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排序方式: 共有4512条查询结果,搜索用时 31 毫秒
41.
韩礼德系统语法语言分析的模式   总被引:3,自引:0,他引:3  
:语言可以从不同角度加以研究。该文从六个方面简单阐述了系统语法大师M .A .K .Halliday语言分析的模式 ,主要内容包括 :语言的层次 ,链轴和选择轴 ,语法结构 ,语法单位 ,语法的级阶和语法系统  相似文献   
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This paper presents an adaptive strategy for controlling chaotic systems. By employing the phase space reconstruction technique in nonlinear dynamical systems theory, the proposed strategy transforms the nonlinear system into canonical form, and employs a nonlinear observer to estimate the uncertainties and disturbances of the nonlinear system, and then establishes a state-error-like feedback law. The developed control scheme allows chaos control in spite of modeling errors and parametric variations. The effectiveness of the proposed approach has been demonstrated through its applications to two well-known chaotic systems: Duffing oscillator and Rössler chaos.  相似文献   
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In Japan, there has been an increased concern about family and community participation in the childs education. Traditionally, the role of parents and community in Japan has been one of support and less one of active involvement in school learning. Since the government commenced education reforms in the last quarter of the 20th century, a more active role for parents and the community in education has been encouraged. These reforms have been inspired by the need to tackle various problems that had arisen, such as the perceived harmful elements of societys preoccupation with academic achievement and the problematic behavior of young people. In this paper, the following issues are examined: (1) education policy and reform measures with regard to parent and community involvement in the childs education; (2) the state of parent and community involvement at the eve of the 20th century.  相似文献   
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This study explored the role of student (e.g., age, language background, gender), home (e.g., parent/caregiver education), and school (e.g., school type, size) socio-demographic factors in students’ school (e.g., in-school arts tuition, arts engagement), home (e.g., parent/caregiver–child arts interaction), and community (e.g., arts attendance, arts tuition) arts participation. The sample comprised 1172 elementary and secondary school students from 15 schools. Findings revealed that student and home socio-demographic factors were the most salient in predicting arts participation across school, home, and community contexts. Age, gender, and prior achievement were the key student socio-demographic factors, while parent/caregiver education and occupation were also associated with students’ arts participation. Implications for practice and intervention pertinent to young people’s arts participation are discussed.  相似文献   
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This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献   
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