期刊文献+
共找到142篇文章
< 1 2 8 >
每页显示 20 50 100
陆相断陷盆地岩性油气藏形成与分布的“多元控油—主元成藏”特征 被引量:75
1
作者 刘震 赵阳 +5 位作者 杜金虎 肖伟 金博 许晓明 梁全胜 郝琦 《地质科学》 CAS CSCD 北大核心 2006年第4期612-635,共24页
陆相断陷盆地岩性油气藏的形成和分布受到多种因素的控制(包括多项宏观地质因素和微观地质因素),很难用一个统一的模式来解释,表现出显著的“差异性”特征。岩性油气藏形成并分布在沉积盆地中,它必然首先要受盆地中宏观石油地质条件的影... 陆相断陷盆地岩性油气藏的形成和分布受到多种因素的控制(包括多项宏观地质因素和微观地质因素),很难用一个统一的模式来解释,表现出显著的“差异性”特征。岩性油气藏形成并分布在沉积盆地中,它必然首先要受盆地中宏观石油地质条件的影响,如:1)构造带类型的影响,2)沉积体系域类型的控制,3)储集相类型的控制,4)烃源岩的控制以及5)盆地温—压系统的控制等。根据岩性油气藏形成的基本条件和岩性圈闭成藏控制因素的分析,认为岩性圈闭能否成藏主要受4大主控因素制约:1)油气运移通道因素,2)流体动力因素,3)储层临界物性因素,和4)砂体封闭因素。本文力图用“多元控油—主元成藏”规律来概括这一特征,以期在石油地质理论和岩性油气藏勘探方面起到促进作用。 展开更多
关键词 油气藏“多元控油-主成藏” 形成与分布特征 陆相断陷盆地
下载PDF
论德性的统一性 被引量:1
2
作者 张光华 《江汉论坛》 CSSCI 北大核心 2008年第9期41-44,共4页
德性的统一性问题是德性论者的重要话题之一。从古希腊到当代,德性论者持续对这个问题进行了探讨。苏格拉底相信只存在一种德性,单一性就是德性统一的具体形式;柏拉图和亚里士多德则认为德性的统一性表现为多种德性的联合体,即"多... 德性的统一性问题是德性论者的重要话题之一。从古希腊到当代,德性论者持续对这个问题进行了探讨。苏格拉底相信只存在一种德性,单一性就是德性统一的具体形式;柏拉图和亚里士多德则认为德性的统一性表现为多种德性的联合体,即"多元德性统一性";而荷斯特豪斯则在此基础上提出了"弱多元德性统一性"思想,丰富和发展了当代的德性理论。 展开更多
关键词 统一 单一德统一 多元统一 多元统一
下载PDF
Influence of confined water on the limit support pressure of tunnel face in weakly water-rich strata
3
作者 LI Yun-fa WU Guo-jun +2 位作者 CHEN Wei-zhong YUAN Jing-qiang HUO Meng-zhe 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2844-2859,共16页
In the process of shield tunneling through soft soil layers,the presence of confined water ahead poses a significant threat to the stability of the tunnel face.Therefore,it is crucial to consider the impact of confine... In the process of shield tunneling through soft soil layers,the presence of confined water ahead poses a significant threat to the stability of the tunnel face.Therefore,it is crucial to consider the impact of confined water on the limit support pressure of the tunnel face.This study employed the finite element method(FEM)to analyze the limit support pressure of shield tunnel face instability within a pressurized water-containing layer.Subsequently,a multiple linear regression approach was applied to derive a concise solution formula for the limit support pressure,incorporating various influencing factors.The analysis yields the following conclusions:1)The influence of confined water on the instability mode of the tunnel face in soft soil layers makes the displacement response of the strata not significant when the face is unstable;2)The limit support pressure increases approximately linearly with the pressure head,shield tunnel diameter,and tunnel burial depth.And inversely proportional to the thickness of the impermeable layer,soil cohesion and internal friction angle;3)Through an engineering case study analysis,the results align well with those obtained from traditional theoretical methods,thereby validating the rationality of the equations proposed in this paper.Furthermore,the proposed equations overcome the limitation of traditional theoretical approaches considering the influence of changes in impermeable layer thickness.It can accurately depict the dynamic variation in the required limit support pressure to maintain the stability of the tunnel face during shield tunneling,thus better reflecting engineering reality. 展开更多
关键词 weakly water-rich strata confined aquifer limit support pressure finite element method multiple linear regression
下载PDF
认同的“体”现:打造跨性别
4
作者 何春蕤(Josephine Ho) 《臺灣社會研究》
这篇论文尝试具体记录台湾某些跨性别主体如何在有限的、被排挤的社会资源和空间内积极打造自己的身体和形象,以构筑并管理她/他们的身体和认同。本文一方面显示台湾跨性别身体之社会存在的特殊性(the specificity of trans-gender ex... 这篇论文尝试具体记录台湾某些跨性别主体如何在有限的、被排挤的社会资源和空间内积极打造自己的身体和形象,以构筑并管理她/他们的身体和认同。本文一方面显示台湾跨性别身体之社会存在的特殊性(the specificity of trans-gender existence),以及这些主体在面对社会局限时所各自签展出来的动态策略,显示众多跨性别主体在性别、年龄、社经地位、外貌、体型等等方面的差异存在条件(这些条件状态都可能影响到「体现身体」时能有多少说服力);另方面也想探究跨性别主体在斡旋构筑这个社会存在时所逐渐浮现的主体性,也就是探究跨性别主体在管理身体与认同时所做的日复一日打造工程已经在社会文化中投下何种值得观察的性别变数(而这些打造工程也持续折射「性别的体现」的含意和表现)。 展开更多
关键词 體現 別認同 別二分主義 別殊異 性多元 社會建構論 變裝
全文增补中
Burner effects on melting process of regenerative aluminum melting furnace 被引量:2
5
作者 王计敏 许朋 +4 位作者 闫红杰 周孑民 李世轩 贵广臣 李文科 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3125-3136,共12页
According to the features of melting process of regenerative aluminum melting furnaces, a three-dimensional mathematical model with user-developed melting model, burner reversing and burning capacity model was establi... According to the features of melting process of regenerative aluminum melting furnaces, a three-dimensional mathematical model with user-developed melting model, burner reversing and burning capacity model was established. The numerical simulation of melting process of a regenerative aluminum melting furnace was presented using hybrid programming method of FLUENT UDF and FLUENT scheme based on the heat balance test. Burner effects on melting process of aluminum melting furnaces were investigated by taking optimization regulations into account. The change rules of melting time on influence factors are achieved. Melting time decreases with swirl number, vertical angle of burner, air preheated temperature or natural gas flow; melting time firstly decreases with horizontal angle between burners or air-fuel ratio, then increases; melting time increases with the height of burner. 展开更多
关键词 regenerative aluminum melting furnace BURNER melting process numerical simulation multi-element non-linearregression
下载PDF
Kinetics of thermal decomposition of lanthanum oxalate hydrate 被引量:11
6
作者 詹光 余军霞 +2 位作者 徐志高 周芳 池汝安 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第4期925-934,共10页
Lanthanum oxalate hydrate La2(C2O4)3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2(C2O4)3·10H2O ... Lanthanum oxalate hydrate La2(C2O4)3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2(C2O4)3·10H2O from room temperature to 900 °C was investigated and intermediates and final solid products were characterized by FTIR and DSC-TG.Results show that the thermal decomposition process consists of five consecutive stage reactions.Flynn-Wall-Ozawa(FWO) and Kissinger-Akahira-Sunose(KAS) methods were implemented for the calculation of energy of activation(E),and the results show that E depends on α,demonstrating that the decomposition reaction process of the lanthanum oxalate is of a complex kinetic mechanism.The most probable mechanistic function,G(α)=[1-(1+α)1/3]2,and the kinetic parameters were obtained by multivariate non-linear regression analysis method.The average E-value that is compatible with the kinetic model is close to value which was obtained by FWO and KAS methods.The fitting curve matches the original TG curve very well. 展开更多
关键词 lanthanum oxalate decahydrate TG-DSC thermal decomposition multivariate non-linear regression analysis
下载PDF
Finite element analysis of stress at implant-bone interface of dental implants with different structures 被引量:3
7
作者 陈良建 何浩 +3 位作者 李益民 李挺 郭小平 汪瑞芳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1602-1610,共9页
The effect of structure,elastic modulus and thickness of lower modulus layer in porous titanium implants on the stress distribution at the implant-bone interface was investigated.Three-dimensional finite element model... The effect of structure,elastic modulus and thickness of lower modulus layer in porous titanium implants on the stress distribution at the implant-bone interface was investigated.Three-dimensional finite element models of different titanium implants were constructed.The structures of the implants included the whole lower modulus style (No.1),bio-mimetic style (No.2),the whole lower modulus style in cancellous bone (No.3) and the whole dense style No.4.The stress distributions at bone-implant interface under static loading were analyzed using Ansys Workbench 10.0 software.The results indicated that the distribution of interface stress is strongly depended on the structure of the implants.The maximum stresses in cancellous bone and root region of implant No.2 are lower than those in the other three implants.A decrease in the modulus of the low modulus layer facilitates the interface stress transferring.Increasing the thickness of the low modulus layer can reduce the stress and induce a more uniform stress distribution at the interface.Among the four implants,biomimetic style implant No.2 is superior in transferring implant-bone interface stress to surrounding bones. 展开更多
关键词 titanium implant elastic modulus finite element analysis porous structure
下载PDF
Quasi-χ~2 Distribution and the Independence of Wishart Distribution
8
作者 朱道元 赵胜利 《Journal of Southeast University(English Edition)》 EI CAS 2002年第2期173-176,共4页
In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of i... In this paper, the authors generalize the definition of χ 2 distribution and introduce a quasi χ 2 distribution, and then prove several properties of it, find the necessary and sufficient conditions of independence about multivariate normal distributions, matrix normal distributions and two parts of the Wishart distribution. 展开更多
关键词 quasi χ 2 Wishart distribution INDEPENDENCE
下载PDF
Exploration of the spatial pattern of urban residential land use with geographically weighted regression technique: a case study of Nanjing,China 被引量:1
9
作者 胡明星 吴江 朱选 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期149-156,共8页
As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geo... As the traditional methods and technical means cannot meet the quantitative research needs of the urban land use patterns, quantitative research methods for the urban land use pattern are established via the GIS (geographic information system ) technique combined with the related theories and models. Taking the city of Nanjing as an example, a spatial database of urban land use and other environmental and socio-economic data is constructed. A multiple linear regression model is developed to determine the statistically significant factors affecting the residential land use distributions. To explain the spatial variations of urban land use patterns, the geographically weighted regression (GWR) is employed to establish spatial associations between these significant factors and the distribution of urban residential land use. The results demonstrate that the GWR can provide an effective approach to the exploration of the urban land use spatial patterns and also provide useful spatial information for planning residential development and other types of urban land use. 展开更多
关键词 urban residential land use GIS (geographic information system) multiple linear regression geographically weighted regression
下载PDF
Genetic diversity and differentiation of the Dybowski's frog(Rana dybowskii) in Northeast China 被引量:5
10
作者 张明 贾学渊 马建章 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期239-245,I0008,共8页
The genetic diversity and population structure of the Dybowski's frog(Rana dybowskii) were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser K... The genetic diversity and population structure of the Dybowski's frog(Rana dybowskii) were investigated by using 11 polymorphic microsatellite loci.Total 75 individuals were sampled from six populations in Lesser Khingan Mountains and Changbai Mountains,China.Results showed that allele number of the 11 microsatellite loci was in the range of 2-10 in all populations,with the mean of 5.6.The average expected heterozygosity(HE) was 0.572,indicating a moderate polymorphism.The results of genetic differentiation coefficient(FST) showed that population genetic differentiation was significant between Changbai and Lesser Khingan Mountains(p〈0.001).This result was verified further by Nei's genetic distance(DA) based on UPGMA phy-logenetic trees and by AMOVA analysis.In conclusion,the populations distributed in Lesser Khingan Mountains and Changbai Mountain are proposed to be two distinct management units(MUs) for their protection and management. 展开更多
关键词 Dybowski's frog(Rana dybowskii) genetic diversity genetic differentiation management units(MUs) MICROSATELLITE
下载PDF
Prediction of Demand and Tendency of the Book Market in China
11
作者 李海霞 孙学良 赵黎明 《Transactions of Tianjin University》 EI CAS 2002年第3期216-220,共5页
The prediction model of the demand of the book market in China from the quantitative angle is established,and the total demand of the books for years from 2002 to 2004 is predicted.The effects of the gross domestic pr... The prediction model of the demand of the book market in China from the quantitative angle is established,and the total demand of the books for years from 2002 to 2004 is predicted.The effects of the gross domestic product,household consumption,price and population on the demand of books are also analyzed.In the end,it is summarized that the acceleration of the development of Chinese book industry,the refinement of the books,the innovation of the advertisement,the series of the structure and the steady increase of the price will become the remarkable characteristics of the book market. 展开更多
关键词 book market DEMAND multiple linear regression
下载PDF
Establishment of a mdr1 Multidrug Resistant Model of Orthotopic Transplantation of Liver Carcinoma on Nude Mice 被引量:1
12
作者 韩宇 陈孝平 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期86-88,共3页
To develop a new method of inducing mdrl multidrug resistance by establishinga nude mice model of orthotopic transplantation of liver carcinoma by sporadic abdominalchemotherapy at intervals. Methods: Hepatocellular c... To develop a new method of inducing mdrl multidrug resistance by establishinga nude mice model of orthotopic transplantation of liver carcinoma by sporadic abdominalchemotherapy at intervals. Methods: Hepatocellular carcinoma HepG2 cell was cultured and injectedsubcutaneously to form the tumor-supplying mice. The tumor bits from the tumor-supplying mice wereimplanted under the envelope of the mice liver and induced by abdominal chemotherapy withPharmorubicin. Physical examination, ultrasonography, spiral CT and operative inspection were usedto examine tumor progression. RT-PCR and immunohistochemistry were adopted to detect the expressionof mdr1-mRNA and its encoded protein P-gp protein (P-gp). Results: There was no operative dead, therate of implanting tumor successfully was 88% (22/25), the rate of implanting secondly successfullywas 100% (3/3), and the rate of inducing successfully was 80% (16/20). The expression of mdrl-mRNAand the P-gp in the inducing group was 23 folds and 13 folds in the control group respectively.Conclusion: We have established an in vivo model of mdr using nude mice transplanted with orthotopicliver neoplasm coupled to chemotherapy. 展开更多
关键词 liver neoplasms GENES MDR mice nude disease models ANIMAL
下载PDF
Multivariate Analysis of Community Structure Variation of Plankton and Zoobenthos in Municipal Polluted River
13
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
下载PDF
Research on Stoichiometry of Early-spring Herbs Functional Group in the Subtropical Artificial Wetland
14
作者 牛晓音 常杰 +1 位作者 葛滢 郑家文 《Agricultural Science & Technology》 CAS 2011年第8期1182-1185,1190,共5页
[Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammoni... [Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammonium nitrogen and phosphorus concentrations.Potassium persulfate absorptiometry was used for the measurement of total N content,while the flame photometer was used to detect the potassium and sodium concentration in plants.All the nutrient determination of plant samples were repeated for four times.[Result]The four nutrient concentrations in almost all samples were in the normal range of natural plant nutrition concentrations;in early-spring herbs functional groups,different species showed diversity on the nutrient concentrations;plant height had no significant effect on the nutrient concentrations in plants;the nutrient concentrations of non-grass group plants were higher than that of grass group plants;the nutrient concentrations of the annual herb were higher than that of perennial herbs.[Conclusion]The study had provided basis for the understanding of the effects of changes in nutritional conditions on species diversity,community structure and succession of the system. 展开更多
关键词 Early-spring herbs Functional group BIODIVERSITY Element STOICHIOMETRY
下载PDF
Using ^(99m)Tc-MIBI to Evaluate the Effects of Chemosensitizer on P-glycoprotein in Multidrug-resistant Carcinoma Cells
15
作者 张振蔚 张雪梅 +4 位作者 吴华 赵明 鲜于志群 周健 赖世英 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第2期83-85,共3页
To establish a method to evaluate the effects of chemosensitizer onP-glycoprotein using ^(99m)Tc-MIBI, and observe the changes of ^(99m)Tc-MIBI uptake kinetics andP-glycoprotein levels after using verapamil in MDR hum... To establish a method to evaluate the effects of chemosensitizer onP-glycoprotein using ^(99m)Tc-MIBI, and observe the changes of ^(99m)Tc-MIBI uptake kinetics andP-glycoprotein levels after using verapamil in MDR human breast cells MCF-7/Adr. Methods: MDR breastcarcinoma cells, MCF-7/Adr, were incubated and different protocols were performed. Protocol Ⅰ: achemosensitizer, verapamil (10 μmol/L), was added into cell culture medium, while in control group,the same volume of DMEM was given. Cells were harvested after 2 h incubation with ^(99m)Tc-MIBI.Protocol Ⅱ: Verapamil (10 μmol/L) was added into cell culture medium and incubated for 20 min, 40min, 60 min, 80 min, 8 h, 24 h, 48 h and 72 h respectively. Cells were harvested after 2 hincubation with ^(99m)Tc-MIBI. The radioactivity of the cells was measured and P-glycoproteinexpression levels were determined with immunohistochemical stain. Results: Protocol Ⅰ: After 2hincubation with verapamil the cellular uptake of ^(99m)Tc-MIBI was remarkably higher than controlgroup (t=2.33, P 【 0.05), but there was no difference in P-glycoprotein expression levels betweentwo groups (P 】 0.05). Protocol Ⅱ: In verapamil group, ^(99m)Tc-MIBI uptake was increased withincubation time prolonging (F=58.2, P 【 0.05). When verapamil incubation time surpassed 8 h the^(99m)Tc-MIBI uptake negatively correlated to the P-glycoprotein expression levels (r=-0.73, P 【0.01). However, when incubation time was less than 80 min, there was no correlation between^(99m)Tc-MIBI accumulation and P-glycoprotein levels (r=0.16, P 】 0.05). Conclusion: ^(99m)Tc-MIBImay be used to evaluate the qualitative as well as quantitative change of P-glycoprotein expressionlevels induced by the chemosensitizer, verapamil. 展开更多
关键词 multidrug resistance CHEMOSENSITIZER breast tumor P-GLYCOPROTEIN ^(99m)Tc-MIBI
下载PDF
Prediction Model of Secondary Substances in Anthocyanins Synthesis of Purple Corn
16
作者 朱敏 史振声 +1 位作者 李凤海 王志斌 《Agricultural Science & Technology》 CAS 2010年第8期153-156,182,共5页
The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regre... The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regression model of anthocyanins synthesis was y=4.383 86-0.205 45x1+5.479 638x2+0.195 575x4. According to standard partial regression coefficient testing,the result indicated that polyphenols content was negatively correlated with anthocyanins and the relative influence to anthocyanins synthesis was-42.7%; flavonoid content and activity of polyphenol oxidase were positively correlated with anthocyanins of purple corn and the relative influence to anthocyanins synthesis were 71.45% and 73.32% respectively. There was no positive correlation between the activity of phenylalnine ammonialyase and anthocyanins of purple corn. The establishment of multiple linear regression model of anthocyanins synthesis was to provide theory foundation of producing anthocyanins in laboratory. 展开更多
关键词 Anthocyanins Flavonoid Multiple linear regression model Purple corn POLYPHENOLS Polyphenol oxidase Phenylalnine ammonialyase
下载PDF
Linear Factorization of λ _polynomial Over Quaternionic Field 被引量:3
17
作者 郭时光 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期12-16,共5页
A proof is given that any λ _polynome over real quaternionic sfield can be factorized into produce of some linear factors.By the way,some properties and applications of this factorization in matrix theory are given.
关键词 determine polynome main spectral sequence main value SINGULAR
下载PDF
Study on QSAR of Taxol and its Derivatives Based on Stepwise Multivariate Linear Regression Analysis 被引量:1
18
作者 刘艾林 迟翰林 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第1期21-25,共5页
Abstract Using the method of stepwise multivariate linear regression (SMLR), the quantitative structure activity relationships (QSAR) of two isomeric series of taxol and its derivatives have been studied. It was foun... Abstract Using the method of stepwise multivariate linear regression (SMLR), the quantitative structure activity relationships (QSAR) of two isomeric series of taxol and its derivatives have been studied. It was found that the molar refractivity of the C3′substituent of the C13 side chain has significant correlation with its activity. We deduce that structural changes in the C3′substituents may be critical to the anticancer function. It would be useful to the design and synthesis of taxol like compounds with improved activities. 展开更多
关键词 TAXOL Stepwise multivariate linear regression (SMLR) Molar refractivity
全文增补中
MULTIVARIATE ABSOLUTE DEGREE OF GREY INCIDENCE BASED ON DISTRIBUTION CHARACTERISTICS OF POINTS
19
作者 张可 王岩 +1 位作者 辛江慧 许叶军 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期145-151,共7页
The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence ba... The analysis result of absolute degree of grey incidence for multivariate time series is often inconsistent with the qualitative analysis. To overcome this shortage, a multivariate absolute degree of grey incidence based on distribution characteristics of points is proposed. Based on the geometric description of multivariate time se- ries, the neighborhood extrema are extracted in the different regions, and a characteristic point set is constructed. Then according to the distribution of the characteristic point set, a characteristic point sequence reflecting the ge- ometric features of multivariate time series is obtained. The incidence analysis between multivariate time series is transformed into the relational analysis between characteristic point sequences, and a grey incidence model is established. The model possesses the properties of translational invariance, transpose and rank transform invari- ance, and satisfies the grey incidence analysis axioms. Finally, two cases are studied and the results prove the ef- fectiveness of the model. 展开更多
关键词 grey system absolute degree of grey incidences multivariate time series similarity measure
下载PDF
Correlation and path analysis of morphological and weight traits in marine gastropod Glossaulax reiniana 被引量:11
20
作者 赵力强 何阳阳 +2 位作者 杨凤 聂鸿涛 闫喜武 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第4期821-827,共7页
Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wil... Using correlation and path analysis, the genetic correlation between weight traits and morphological traits was determined in the marine gastropod Glossaulax reiniana. A total of 100 G. reiniana individuals from a wild population were used. Shell width (X1), shell height (X2), umbo-callus height (X3), body width (X4), operculum length (X5), operculum width (X6), body weight (Y1) and soft-tissue weight (Y2) were measured, and the correlation coefficient matrix calculated. Morphological traits were used as independent variables and weight traits as dependent variables for path coefficient analysis. Path coefficients, correlation indices and determination coefficients were also determined. Results indicate that the correlation coefficients associated with each morphological and weight trait were all highly significant (P〈0.01). After deleting redundant independent variables, the following optimum multiple regression equations were obtained using stepwise multiple regression analysis: Y1=-29.317+0.362X2+0.349X4+ 1.190)(5 for body weight; and Y2=-17.292+0.166X1+0.171X2+0.703X5, for soft-tissue weight. Operculum height had the highest positive direct correlation with both body weight and soft-tissue weight, which was in accordance with the test results obtained from determinate coefficient analysis. The indication of high genetic correlations between weight traits and morphological traits will provide valuable information for G. reiniana breeding programs. 展开更多
关键词 Glossaulax reiniana correlation and path analysis morphological traits weight traits
下载PDF
上一页 1 2 8 下一页 到第
使用帮助 返回顶部