced Raman maps

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Light(Science & Applications) 2017年第1期6卷 382-389页

作者： Song Jiang Xianbiao Zhang Yao Zhang Chunrui Hu Rui Zhang Yang Zhang Yuan Liao Zachary J Smith Zhenchao Dong JG Hou Hefei National Laboratory for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information&Quantum Physics University of Science and Technology of ChinaHefeiAnhui 230026China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefeiAnhui 230026China

Tip-enhanced Raman spectroscopy(TERS)is a powerful surface analysis technique that can provide subnanometer-resolved images of nanostructures with site-specific chemical ***,due to the limitation of weak Raman signals and the resultant difficulty in achieving TERS imaging with good signal-to-noise ratios(SNRs),the conventional single-peak analysis is unsuitable for distinguishing complex molecular architectures at the subnanometer *** we demonstrate that the combination of subnanometer-resolved TERS imaging and advanced multivariate analysis can provide an unbiased panoramic view of the chemical identity and spatial distribution of different molecules on surfaces,yielding high-quality chemical images despite limited SNRs in individual pixel-level *** methodology allows us to exploit the full power of TERS imaging and unambiguously distinguish between adjacent molecules with a resolution of~0.4 nm,as well as to resolve submolecular features and the differences in molecular adsorption *** results provide a promising methodology that promotes TERS imaging as a routine analytical technique for the analysis of complex nanostructures on surfaces.

关键词： chemical imaging hyperspectral imaging multivariate analysis nanoimaging tip-enhanced Raman spectroscopy

multivariate analysis of serum surface-enhanced Raman spectroscopy of liver cancer patients

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Journal of Innovative Optical Health Sciences 2022年第5期15卷 74-82页

作者： Qiwen Wang Sen Wang Shengdong Cui Deyuan Yang Zheng Huang Shusen Xie MOE Key Laboratory of Optoelectronic Science and Technology for Medicine and Fujian Provincial Key Laboratory for Photonics Technology Fujian Normal University Fuzhou Fujian 350007P.R.China

Early diagnosis of liver cancer plays a significant role in reducing its high *** this preliminary study,the feasibility of using serum surface-enhanced Raman spectroscopy(SERS)to identify liver cancer was *** samples were obtained from liver cancer patients and healthy *** differences between the SERS spectra of pre-operation and postoperation of liver cancer patients were also *** general shape and trend of SERS spectra of health control and liver cancer patients were *** analysis,e.g.,PLSSVM,might be useful for the discrimination of serum SERS spectra of pre-operation and post-operation.

关键词： Surface-enhanced Raman spectroscopy(SERS) serum liver cancer multivariate analysis

multivariate analysis by Cox Proportional Hazards Model on pro gnoses of patients with bile duct carcinoma after resection

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Chinese Medical Journal 2002年第10期115卷 1538-1541页

作者：何平石景森陈武科王作仁西安交通大学第一医院肝胆外科研究室西安710061

OBJECTIVE: To evaluate the influence of various clinicopathologic factors on the survival of patients with bile duct carcinoma after curative resection. METHODS: A retrospective analysis was performed on 86 cases of bile duct carcinoma treated from January 1981 to September 1995. Fifteen clinicopathologic factors that could possibly influence survival were selected. A multivariate analysis of these individuals was performed using the Cox Proportional Hazards Model. RESULTS: The overall cumulative survival rate was 73% for 1 year, 32% for 3 years and 19% for 5 years. The results of univariate analysis showed that the major significant prognostic factors for influencing survival of these patients were type of histological lesion, lymph node metastasis, pancreatic invasion, duodenal invasion, perineural invasion, macroscopic vessel involvement, resected surgical margin and depth of cancer invasion (P

关键词： Proportional Hazards Models Adult Aged Bile Duct Neoplasms Female Humans Lymphatic Metastasis Male Middle Aged multivariate analysis Neoplasm Invasiveness Prognosis Survival Rate