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211.
This is a study of the development trend of creative scientific problem finding (CSPF) ability of a sample of 1,367 elementary, middle, and high school students in two Chinese cities. Students were instructed to generate science related questions in both open and closed conditions with responses scored for Fluency, Flexibility, and Originality. Results suggest that CSPF ability has a developmental trend characterized by a significant leap in the 5th grade, followed by a steady advance until it peaked in the 8th grade, and then declined and stabilized in the high school years (9th–11th grades). No difference between male and female students was found. The type of instruction showed significant differential influence on CSPF and its development. 相似文献
212.
126 leaders and 624 employees were sampled to test the relationship between sources of motivation and conflict management styles of leaders and how these variables influence effectiveness of leadership. Five sources of motivation measured by the Motivation Sources Inventory were tested-intrinsic process, instrumental, self-concept external, self-concept internal, and goal internalization. These sources of work motivation were associated with Rahim's modes of interpersonal conflict management-dominating, avoiding, obliging, complying, and integrating-and to perceived leadership effectiveness. A structural equation model tested leaders' conflict management styles and leadership effectiveness based upon different sources of work motivation. The model explained variance for obliging (65%), dominating (79%), avoiding (76%), and compromising (68%), but explained little variance for integrating (7%). The model explained only 28% of the variance in leader effectiveness. 相似文献
213.
Discontinuous precipitation in a two-phase Zn-rich Zn-6.3at.%Ag alloy has been studied. It has been shown that the eta/epsilon interphase boundaries have the ability to initiate discontinuous precipitation as do the eta/eta grain boundaries. The back-polishing method is used to show the interconnection between a discontinuous precipitate colony and the eta/epsilon interphase boundary. The reaction front velocity of discontinuous precipitation initiated at the eta/eta grain boundary is 12-90% higher than that of discontinuous precipitation initiated at the eta/epsilon interphase boundary under various ageing temperatures. 相似文献
214.
We present an analysis and results on the homogeneous nucleation of a dislocation loop under stress in a perfect crystal. By using a variational boundary integral method in the Peierls-Nabarro framework, we have determined the saddle-point configurations of embryonic dislocation loops and their associated activation energies under stress levels up to the ideal shear strength. The high-energy barriers under the usual levels of applied shear stresses, differing markedly from the ideal shear strength, confirm the widely held view that thermal motion should play no role in such nucleation. The result provides means for more definitive solutions of fundamental problems involving homogeneous nucleation of dislocation loops and has significant implications for models based on the mechanism of nucleation of dislocations from a perfect crystal. 相似文献
215.
Lin Shi 《The American journal of family therapy》2013,41(3):198-211
The study examined the prevalence of five types of childhood trauma in a sample of adult clients (n = 497) as well as their long-term relation to trauma symptoms in adulthood. Results showed a high prevalence of abuse and neglect with emotional abuse and neglect being the most common ones. Emotional abuse was the best and strongest predictor of trauma symptoms in adulthood, including anxiety, depression, defensive avoidance, as well as internal confusion and emptiness. The results indicated that experience of emotional abuse is no less significant than that of physical and sexual abuse in its long-term impact. Clinical implication was provided. 相似文献
216.
Ming Xu 《Studia Logica》2013,101(3):583-599
This paper proves the finite model property and the finite axiomatizability of a class of normal modal logics extending K4.3. The frames for these logics are those for K4.3, in each of which every point has a bounded number of irreflexive successors if it is after an infinite ascending chain of (not necessarily distinct) points. 相似文献
217.
Xu Yibao 《逻辑史和逻辑哲学》2013,34(3):181-196
Bertrand Russell was one of the most prominent figures in the formation and development of mathematical logic. It is widely acknowledged that his work in this field exerted tremendous influence in the West, especially in the first three decades of the twentieth century. The important role he played in inspiring Chinese interest in this subject, however, is virtually unknown. This paper describes Russell's contributions to the introduction of mathematical logic in China through a discussion of his lectures in Beijing in March of 1921, and the subsequent Chinese translations of his Introduction to Mathematical Philosophy and Principia Mathematica. 相似文献
218.
X.G. Zheng N. Tsutsumi S. Tanaka M. Suzuki S. Nishioka C.N. Xu 《Philosophical Magazine Letters》2013,93(10):819-825
Electrical resistivity, thermoelectric power, magnetic susceptibility and calorimetric measurements were carried out on a single crystal of CuO. In addition the two known antiferromagnetic transitions between 210K and 230K, a new phase transition around 160K was found in CuO. The experimental results show that this new transition is related to changes in the electronic state of CuO. 相似文献
219.
Lewis的临时内在性问题出名地难以理解,也许是因为它质疑了某些我们认为理所当然的基本概念。本文通过简明地陈述问题和对若干可能解法的分析试图使之易于理解。此外,本文给出了一个产生Bradley倒退的简明易懂的方法。 相似文献
220.