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221.
This study applied expectancy theory to integrate the numerous and disparate explanations that researchers and educators have proposed to account for teacher resistance to implementing cooperative learning as an educational innovation. The cooperative learning implementation questionnaire (CLIQ) contained 48 items grouped under three broad motivational categories: perceived value of the innovation, expectancy of success, and perceived cost. These items accounted for 42.3% of the total variance in self-reported use of cooperative learning among 933 teachers. Expectancy of success issues were most important in differentiating users and non-users, suggesting that increased emphasis on professional development should be used to enhance teachers' beliefs that they can succeed in implementing an innovation in their own context. This may require both follow-up support and adaptation of the innovation. 相似文献
222.
Parental reactions to children's negative emotions: longitudinal relations to quality of children's social functioning 总被引:7,自引:0,他引:7
Relations between self-reported parental reactions to children's negative emotions (PNRs) and children's socially appropriate/problem behavior and negative emotionality were examined longitudinally. Evidence was consistent with the conclusion that relations between children's externalizing (but not internalizing) emotion and parental punitive reactions to children's negative emotions are bidirectional. Reports of PNRs generally were correlated with low quality of social functioning. In structural models, mother-reported problem behavior at ages 10-12 was at least marginally predicted from mother-reported problem behavior, children's regulation, and parental punitive or distress reactions. Moreover, parental distress and punitive reactions at ages 6-8 predicted reports of children's regulation at ages 8-10, and regulation predicted parental punitive reactions at ages 10-12. Father reports of problem behavior at ages 10-12 were predicted by earlier problem behavior and parental distress or punitive reactions; some of the relations between regulation and parental reactions were similar to those in the models for mother-reported problem behavior. Parental perceptions of their reactions were substantially correlated over 6 years. Some nonsupportive reactions declined in the early to mid-school years, but all increased into late childhood/early adolescence. 相似文献
223.
Because the counseling profession places high value on counselors possessing accurate self-awareness, this study investigated the differences and relationships between counselor education students' self-perceived and measured needs levels. A sample of 107 counselor students estimated their needs levels and then completed the Personality Research Form (PRF). Significant differences between their perceived and measured needs levels were found for 10 of the 14 PRF scales. Wide variations were evident in both perceived and measured needs levels. Significant correlations between perceived and measured needs levels percentiles for all 14 scales indicated consistency in over or under estimation of needs levels. Age and number of quarter hours completed were generally unrelated to accuracy of needs level estimation. 相似文献
224.
Jacob MC Sturkenboom D 《Isis; an international review devoted to the history of science and its cultural influences》2003,94(2):217-252
The Natuurkundig Genootschap der Dames (Women's Society for Natural Knowledge), formally established by and for women, met regularly from 1785 to 1881 and sporadically until 1887. It challenges our stereotypes both of women and the physical sciences during the eighteenth century and of the intellectual interests open to women in the early European republics. This essay aims not simply to identify the society and its members but to describe their pursuits and consider what their story adds to the history of Western science. What does this society's existence tell us about the relationship between women and early science in general and about science and society in the Dutch setting in particular? Science and gender look rather different when observed through the activities of the immensely prosperous women of Middelburg, citizens of one of the most highly literate Western countries. The elite lives of the first-generation members of the women's society also offer us a glimpse into the early domestication of science, a process vital to its acceptance and assimilation. 相似文献
225.
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227.
Paul C. Kainen 《Journal of The Franklin Institute》2004,341(4):391-399
It is shown that cartesian product and pointwise-sum with a fixed compact set preserve various approximation-theoretic properties. Results for pointwise-sum are proved for F-spaces and so hold for any normed linear space, while the other results hold in general metric spaces. Applications are given to approximation of Lp-functions on the d-dimensional cube, 1?p<∞, by linear combinations of half-space characteristic functions; i.e., by Heaviside perceptron networks. 相似文献
228.
Cross-lingual semantic interoperability has drawn significant attention in recent digital library and World Wide Web research as the information in languages other than English has grown exponentially. Cross-lingual information retrieval (CLIR) across different European languages, such as English, Spanish, and French, has been widely explored; however, CLIR across European languages and Oriental languages is still in the initial stage. To cross language boundary, corpus-based approach is promising to overcome the limitation of the knowledge-based and controlled vocabulary approaches but collecting parallel corpora between European language and Oriental language is not an easy task. Length-based and text-based approaches are two major approaches to align parallel documents. In this paper, we investigate several techniques using these approaches and compare their performances in aligning English and Chinese titles of parallel documents available on the Web. 相似文献
229.
C.S. Badue R. Baeza-Yates B. Ribeiro-Neto A. Ziviani N. Ziviani 《Information processing & management》2007
The performance of parallel query processing in a cluster of index servers is crucial for modern web search systems. In such a scenario, the response time basically depends on the execution time of the slowest server to generate a partial ranked answer. Previous approaches investigate performance issues in this context using simulation, analytical modeling, experimentation, or a combination of them. Nevertheless, these approaches simply assume balanced execution times among homogeneous servers (by uniformly distributing the document collection among them, for instance)—a scenario that we did not observe in our experimentation. On the contrary, we found that even with a balanced distribution of the document collection among index servers, correlations between the frequency of a term in the query log and the size of its corresponding inverted list lead to imbalances in query execution times at these same servers, because these correlations affect disk caching behavior. Further, the relative sizes of the main memory at each server (with regard to disk space usage) and the number of servers participating in the parallel query processing also affect imbalance of local query execution times. These are relevant findings that have not been reported before and that, we understand, are of interest to the research community. 相似文献
230.