首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
3.
This article addresses and attempts to refute several of the most widespread and enduring misconceptions held by students regarding the enterprise of science. The ten myths discussed include the common notions that theories become laws, that hypotheses are best characterized as educated guesses, and that there is a commonly-applied scientific method. In addition, the article includes discussion of other incorrect ideas such as the view that evidence leads to sure knowledge, that science and its methods provide absolute proof, and that science is not a creative endeavor. Finally, the myths that scientists are objective, that experiments are the sole route to scientific knowledge and that scientific conclusions are continually reviewed conclude this presentation. The paper ends with a plea that instruction in and opportunities to experience the nature of science are vital in preservice and inservice teacher education programs to help unseat the myths of science.  相似文献   

4.
This is a brief account on how we have entertained ourselves in the last two years, that is, a summary of the results we have obtained in a joint work with E. Csáki, M. Csörg? and P. Révész on random walks on a comb.  相似文献   

5.
6.
7.
8.
9.
10.
关于我国2010年人口普查事后质量检查样本量测算的建议   总被引:1,自引:0,他引:1  
同以往历次进行的人口普查一样,我国在2010年第六次人口普查后也将进行事后质量检查。样本量估计是抽取事后质量检查样本之前必须要做的一项工作。本人建议,用2000年人口普查事后质量检查样本资料估计其抽样方案的设计效应,然后用这个设计效应估计2010年在既定精度要求下所需要的样本量。  相似文献   

11.
For a graph property P, the edit distance of a graph G from P, denoted EP(G), is the minimum number of edge modifications (additions or deletions) one needs to apply to G to turn it into a graph satisfying P. What is the furthest graph on n vertices from P and what is the largest possible edit distance from P? Denote this maximal distance by ed(n,P). This question is motivated by algorithmic edge‐modification problems, in which one wishes to find or approximate the value of EP(G) given an input graph G. A monotone graph property is closed under removal of edges and vertices. Trivially, for any monotone property, the largest edit distance is attained by a complete graph. We show that this is a simple instance of a much broader phenomenon. A hereditary graph property is closed under removal of vertices. We prove that for any hereditary graph property P, a random graph with an edge density that depends on P essentially achieves the maximal distance from P, that is: ed(n,P) = EP(G(n,p(P))) + o(n2) with high probability. The proofs combine several tools, including strengthened versions of the Szemerédi regularity lemma, properties of random graphs and probabilistic arguments. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008  相似文献   

12.
Our theory of collective motions of open system [2,3] is generalized to the case of systems distributed inm-dimensional space. We propose a rigorous definition of a particle in terms of systems theory. A concrete image of a particle, conceived as a localized collective entity in Space, is obtained. It turns out that wave-corpuscle duality is nothing else but a simple consequence of general equations of collective motions: particles appear at the output as collective manifestations of inner states, and waves appear at the input as guiding waves of particles.The David and Helena Zlotowski chair in Operator Theory and Systems Theory.  相似文献   

13.
《大学数学》2016,(6):58-64
分析了大学《经济数学》教学中存在的问题,论述了主动学习的重要性,探索了在教学中激发学生主动学习的策略与方法,提出了让学生愿学、乐学、善学、学会的思路与方法,启发了激发学生主动学习的一些做法的思考.  相似文献   

14.
15.
In this paper is reported the extent of textbook use by 39 middle school mathematics teachers in six states, 17 utilizing a textbook series developed with funding from the National Science Foundation (NSF‐funded) and 22 using textbooks developed by commercial publishers (publisher‐generated). Results indicate that both sets of teachers placed significantly higher emphasis on Number and Operation, often at the expense of other content strands. Location of topics within a textbook represented an oversimplified explanation of what mathematics gets taught or omitted. Most teachers using an NSF‐funded curriculum taught content intended for students in a different (lower) grade, and both sets of teachers supplemented with skill‐building and “practice” worksheets. Implications for documenting teachers' “fidelity of implementation” ( National Research Council, 2004 ) are offered.  相似文献   

16.
Extracurricular science-related experiences of young students were examined. The sample consisted of 539 elementary school students between the ages of 9 and 13. Students completed the Science Experiences Survey (SES) to identify the number of common scientific materials and activities they experienced outside of the classroom. The factor analysis isolated three underlying factors of extracurricular science-related experiences: life science-related experiences, physical science-related experiences, and general learning attributes related to science. Further analysis identified differences in reported experiences by gender. The data indicate that young girls tend to participate in nurturing life science-related activities, and young boys favor hands-on, action-oriented physical science-related experiences. The research suggests that the gender disparity in science follows a continuuum that begins with the experiences of elementary school students.  相似文献   

17.
18.
19.
In any subject concerned with rational intervention in human affairs, theory must lead to practice; but practice is the source of theory: neither theory nor practice is prime. We can examine this ‘groundless’ relation by asking what intellectual framework F is applied in what methodology M to what area of application A? If we do this for O.R., systems analysis, systems engineering etc., we see that F and M have changed dramatically between the 1950s and the 1980s, yielding the ‘hard’ and ‘soft’ traditions of systems thinking. The ‘hard’ tradition, based on goal seeking, is examined in the work of Simon and contrasted with the ‘soft’ tradition, based on learning, as exemplified in the work of Vickers and the development of soft systems methodology. The two are complementary, but the relation between them is that the ‘hard’ is a special case of ‘soft’ systems thinking. This analysis makes sense of the recent history of management science and helps to prepare us for the 1990s.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号