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61.
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
65.
Sylvia Hurtado June C. Han Victor B. Sáenz Lorelle L. Espinosa Nolan L. Cabrera Oscar S. Cerna 《Research in higher education》2007,48(7):841-887
The purpose of this study is to explore key factors that impact the college transition of aspiring underrepresented minority
students in the biomedical and behavioral sciences, in comparison with White, Asian students and non-science minority students.
We examined successful management of the academic environment and sense of belonging during the first college year. Longitudinal
data were derived from the Higher Education Research Institute’s (HERI) 2004 Cooperative Institutional Research Program (CIRP)
Freshman Survey and the 2005 Your First College Year (YFCY) Survey. Using a reformulation of the integration model (Nora,
Barlow, and Crisp, 2005), we find concerns about college financing, negotiating family support and responsibility, and campus
racial dynamics (perceived and behavioral) affect student adjustment and sense of integration in the first year.
This study was made possible by the support of the National Institute of General Medical Sciences, NIH Grant Number 1 RO1
GMO71968-01. This independent research and the views expressed here do not indicate endorsement by the sponsor. 相似文献
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Marianne?Mansour Andrew?J.?MartinEmail authorView authors OrcID profile Michael?Anderson Robyn?Gibson Gregory?Arief?D.?Liem David?Sudmalis 《The Australian Educational Researcher》2016,43(2):221-244
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
68.
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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da Silva Cláudia Sampaio Corrêa Teixeira Marco Antônio Pereira Cardoso Paulo Fernández-Navarro Pablo Gonçalves Miguel M. Duarte Maria Eduarda 《International Journal for Educational and Vocational Guidance》2020,20(3):635-652
International Journal for Educational and Vocational Guidance - This case study of an undecided university student has two aims: to assess the effect of life design career counselling on... 相似文献