The multivariate statistical techniques, principal component analysis, Q-modefactor analysis, correspondence analysis and fuzzy C-means clustering were applied to analyzing thedatasets of minor element concentrations ...The multivariate statistical techniques, principal component analysis, Q-modefactor analysis, correspondence analysis and fuzzy C-means clustering were applied to analyzing thedatasets of minor element concentrations in sediment samples of a core collected from the outershelf of the East China Sea. According to the analysis results, the sediment core Q43 can be dividedinto three strata with different features in minor elements. The first stratum (unit Ⅰ) ischaracterized by higher concentrations of Ⅴ, Cr, Cd and Sc, which are active and inactive elements.The second stratum (unit Ⅱ) is controlled by ultrastable elements Ⅴ, Ti, Cr, Th, Sc, Pb, etc. Thethird stratum (unit Ⅲ) is dominated by Ni, Co, Ba, Rb and Mn, which are authigenic andvolcanogenic elements. The geochemical features of the core Q43 show environmental changes in thedepositional process from the Late Pleistocene to Holocene.展开更多
China＇s educational enterprise has achieved great successes since reform and opening up in 1978, but the constraints imposed by a number of factors mean that the problem of unequal distribution of high quality educat...China＇s educational enterprise has achieved great successes since reform and opening up in 1978, but the constraints imposed by a number of factors mean that the problem of unequal distribution of high quality educational resources among groups from different strata is becoming increasingly noticeable at the basic education stage, leading to socioeconomic segregation in schools. We utilize baseline data from the China Education Panel Survey for 2013-2014 to investigate this phenomenon in junior high schools and its influence upon students＇ educational expectations. Our findings show that marked segregation currently exists at the junior high school level. The extent of the segregation varies from region to region and place to place （urban or rural）, and school socioeconomic composition （SEC） exerts a significant influence upon students＇ educational expectations. The higher the school＇s average SEC or the greater its heterogeneity, the higher the educational expectations of its students. The effect of school SEC upon the educational expectations of students varies depending on the characteristics of different student groups; students who have lower cognitive abilities and fall behind at school are more likely to benefit from an increase in school socioeconomic status （SES） and heterogeneity. Because educational expectationsare a decisive factor in academic achievement and educational attainment, the influence of school socioeconomic segregation upon educational equity should not be overlooked. Lessening the degree of school socioeconomic segregation and encouraging integrated schools would be an effective measure for ensuring educational equity in China.展开更多
基金funded by the National Natural Science Foundation(Nos.40176014 and 40067013).
文摘The multivariate statistical techniques, principal component analysis, Q-modefactor analysis, correspondence analysis and fuzzy C-means clustering were applied to analyzing thedatasets of minor element concentrations in sediment samples of a core collected from the outershelf of the East China Sea. According to the analysis results, the sediment core Q43 can be dividedinto three strata with different features in minor elements. The first stratum (unit Ⅰ) ischaracterized by higher concentrations of Ⅴ, Cr, Cd and Sc, which are active and inactive elements.The second stratum (unit Ⅱ) is controlled by ultrastable elements Ⅴ, Ti, Cr, Th, Sc, Pb, etc. Thethird stratum (unit Ⅲ) is dominated by Ni, Co, Ba, Rb and Mn, which are authigenic andvolcanogenic elements. The geochemical features of the core Q43 show environmental changes in thedepositional process from the Late Pleistocene to Holocene.
文摘China＇s educational enterprise has achieved great successes since reform and opening up in 1978, but the constraints imposed by a number of factors mean that the problem of unequal distribution of high quality educational resources among groups from different strata is becoming increasingly noticeable at the basic education stage, leading to socioeconomic segregation in schools. We utilize baseline data from the China Education Panel Survey for 2013-2014 to investigate this phenomenon in junior high schools and its influence upon students＇ educational expectations. Our findings show that marked segregation currently exists at the junior high school level. The extent of the segregation varies from region to region and place to place （urban or rural）, and school socioeconomic composition （SEC） exerts a significant influence upon students＇ educational expectations. The higher the school＇s average SEC or the greater its heterogeneity, the higher the educational expectations of its students. The effect of school SEC upon the educational expectations of students varies depending on the characteristics of different student groups; students who have lower cognitive abilities and fall behind at school are more likely to benefit from an increase in school socioeconomic status （SES） and heterogeneity. Because educational expectationsare a decisive factor in academic achievement and educational attainment, the influence of school socioeconomic segregation upon educational equity should not be overlooked. Lessening the degree of school socioeconomic segregation and encouraging integrated schools would be an effective measure for ensuring educational equity in China.
