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141.
When identifyinginstruments that have had great influence on the history of physics, none comes to mind more quickly than the pendulum. Though first treated scientifically by Galileo in the 16th century, and in some respects nearly `dead' by the middle of the 20th century; the pendulum experienced `rebirth' by becoming an archetype of chaos. With the resulting acclaim for its surprising behavior at large amplitudes, one might expect that there would already be widespread interest in another of its significant nonlinearities. Such is not the case, however, and the complex motions of small amplitude physical pendula are barely known. The present paper shows that a simply-constructed metallic rod pendulum is capable of demonstrating rich physics in a largely unstudied area.  相似文献   
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The paper describes the design and use of a studio system which arose out of the need to give demonstrations of experimental procedures to practical classes of up to 150 students. Since the requirements could be specified in some detail it was possible to use novel methods of working which turned out to be very efficient and economical.  相似文献   
145.
A broad view of mathematics education takes it as the study of how people learn and do mathematics. Starting with this view, the actual and potential relationships of mathematics education as are search discipline to mathematics as a field of knowledge and activity and to the mathematicians carrying out that activity are analyzed. This leads to the picture of a gulf between the two scientific communities which are based in different cultures of thinking and research. A (meta-)study of mathematics and all its facets termed here mathematicology is proposed. It could serve as common ground for cooperative studies by mathematicians and mathematics educators. Thereby the gulf will not necessarily become narrower but abridge over the differences and mutual misunderstandings could be built.  相似文献   
146.
The common practice of using discussion groups during case-based learning makes the role of discussion important in these learning environments. However, little empirical research has been done to investigate the influence of discussion on performance and motivation in case-based learning. The purpose of this article is to present the results of a study conducted to examine the role of discussion groups in a case-based environment. College students completed two cases either individually or in small discussion groups. Measures included two case analyses, an attitude survey, time on task, and document analysis. Results revealed significant performance and time differences between instructional methods on the first case, but not on the second case. In addition, results indicated significant differences in student attitudes between treatments. Overall, participants who worked in groups liked their method significantly better than those who worked alone, felt they learned more working in a group than they would have working alone, and expressed a preference for working in a group if they had to do the class over again. Implications for implementing case-based learning and future research are discussed. Anna E. Flynn is Vice President and NAPM Associate Professor with the National Association of Purchasing Management.  相似文献   
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This article provides background on national movements toward expanded school mental health (ESMH) programs and school‐based health centers (SBHCs), and presents advantages and challenges of joining these two systems of child and adolescent health care. Delivering ESMH through SBHCs promotes an interdisciplinary approach, health–mental health care integration, and benefits including enhancing referral bases, improving screening of problems, and enhanced confidentiality and privacy. But this integrated approach also presents challenges including managing referrals and significant needs, handling crises, building a focus on prevention and mental health promotion, handling administrative demands, and coping with limited resources. These challenges, ideas for overcoming them, and future directions for this promising service delivery approach are discussed. © 2003 Wiley Periodicals, Inc. Psychol Schs 40: 297–308, 2003.  相似文献   
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In this paper,we prove that the Veronese surface can be determined by the 1-spectrum of the Laplace operator.  相似文献   
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In this paper ,a hybrid approach was developed to investigate the transient responses of a multi-span non-uniform flexble spinning shaft with nonlinear and asymmetric supports.The non-uniform spinning shaft with variable parmeters was modeled as a Bernoulli-Euler beam column with sectional constant cross-section properties by the finite element method.The supporting stiffness behavior of the nonlinear supports was described as a piecewise-linear and asymmetric model.The equations of motion in the matrix form of a multi-span non-uniform spinning shaft with nonlinear and asymmetric supports were formulated using Hamilton‘s principle and the assumed mode method.As an example,a spinning rocket with many variable stiffness supports was numerically simulated by the direct integration method.The transient response and dynamic behavior of this rotate-dynamic system are analyzed.  相似文献   
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