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Multivariate Statistical Analysis of Dominating Groundwater Mineralization and Hydrochemical Evolution in Gao,Northern Mali
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作者 Adiaratou Traore Xumei Mao +2 位作者 Alhousseyni Traore Yahaya Yakubu Aboubacar Modibo Sidibe 《Journal of Earth Science》 SCIE CAS CSCD 2024年第5期1692-1703,共12页
Population growth and expanding urbanization have caused persistent shortages and contamination of groundwater resources in Mali,Africa.The increase in groundwater salinity makes it more difficult for residents to obt... Population growth and expanding urbanization have caused persistent shortages and contamination of groundwater resources in Mali,Africa.The increase in groundwater salinity makes it more difficult for residents to obtain drinking water,it is necessary to clarify the causes and control factors of groundwater mineralization in Gao region,northern Mali.Based on the analysis of the hydrochemical composition of groundwater in 24 boreholes,Piper and Sch?eller diagrams,principal component analysis(PCA)and hierarchical cluster analysis(HCA)are used to carry out multivariate statistical analysis on the main ions.The results show that the groundwater samples are weakly alkaline,with pH values ranging from 5.83 to 8.40,and the average values of boreholes are 7.50,respectively.The average electrical conductivity(EC)value is 354.4(μS/cm),and the extreme value is between 124.0 and 1247(μS/cm).Water is usually mineralized and presents nine types of water phase.The three principal components explain 84.42%of the total variance for 13 parameters.The factor F1(58.85%),the factor F2(16.88%)and the factor F3(8.69%)present for the majority of the total data set.In addition,multivariate statistical analysis confirmed the genetic relationship among aquifers and identified three main clusters.Clustering related to groundwater mineralization(F1),clustering related to oxide reduction and iron enrichment(F2),and clustering of groundwater pollution caused by nitrate and magnesium(F3).We found that agriculture,weathering activities and dissolution of geological materials promote the mineralization of groundwater.Groundwater quality in the Gao region is becoming less and less potable because of increasing salinity. 展开更多
关键词 hydrochemical composition multivariate statistical analysis MINERALIZATION hydro-chemical evolution GAO northern Mali HYDROGEOLOGY
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Combined Use of Multivariate Statistical Analysis and Hydrochemical Analysis for Groundwater Quality Evolution: A Case Study in North Chain Plain 被引量:8
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作者 Rong Ma Jiansheng Shi +1 位作者 Jichao Liu Chunlei Gui 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期587-597,共11页
Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis(MA) and hydrochemical analysis were ... Understanding the controlling factor of groundwater quality can enhance promoting sustainable development of groundwater resources. To this end, multivariate statistical analysis(MA) and hydrochemical analysis were introduced in this work. The results indicate that the canonical discriminant function with 7 parameters was established using the discriminant analysis(DA) method, which can afford 100% correct assignation according to the 3 different clusters(good water(GW), poor water(PW), and very poor water(VPW)) obtained from cluster analysis(CA). According to factor analysis(FA), 8 factors were extracted from 25 hydrochemical elements and account for 80.897% of the total data variance, suggesting that groundwater with higher concentrations of sodium, calcium, magnesium, chloride, and sulfate in southeastern study area are mainly affected by the natural process; the higher level of arsenic and chromium in groundwater extracted from northwestern part of study area are derived by industrial activities; domestic and agriculture sewage have important contribution to copper, iron, iodine, and phosphate in the northern study area. Therefore, this work can help identify the main controlling factor of groundwater quality in North China plain so as to make better and more informed decisions about how to achieve groundwater resources sustainable development. 展开更多
关键词 FACTOR groundwater quality hydrochemical variable industrial activity multivariate statistical analysis.
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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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Multivariate Statistical Process Monitoring of an Industrial Polypropylene Catalyzer Reactor with Component Analysis and Kernel Density Estimation 被引量:16
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作者 熊丽 梁军 钱积新 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期524-532,共9页
Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the t... Abstract Data-driven tools, such as principal component analysis (PCA) and independent component analysis (ICA) have been applied to different benchmarks as process monitoring methods. The difference between the two methods is that the components of PCA are still dependent while ICA has no orthogonality constraint and its latentvariables are independent. Process monitoring with PCA often supposes that process data or principal components is Gaussian distribution. However, this kind of constraint cannot be satisfied by several practical processes. To ex-tend the use of PCA, a nonparametric method is added to PCA to overcome the difficulty, and kernel density estimation (KDE) is rather a good choice. Though ICA is based on non-Gaussian distribution intormation, .KDE can help in the close monitoring of the data. Methods, such as PCA, ICA, PCA.with .KDE(KPCA), and ICA with KDE,(KICA), are demonstrated and. compared by applying them to a practical industnal Spheripol craft polypropylene catalyzer reactor instead of a laboratory emulator. 展开更多
关键词 multivariate statistical process monitoring principal comPonent analysis kermel density estimation POLYPROPYLENE catalyzer reactor fault detection data-driven tools
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Determining the spatial distribution of soil properties using the environmental covariates and multivariate statistical analysis: a case study in semi-arid regions of Iran 被引量:5
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作者 Mojtaba ZERAATPISHEH Shamsollah AYOUBI +1 位作者 Magboul SULIEMAN JesusRODRIGO-COMINO 《Journal of Arid Land》 SCIE CSCD 2019年第4期551-566,共16页
Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most re... Natural soil-forming factors such as landforms, parent materials or biota lead to high variability in soil properties. However, there is not enough research quantifying which environmental factor(s) can be the most relevant to predicting soil properties at the catchment scale in semi-arid areas. Thus, this research aims to investigate the ability of multivariate statistical analyses to distinguish which soil properties follow a clear spatial pattern conditioned by specific environmental characteristics in a semi-arid region of Iran. To achieve this goal, we digitized parent materials and landforms by recent orthophotography. Also, we extracted ten topographical attributes and five remote sensing variables from a digital elevation model(DEM) and the Landsat Enhanced Thematic Mapper(ETM), respectively. These factors were contrasted for 334 soil samples(depth of 0–30 cm). Cluster analysis and soil maps reveal that Cluster 1 comprises of limestones, massive limestones and mixed deposits of conglomerates with low soil organic carbon(SOC) and clay contents, and Cluster 2 is composed of soils that originated from quaternary and early quaternary parent materials such as terraces, alluvial fans, lake deposits, and marls or conglomerates that register the highest SOC content and the lowest sand and silt contents. Further, it is confirmed that soils with the highest SOC and clay contents are located in wetlands, lagoons, alluvial fans and piedmonts, while soils with the lowest SOC and clay contents are located in dissected alluvial fans, eroded hills, rock outcrops and steep hills. The results of principal component analysis using the remote sensing data and topographical attributes identify five main components, which explain 73.3% of the total variability of soil properties. Environmental factors such as hillslope morphology and all of the remote sensing variables can largely explain SOC variability, but no significant correlation is found for soil texture and calcium carbonate equivalent contents. Therefore, we conclude that SOC can be considered as the best-predicted soil property in semi-arid regions. 展开更多
关键词 soil properties remote sensing data topographical attributes multivariate statistical analyses GEOGRAPHIC information systems land management
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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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Experimental and Statistical Analysis of Fatigue Behavior in Zr-based Bulk Metallic Glass
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作者 Yao Zhifeng Qiao Jichao +1 位作者 Pelletier Jean-Marc Yao Yao 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2024年第11期3010-3016,共7页
Three-point bending fatigue experiments were conducted on a typical Zr-based bulk metallic glass(BMG)at ambient temperature to investigate the fatigue behavior under cyclic loading conditions.Results show that the str... Three-point bending fatigue experiments were conducted on a typical Zr-based bulk metallic glass(BMG)at ambient temperature to investigate the fatigue behavior under cyclic loading conditions.Results show that the stress amplitude-cycles to failure(S-N)curve of the Zr-based BMG is determined,and the fatigue endurance limit is 442 MPa(stress amplitude).To evaluate the probability-stress amplitude-cycles to failure(P-S-N)curve,an estimation method based on maximum likelihood was proposed,which relies on statistical principles to estimate the fatigue life of the material and allows for a reduction in the number of samples required,offering a cost-effective and efficient alternative to traditional testing methods.The experimental results align with the American Society for Testing and Materials(ASTM)standard,indicating the reliability and accuracy of this estimation method in evaluating the fatigue behavior of Zr-based BMG. 展开更多
关键词 bulk metallic glass P-S-N curve fatigue test statistical analysis
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Spatial variation assessment of groundwater quality using multivariate statistical analysis(Case Study:Fasa Plain,Iran) 被引量:3
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作者 Mehdi Bahrami Elmira Khaksar Elahe Khaksar 《Journal of Groundwater Science and Engineering》 2020年第3期230-243,共14页
Groundwater is considered as one of the most important sources for water supply in Iran.The Fasa Plain in Fars Province,Southern Iran is one of the major areas of wheat production using groundwater for irrigation.A la... Groundwater is considered as one of the most important sources for water supply in Iran.The Fasa Plain in Fars Province,Southern Iran is one of the major areas of wheat production using groundwater for irrigation.A large population also uses local groundwater for drinking purposes.Therefore,in this study,this plain was selected to assess the spatial variability of groundwater quality and also to identify main parameters affecting the water quality using multivariate statistical techniques such as Cluster Analysis(CA),Discriminant Analysis(DA),and Principal Component Analysis(PCA).Water quality data was monitored at 22 different wells,for five years(2009-2014)with 10 water quality parameters.By using cluster analysis,the sampling wells were grouped into two clusters with distinct water qualities at different locations.The Lasso Discriminant Analysis(LDA)technique was used to assess the spatial variability of water quality.Based on the results,all of the variables except sodium absorption ratio(SAR)are effective in the LDA model with all variables affording 92.80%correct assignation to discriminate between the clusters from the primary 10 variables.Principal component(PC)analysis and factor analysis reduced the complex data matrix into two main components,accounting for more than 95.93%of the total variance.The first PC contained the parameters of TH,Ca2+,and Mg2+.Therefore,the first dominant factor was hardness.In the second PC,Cl-,SAR,and Na+were the dominant parameters,which may indicate salinity.The originally acquired factors illustrate natural(existence of geological formations)and anthropogenic(improper disposal of domestic and agricultural wastes)factors which affect the groundwater quality. 展开更多
关键词 GROUNDWATER Iran multivariate statistical methods POLLUTION
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Enhancing Clothing Fit for Asian Women through Digital Transformation and Statistical Analysis
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作者 Saudia Haque Oishe Zheng Liu 《Open Journal of Applied Sciences》 2024年第11期3004-3015,共12页
This study focuses on designing a solution to the perennial issue of clothing fit in Fashion Industry using tools offered by digital technology and statistical analysis, in particular, the data gathered on Asian women... This study focuses on designing a solution to the perennial issue of clothing fit in Fashion Industry using tools offered by digital technology and statistical analysis, in particular, the data gathered on Asian women (Bangladeshi and Chinese). The study reveals that managing information can significantly enhance the capability of the industry to cater to the needs of its consumers and increase diversity. It centers on the effectiveness of turning dressmaking patterns into digital ones, thus transecting from traditional cutting and stitching to remote techniques. This entails the requirement to have correct self-measures and probable errors, which can arise in the process. Thus, with the help of regression analysis, the study identifies, which measurements are incorrect and influence the fit of the clothes, and, therefore, digital pattern creation is more accurate. Altogether, it can be observed how digitalization and statistical methods are crucial to transforming the way clothes are created to approach an ideal standard of measurements that fulfill every customer’s needs to make operational and efficient the clothing sector. 展开更多
关键词 Digital Pattern Creation statistical analysis Clothing Fit Garment Customization Apparel Industry Innovation
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Customized Optimization for Vehicle Acoustic Statistical Energy Analysis
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作者 Huang Yi Feng Qiuhan +3 位作者 Liu Jingqi Li Xueliang Liu Lin Yang Shaobo 《汽车文摘》 2024年第11期1-10,共10页
Statistical Energy Analysis(SEA) is one of the conventional tools for predicting vehicle high-frequency acoustic responses.This study proposes a new method that can provide customized optimization solutions to meet NV... Statistical Energy Analysis(SEA) is one of the conventional tools for predicting vehicle high-frequency acoustic responses.This study proposes a new method that can provide customized optimization solutions to meet NVH targets based on the specific needs of different project teams during the initial project stages.This approach innovatively integrates dynamic optimization,Radial Basis Function(RBF),and Fuzzy Design Variables Genetic Algorithm(FDVGA) into the optimization process of Statistical Energy Analysis(SEA),and also takes vehicle sheet metal into account in the optimization of sound packages.In the implementation process,a correlation model is established through Python scripts to link material density with acoustic parameters,weight,and cost.By combining Optimus and VaOne software,an optimization design workflow is constructed and the optimization design process is successfully executed.Under various constraints related to acoustic performance,weight and cost,a globally optimal design is achieved.This technology has been effectively applied in the field of Battery Electric Vehicle(BEV). 展开更多
关键词 statistical Energy analysis(SEA) Dynamic optimization Radial Basis Function(RBF) Vehicle sheet metal Sound package Battery Electric Vehicle(BEV)
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Resonance analysis of^(159)Tb(n,γ)reaction based on the CSNS Back-n experiment 被引量:1
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作者 De-Xin Wang Su-Ya-La-Tu Zhang +14 位作者 Wei Jiang Jie Ren Mei-Rong Huang Jing-Yu Tang Xi-Chao Ruan Hong-Wei Wang Long-Xiang Liu Xue Li Dan-Dan Niu Guo Li Gu-Fu Meng Yong-Shun Huang Zhi-Long Wang Yu Bai Xue Yang 《Nuclear Science and Techniques》 2025年第3期85-94,共10页
The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were... The neutron capture resonance parameters for 159Tb are crucial for validating nuclear models,nucleosynthesis during the neutron capture process,and nuclear technology applications.In this study,resonance analyses were performed for the neutron capture cross sections of 159Tb measured at the China Spallation Neutron Source(CSNS)backscattering white neutron beamline(Back-n)facility.The resonance parameters were extracted from the R-Matrix code SAMMY and fitted to the experimental capture yield up to the 1.2 keV resolved resonance region(RRR).The average resonance parameters were determined by performing statistical analysis on the set of the resonance parameters in the RRR.These results were used to fit the measured average capture cross sections using the FITACS code in the unresolved resonance region from 2 keV to 1 MeV.The contributions of partial waves l=0,1,2 to the average capture cross sections are reported. 展开更多
关键词 statistical analysis Resonance parameters ^(159)Tb(n γ)cross section γ
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Quality assessment of Jinhongtang Granule using UFLC-MS/MS and multivariate statistical analysis
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作者 Fan Wu Yu Zhang +5 位作者 Yanling Qiao Ting Zhao Baojing Zhang Bangjiang Fang Xiaokui Huo Xiaochi Ma 《Asian Journal of Traditional Medicines》 CAS 2021年第4期191-202,共12页
Jinhongtang is a traditional Chinese medicine formula composed of Rheum palmatum L.stem,Sargentodoxa cuneata stem,and Taraxacum mongolicum and is used for the treatment of sepsis.However,quality assessment method for ... Jinhongtang is a traditional Chinese medicine formula composed of Rheum palmatum L.stem,Sargentodoxa cuneata stem,and Taraxacum mongolicum and is used for the treatment of sepsis.However,quality assessment method for Jinhongtang is not available.In present study,we developed a UFLC-MS/MS method to determine 16 analytes in 20 batches of home-made and commercial Jinhongtang.Multivariate statistical analysis revealed the significant differences in the quality of home-made and commercial Jinhongtang and the difference in the quality of home-made samples was more significant.The integrated strategy based on UFLC-MS/MS and multivariate statistical analysis provided a new basis for the overall quality assessment of Jinhongtang. 展开更多
关键词 Jinhongtang quality assessment UFLC-MS/MS multivariate statistical analysis
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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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Study on the Relationship between Soil and Environment Based on Multivariate Statistical Analysis
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作者 DONG Li-li 《Meteorological and Environmental Research》 2012年第5期1-3,8,共4页
[Objective] The study aimed to study the relationship between soil and environment on the basis of multivariate statistical analysis. [ Method] Through field investigation, sampling and laboratory analysis, we discuss... [Objective] The study aimed to study the relationship between soil and environment on the basis of multivariate statistical analysis. [ Method] Through field investigation, sampling and laboratory analysis, we discussed the relationship between soil properties and environmental factors in Mizhi County, North Shaanxi by using Canoco multivariate statistical analysis. [ Result]According to the effects of various environmental factors on soil properties, the influencing order of environmental factors was land use way 〉 vegetation type 〉 vegetation restoration years 〉 vegeta- tion coverage 〉 slope aspect 〉 gradient 〉 elevation. In a word, soil properties were significantly affected by land use way and vegetation type which were the most important environmental factors of soil properties in spatial variation, while vegetation restoration years were closely related to the ac- cumulation of soil nutrients. [ Condusion]The research could provide theoretical references for the construction of ecological environment in Loess Plateau of China. 展开更多
关键词 Soil properties multivariate statistical analysis Land use Vegetation types China
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Multivariate Statistical Analysis of Large Datasets: Single Particle Electron Microscopy
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作者 Marin van Heel Rodrigo V. Portugal Michael Schatz 《Open Journal of Statistics》 2016年第4期701-739,共39页
Biology is a challenging and complicated mess. Understanding this challenging complexity is the realm of the biological sciences: Trying to make sense of the massive, messy data in terms of discovering patterns and re... Biology is a challenging and complicated mess. Understanding this challenging complexity is the realm of the biological sciences: Trying to make sense of the massive, messy data in terms of discovering patterns and revealing its underlying general rules. Among the most powerful mathematical tools for organizing and helping to structure complex, heterogeneous and noisy data are the tools provided by multivariate statistical analysis (MSA) approaches. These eigenvector/eigenvalue data-compression approaches were first introduced to electron microscopy (EM) in 1980 to help sort out different views of macromolecules in a micrograph. After 35 years of continuous use and developments, new MSA applications are still being proposed regularly. The speed of computing has increased dramatically in the decades since their first use in electron microscopy. However, we have also seen a possibly even more rapid increase in the size and complexity of the EM data sets to be studied. MSA computations had thus become a very serious bottleneck limiting its general use. The parallelization of our programs—speeding up the process by orders of magnitude—has opened whole new avenues of research. The speed of the automatic classification in the compressed eigenvector space had also become a bottleneck which needed to be removed. In this paper we explain the basic principles of multivariate statistical eigenvector-eigenvalue data compression;we provide practical tips and application examples for those working in structural biology, and we provide the more experienced researcher in this and other fields with the formulas associated with these powerful MSA approaches. 展开更多
关键词 Single Particle Cryo-EM multivariate statistical analysis Unsupervised Classification Modulation Distance Manifold Separation
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The Study of Processes Affecting Groundwater Hydrochemistry by Multivariate Statistical Analysis (Case Study: Coastal Aquifer of Ghaemshahr, NE-Iran)
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作者 Homayoun Moghimi 《Open Journal of Geology》 2017年第6期830-846,共17页
To assess the quality of groundwater resources, samples were collected from 22 points for mean annual water years of 2003 and 2015 (mean minimum and maximum water table), and 19 parameters were examined and calculated... To assess the quality of groundwater resources, samples were collected from 22 points for mean annual water years of 2003 and 2015 (mean minimum and maximum water table), and 19 parameters were examined and calculated. One of the objectives of this study was to evaluate the groundwater quality of the Ghaemshahr plain which includes the study of spatial and temporal changes of groundwater quality in different sectors and factors affecting it. In this study, combining statistical methods such as Pearson correlation coefficient, factor analysis, principal component analysis, and combined diagrams with hydrochemical methods are used to assess the chemical quality of groundwater. Samples were categorized by using cluster method and then the same samples were identified. Accordingly, samples were classified in four categories which represent the quality of groundwater in different districts. Factor analysis was used to identify the factors affecting the geochemical processes of the aquifer. Statistical methods showed that they can be used to complete the conventional methods in hydro-geochemistry as well as very precise results can be achieved. Based on the obtained results, saturation index of Ghaemshahr groundwater was super-saturated;and groundwater quality control of Ghaemshahr plain is hold by processes such as dissolution of halide (salt water intrusion of Caspian Sea and brackish fossil aquifers), calcite and dolomite (dissolution of limestone, dolomite, and marl in height), weathering sodium-rich plagioclases (clay minerals), and ion exchange. 展开更多
关键词 Caspian Sea multivariate analysis Principal Component analysis (PCA) Factor analysis (FA)
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Structure Sorting of Multiple Macromolecular States in Heterogeneous Cryo-EM Samples by 3D Multivariate Statistical Analysis
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作者 Bruno P. Klaholz 《Open Journal of Statistics》 2015年第7期820-836,共17页
Heterogeneity of biological samples is usually considered a major obstacle for three-dimensional (3D) structure determination of macromolecular complexes. Heterogeneity may occur at the level of composition or conform... Heterogeneity of biological samples is usually considered a major obstacle for three-dimensional (3D) structure determination of macromolecular complexes. Heterogeneity may occur at the level of composition or conformational variability of complexes and affects most 3D structure determination methods that rely on signal averaging. Here, an approach is described that allows sorting structural states based on a 3D statistical approach, the 3D sampling and classification (3D-SC) of 3D structures derived from single particles imaged by cryo electron microscopy (cryo-EM). The method is based on jackknifing & bootstrapping of 3D sub-ensembles and 3D multivariate statistical analysis followed by 3D classification. The robustness of the statistical sorting procedure is corroborated using model data from an RNA polymerase structure and experimental data from a ribosome complex. It allows resolving multiple states within heterogeneous complexes that thus become amendable for a structural analysis despite of their highly flexible nature. The method has important implications for high-resolution structural studies and allows describing structure ensembles to provide insights into the dynamics of multi-component macromolecular assemblies. 展开更多
关键词 Heterogeneity Structural Biology Cryo Electron Microscopy Particle SORTING MULTIPLE States Macromolecular Complexes RESAMPLING Jackknifing BOOTSTRAPPING multivariate statistical analysis 3D MSA 3D-SC RIBOSOME RNA Polymerase
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An Empirical Analysis of Factors Influencing the Tourism Economy in Henan Province
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作者 Pingping WANG Liang ZHAO 《Asian Agricultural Research》 2025年第11期25-28,共4页
[Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model... [Objectives]To study the factors influencing the tourism economy in Henan Province.[Methods]Using tourism-related data from Henan Province covering the period from 2000 to 2020,this study constructs a regression model based on multivariate statistical methods to investigate the determinants of the tourism economy.The dependent variable in the model is the domestic tourism revenue of Henan Province,while the independent variables comprise the number of tourist arrivals,total operational railway mileage,the number of travel agencies,and the per capita disposable income of urban residents.[Results]Both the total railway mileage and the per capita disposable income of urban residents are the primary factors influencing the development of Henan's tourism economy.[Conclusions]It is recommended to reduce uncertainty and liquidity constraints to mitigate residents'precautionary savings behavior,actively expand domestic demand to leverage tourism as an economic driver,and improve infrastructure to support tourism development. 展开更多
关键词 HENAN PROVINCE TOURISM ECONOMY Influencing factors multivariate statistical analysis
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Dynamic Process Monitoring Based on Dot Product Feature Analysis for Thermal Power Plants
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作者 Xin Ma Tao Chen Youqing Wang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期563-574,共12页
Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems,such as thermal power plants being studied in this work.Industrial processes are inherently d... Data-driven process monitoring is an effective approach to assure safe operation of modern manufacturing and energy systems,such as thermal power plants being studied in this work.Industrial processes are inherently dynamic and need to be monitored using dynamic algorithms.Mainstream dynamic algorithms rely on concatenating current measurement with past data.This work proposes a new,alternative dynamic process monitoring algorithm,using dot product feature analysis(DPFA).DPFA computes the dot product of consecutive samples,thus naturally capturing the process dynamics through temporal correlation.At the same time,DPFA's online computational complexity is lower than not just existing dynamic algorithms,but also classical static algorithms(e.g.,principal component analysis and slow feature analysis).The detectability of the new algorithm is analyzed for three types of faults typically seen in process systems:sensor bias,process fault and gain change fault.Through experiments with a numerical example and real data from a thermal power plant,the DPFA algorithm is shown to be superior to the state-of-the-art methods,in terms of better monitoring performance(fault detection rate and false alarm rate)and lower computational complexity. 展开更多
关键词 Computational complexity dot product feature analysis(DPFA) dynamic process multivariate statistics process monitoring
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Analysis of the effect of geology, soil properties, and land use on groundwater quality using multivariate statistical and GIS methods
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作者 Jin-Soo Lee Kyung-Seok Ko +3 位作者 Tong-Kwon Kim Jae Gon Kim Seong-Hyun Cho In-Suk Oh 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期152-152,共1页
关键词 地下水 GIS 土壤性质 地质 水质 多元统计
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