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141.
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积极财政政策对区域经济增长与差异的影响 总被引:11,自引:0,他引:11
本文利用面板数据模型和时变参数模型分别考察了积极财政政策对我国区域经济增长和差异的影响。分析表明,积极财政政策对我国区域经济增长具有较强的促进作用,其中对西部地区的正向影响力度最大,中部地区次之,东部地区最小。积极财政政策并没有有效地缩小我国区域经济差异,反而促使我国区域差异进一步增大,但影响力度逐年减弱。 相似文献
143.
含氮有机化合物疏水常数的量化研究 总被引:5,自引:3,他引:5
采用McRea的理论和London的分散式,结合疏水常数的理论公式,运用量子化学计算研究了146个含氮有机化合物体系,通过多元逐步线性回归关联得一含有三个参数的方程(N=146,S=0.36,F=404.5,R=0.95)。研究发现该类分子的疏水常数与分子的电性具有良好的相关性,但是分子体积的影响也不能忽略。最后对影响含氮有机分子疏水常数的原因进行了分析。 相似文献
144.
应用能量的方法,研究了简支梁的几何参数对动荷载系数的影响,作出了动荷载系数随几何参数变化的曲线。通过实例得到梁在受到横向冲击时,考虑与不考虑梁自身质量情况下,动载荷系数误差较大。结果表明:动荷载系数随梁的高度增大而增大,随梁的长度、质量增大而减小。 相似文献
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随着全球化和科技革命进程的深入,传统的高等教育的改革与创新势在必行。作为一种全新且以共同性与整体性为教育目标的通识教育,日益受到各国高等教育界的重视。着重介绍全球化视角下,美国哈佛大学通识教育在理念、目标、基本框架和具体举措等方面所呈现的特色,以期为推动我国高等教育的改革和发展,培养创新型人才提供借鉴和启示。 相似文献
147.
We develop and propose a new counting method at the aggregate level for contributions to scientific publications called modified fractional counting (MFC). We show that, compared to traditional complete-normalized fractional counting, it eliminates the extreme differences in contributions over time that otherwise occur between scientists that mainly publish alone or in small groups and those that publish with large groups of co-authors. As an extra benefit we find that scientists in different areas of research turn out to have comparable average contributions to scientific articles. We test the method on scientists at Norway’s largest universities and find that, at an aggregate level, it indeed supports comparability across different co-authorship practices as well as between areas of research. MFC is thereby useful whenever the research output from institutions with different research profiles are compared, as e.g., in the Leiden Ranking. Finally, as MFC is actually a family of indicators, depending on a sensitivity parameter, it can be adapted to the circumstances. 相似文献
148.
An increasing number of instructors are seeking to provide students with online anatomy resources. Many researchers have attempted to identify associations between resource use and student learning but few studies discuss the importance of usability testing in resource design and modification. Usability testing provides information about ease of use and resource flexibility and indicates navigational issues that contribute to extraneous cognitive load for the user. An example of usability testing for modification of an online anatomy resource called the "Virtual Lab" is presented. Usability testing was used to determine whether increased content would impair navigation through the interface. Subjects with varying levels of experience with anatomy content were recruited to assess efficiency and effectiveness (defined by usability standards) of the original resource and of the redesigned resource. Comparisons between usability evaluation of the original "Virtual Lab" (OVL) and of the redesigned "Virtual Lab" (RVL) revealed that subjects were better able to successfully complete tasks using the RVL than they were with the OVL. Results also demonstrated that subjects did not take significantly more time to successfully complete tasks with the RVL. Additionally, usability testing revealed that subjects were able to successfully complete tasks using the RVL regardless of whether they possessed prior experience with anatomy content or not. Results of this study suggest that the modified resource is more effective for users. The example presented here underscores the need for usability testing prior to resource implementation and whenever significant changes are made to a resource interface. 相似文献
149.
人类和所有的动物一样都存在着攻击性,这是由生物性所决定的,是人类与生俱来的能力。论述了人类攻击性与体育运动的关系,体育运动运用其独有的方式宣泄着人类的攻击性,从攻击性的视角提出了促进体育运动和谐发展的对策。 相似文献
150.