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71.
72.
论大学生体育参与动机的培养 总被引:1,自引:0,他引:1
施亚菊 《宁波工程学院学报》2002,14(1):69-70,79
大学生具有良好的参与动机是实现体育教学目标的一个重要前提条件。本文通过对体育参与动机内涵及影响体育参与动机的心理因素的分析,提出了大学体育教学中如何培养大学生正确的体育参与动机的一些想法,以供广大体育工作者参考。 相似文献
73.
Ramirez Juan R.; Crano William D.; Quist Ryan; Burgoon Michael; Alvaro Eusebio M.; Grandpre Joseph 《Canadian Metallurgical Quarterly》2004,18(1):3
The authors investigated relationships between marijuana and inhalant use and several cultural and demographic factors in Anglo American and Hispanic American adolescents (N=1,094). Outcome measures assessed lifetime and 30-day marijuana and inhalant use. Predictors and covariates used in logistic regression analyses were region, grade, gender, knowledge, acculturation, familism, and parental monitoring. Hispanic Americans exhibited higher usage across all measures. In this group, high acculturation was associated with low marijuana, but high inhalant, use. Across all participants, positive family relations and parental monitoring were strongly associated with attenuated marijuana use hut only among those most knowledgeable about drugs. Familism and monitoring were not associated with diminished usage among the less knowledgeable. For inhalants, monitoring combined with high knowledge or high familism was associated with diminished usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
75.
A.P.S. Selvadurai 《Engineering Analysis with Boundary Elements》1996,17(4):287-294
The paper examines the problem of a penny-shaped crack which is formed by the development of a crack in both the fibre and the matrix of a composite consisting of an isolated elastic fibre located in an elastic matrix of infinite extent. The composite region is subjected to a uniform strain field in the direction of the fibre. The paper presents two integral-equation based approaches for the analysis of the problem. The first approach considers the formulation of the complete integral equations governing the associated elasticity problem for a two material region. The second approach considers the boundary integral equation formulation of the problem. Both methods entail the numerical solution of the governing integral equations. The solutions to these integral equations are used to evaluate the stress intensity factor at the boundary of the penny-shaped crack. 相似文献
76.
以往对电站技术供排水系统大都未进行水力平差计算,致使一些实际电站的供排水系统达不到预期的效果,甚至影响机组的正常运行。据此,给出了供排水管网的平差计算方法,有利于正确评估电站管网,另外,提出了管网校核应注意的问题。 相似文献
77.
Hugh S. Fairman 《Color research and application》1995,20(1):44-49
In 1993, the American Society for Testing and Materials carried out a field test of newly calculated tristimulus weighting factors. These weighting factors had been calculated by a method proposed by Venable. the test also included a method of correction for bandpass dependence put forth by Stearns. the purpose of the trial was to assess the possible reduction in bandpass dependence introduced by each of these sets of weights. A large number of sets of spectral data were gathered from the cooperators in the field test. Results of integration by the various sets of tristimulus weighting factors were calculated. A total of 15 120 color differences were calculated and statistics were derived to test the probable error resulting from each method of correction. Errors attributable to bandpass dependence were on the order of a few tenths to as much as one CIELAB unit when uncorrected weight sets were used. These errors could be reduced to a few hundreths of a CIELAB unit, and in some cases to a few thousandths of a unit, by employing one correcting strategy or the other. an overall mix of strategies was ultimately chosen to minimize the bandpass dependence over the entire range of weight sets. Utilizing this mixed strategy, the median error introduced into 10-nm integration by bandpass dependence was only 0.004 CIELAB units. © 1995 John Wiley & Sons, Inc. 相似文献
78.
79.
煤气鼓风机为适应系统煤气量的变化采用改变风机的转速来进行调节是一有效的节能方法。本文介绍了液力偶合器的结构特点、工作原理及其在煤气鼓风机系统中的应用,以实现风机的调速,并取得了明显的节能效果。 相似文献
80.
实证分析:上市公司资本结构的影响因素 总被引:13,自引:0,他引:13
在国内外相关研究的基础上,利用我国资本市场的公开数据,对上市公司资本结构的影响因素进行实证研究,得出了若干重要结论。 相似文献