Advanced aerostatic analysis of long-span suspension bridges     

张新军 《浙江大学学报(A卷英文版)》2006,7(3):424-429

INTRODUCTION Two examples of the great progress achieved inrecent decades in the design and construction oflong-span suspension bridges are the Akashi KaikyoBridge (1990 m) in Japan and the Great Belt Bridge(1624 m) in Denmark. Into the 21st century, longersuspension bridges are being planned, such as theMessina strait bridge in Italy (3300 m), and the Gi-braltar bridge between Spain and Morocco (5000 m)(Astiz, 1998), etc. In China, five large strait crossingprojects have been planne…  相似文献   

Measuring the relationship between scores on two questionnaires     

John T.E. Richardson   《Educational Research Review》2007,2(1):13-27

Characterising the relationship between participants’ scores on two different questionnaires is a common problem in educational research. The complement of the statistic known as Wilks’ Λ (lambda) measures the amount of variance shared between the scores obtained by the same group of participants on two sets of variables. (1 − Λ) is symmetric, in that it yields the same outcome whichever of the two sets is defined as the dependent variables. Other measures of shared variance have been proposed, but they are systematically conservative in comparison with (1 − Λ). In particular, measures of redundancy underestimate the proportion of shared variance because they fail to take into account the multivariate properties of the data. In short, (1 − Λ) can be commended for use as a measure of the strength of the association between the scores obtained on two questionnaires.  相似文献   

3～6岁儿童心理旋转能力的发展研究     

刘秀环  钱文  林泳海 《幼儿教育》2007,(2)

儿童心理旋转能力的发展特征研究对于早期教育来说具有重要的价值和意义。采用不同的刺激材料考察儿童心理旋转能力的研究结果表明,3～4岁儿童不具有心理旋转能力,4～5岁儿童开始形成心理旋转能力,大部分5～6岁儿童已具有对图形的旋转能力。4～6岁儿童的旋转能力存在性别差异,但未达到显著性水平。在不同的刺激材料上得分存在显著性差异。因此,我们应根据儿童的发展特点来设置课程,在游戏和生活中培养儿童的空间知觉能力,提倡个性化教育。  相似文献   

试论肇庆市城市空间形态的优化     

张成币 《西江大学学报》2006,27(2):88-92

从分析肇庆城市空间形态的形成与发展入手，试图寻找影响和主导肇庆城市空间形态形成的主要因素；在此基础上，进一步剖析肇庆城市空间形态的特征和目前存在的问题，并从城市空间形态的外部空间环境以及内部运行2个层次，提出城市空间形态优化的思路．  相似文献   

渭河下游冲淤变化与潼关高程的关系分析     

姚胜利 《杨凌职业技术学院学报》2006,5(4):20-22

对渭河下游河势及水文状况的多年变化情况进行了介绍和分析,分析认为三门峡水库的修建,使渭河水流变缓,挟沙能力降低,中游大量泥沙在渭河入黄河口大量堆积,造成潼关高程显著抬升,渭河水平面升高,这是渭河下游淤积严重的重要原因。洪水期渭河过流能力急剧减小,防洪能力十分严峻。通过资料分析表明,渭河各段淤积量与潼关高程呈现出一种线形相关规律,由此得出降低三门峡水库运行水位,从而降低潼关高程,减小渭河下游泥沙淤积,提高渭河过水能力,对渭河流域防洪减灾有重要的现实意义。  相似文献   

改进的分子连接性指数与原子化热之间的关系     

文茜  吴永兰 《湘南学院学报》2006,27(2):49-55

本文在链烷烃的分子图的基础上,切断分子图的任一条边(C-C键)成两个子图,以切断边的顶点为起点,对这两个子图的路径顶点数Nc(即子图中任一顶点到起始顶点这一路径中所包含的顶点数)的平方倒数求和(∑1N2c)然后进一步构造出两类新的拓扑指数———邻接矩阵特征根(X1cc,X2cc),距离积方根连接性指数和(Xc);同时,本文探讨了这些指数与相应链烷烃的原子化热(HA)的关系,结果表明本文所提出的拓扑指数与相应的链烷烃的原子化热(HA)具有良好的结构———性质相关性.  相似文献   

三明区域旅游规划空间布局方法研究     

罗金华 《三明学院学报》2007,24(3):272-277

旅游地空间规划布局的理论研究，国内外均有所涉及，但尚未形成较为系统的理论体系，具体规划方法的研究则更少。探讨三明区域旅游“一带二区二窗口”空间布局的规划，提出区域旅游空间布局“系统——分异——集聚”的基本方法，科学合理地协调三明区域旅游空间结构和产品结构，具有一定的实用价值。以“生态三明，中国绿都”为主题形象统领的三明“一带二区二窗口”旅游空间布局，较好地实现了区域特色突出、分区景观各异、产品互补、功能独立、有机联系、结构优化的规划目的。  相似文献   

γB(x)、γB(m)和γB(c)之间的相互关系     

李德江  傅和青 《黄冈师范学院学报》2001,21(5):68-69

导出了同一溶质具有不同浓度标度的各不相同的活度系数之间的相互关系。  相似文献   

Factorial Validity of Student Ratings of Instruction     

Robert?D.?RenaudEmail author  Harry?G.?Murray 《Research in higher education》2005,46(8):929-953

This study tested the Systematic Distortion Hypothesis by examining the factorial validity of student ratings of university teaching. Factorial validity is defined as the degree to which covariance among judged traits resembles the actual or true covariation of observable behaviors underlying these traits. Although many studies have examined the factorial validity of ratings, results are inconsistent. The present study used a more complete methodology to address some of the limitations of previous studies. Student ratings of teaching and measurements of actual teaching behaviors were obtained for 32 instructors. Student ratings were compared to frequency counts of actual teaching behaviors obtained from videotape and to students’ similarity judgments of teacher characteristics. It was found, first, that the structure of student ratings showed a moderately strong relation to the structure of actual behaviors, and a somewhat stronger relation to the structure of conceptual associations; and second, that the effects of systematic distortion were more pronounced for low-inference student ratings than for high-inference ratings.  相似文献   

湖南省城镇空间布局探讨     

谢守红 《衡阳师范学院学报》2002,23(6):89-92

优化城镇空间布局是推进城市化进程,提高城市化质量的重要内容。针对湖南城镇分布现状及存在问题,提出未来城镇空间布局应充分考虑高速公路的联结作用,采取点轴布局模式,重点建设“一核一纵三横”城镇群和城镇带,形成掌状结构,以更好地带动全省城镇地域系统的发展,最后,提出优化城镇空间布局的政策措施。  相似文献