Key somatic variables associated with,and differences between the 4 swimming strokes

ABSTRACT

This study identified key somatic and demographic characteristics that benefit all swimmers and, at the same time, identified further characteristics that benefit only specific swimming strokes. Three hundred sixty-three competitive-level swimmers (male [n = 202]; female [n = 161]) participated in the study. We adopted a multiplicative, allometric regression model to identify the key characteristics associated with 100 m swimming speeds (controlling for age). The model was refined using backward elimination. Characteristics that benefited some but not all strokes were identified by introducing stroke-by-predictor variable interactions. The regression analysis revealed 7 “common” characteristics that benefited all swimmers suggesting that all swimmers benefit from having less body fat, broad shoulders and hips, a greater arm span (but shorter lower arms) and greater forearm girths with smaller relaxed arm girths. The 4 stroke-specific characteristics reveal that backstroke swimmers benefit from longer backs, a finding that can be likened to boats with longer hulls also travel faster through the water. Other stroke-by-predictor variable interactions (taken together) identified that butterfly swimmers are characterized by greater muscularity in the lower legs. These results highlight the importance of considering somatic and demographic characteristics of young swimmers for talent identification purposes (i.e., to ensure that swimmers realize their most appropriate strokes).     

2CUL Slavic: The View So Far

In fall 2016, the Columbia-Cornell collaboration in the area of Slavic & East European resource coordination and sharing celebrated its sixth year. The author reviews particulars of the development, implementation, and function of this program as well as some of the challenges that face such cross-institutional efforts.     

广义马氏过程及其熵率

讨论了k步广义马氏过程及其时间不变性和平稳性，给出了熵率的两种定义，说明了其等价性，还给出了平稳的广义马氏链熵率的计算公式．     

多媒体环境下大学英语教学模式探究

文章通过对现有大学英语教学模式的思考,结合外语教学特点,从多媒体视角探究了多元化英语教学模式(即立体信息输入式、自我驱动模式、电子交互模式、文化意识培养模式),以期为大学英语教学实践提供新的思路和视角。     

两指标宽过去马氏性的等价形式

证明了两指标宽过去马氏性各种形式的等价性。     

Explaining the substantial inter-domain and over-time correlations in student achievement: the importance of stable student attributes

Multi-domain and longitudinal studies of student achievement routinely find moderate to strong correlations across achievement domains and even stronger within-domain correlations over time. The purpose of this study is to examine the sources of these patterns analysing student achievement in 5 domains across Years 3, 5 and 7. The analysis is of longitudinal population data of over 22,000 students and utilizes fixed-effects models to incorporate stable general and domain-specific latent factors. These latent factors correspond to a general cognitive-ability-like factor and specific aptitudes in particular, or types of, subject areas. The preferred model incorporates both general and domain-specific latent factors with stronger effects for the general factor, although the domain-specific factors are particularly strong for spelling and numeracy. When taking into account general and domain-specific latent factors, the effects of student’s socioeconomic status (SES) and school SES are trivial.     

How children's creative visual imagination and creative thinking relate to their representation of space

This article explores how creative visual imagination and creative thinking can help children to construct mental models of space. A mixed-method study, integrating quantitative and qualitative approaches and involving 98 five-year-old children (54 girls and 44 boys) demonstrated that creative visual imagination, rather than creative thinking, is linked with the knowledge and understanding of space. These results support the notion that creative visual imagination contributes to improvements in children's understanding of basic astronomical concepts. Interestingly, creative thinking was not associated with understanding and knowledge of cosmic phenomena in models taking into account creative imagination. The qualitative analysis showed differences in children's representations of space. We discuss the consequences of these findings for science education, particularly the teaching of elementary astronomy.     

高职教育导师制：意义，模式和应注意的问题

社会发展对高职教育提出更高的要求。本文从高职教育要构建新的人才培养模式出发，阐述高职教育实施导师制的意义、可运作的模式和应注意的问题。     

Can research on science learning and instruction inform standards for science education?

We contrast the current science education reform effort with the reforms of the 1960s and suggest how the current effort could be enhanced. We identify insights from recent research that we believe can inform the reform process, in particular, to reach all science students and also impart a cohesive view of science. We propose an alternative models view of scientific explanation and show how this view would contribute to reforms of (1) course goals, (2) social aspects of science learning, (3) instructional practices, and (4) roles for technology.This paper summarizes discussions and debates that the authors have had over the last few years. The dialogue stems, in part, from our joint participation in the American Educational Research Association Special Interest Group on Education in Science and Technology (AERA SIG:EST) leadership. This paper communicates the spirit of our thinking and does not necessarily reflect the view of SIG:EST, or any other organization.We gratefully acknowledge the support of National Science Foundation Grant MDR-9253462 in work related to this paper. We appreciate helpful comments from Eileen Lewis and the Computer as Learning Partner group.This material is based upon research supported by the National Science Foundation under grant RED-9155744. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and not necessarily reflect the views of the National Science Foundation.     

NTM方法在非线性贝叶斯动态模型中的应用

将NTM方法应用于非线性贝叶斯动态模型，给出了它的递推公式以及随机变量的数字特征的计算，与蒙特卡洛方法相比提高了效率和精度.