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1.
Wind tunnel experiments were conducted, in particular focusing on slow unsteady variations of aerodynamic forces as a potential
cause of the knuckle effect of a new soccer ball (Teamgeist) under non-spinning condition. The experiments included simultaneous
measurements of the drag, the side force and the surface pressure on a ball surface, and the tuft visualisation to investigate
the flow field behind a ball. Of particular interest was the erratic nature of the knuckle effect resulting from the unsteady
movement of vortical wake structure in the supercritical Reynolds number regime. A simple 2-D numerical simulation of the
ball flight trajectory was performed by taking into account the unsteady side force data measured in the present experiments. 相似文献
2.
When we consider the gap between mathematics at elementary and secondary levels, and given the logical nature of mathematics
at the latter level, it can be seen as important that the aspects of children's logical development in the upper grades in
elementary school be clarified. In this study we focus on the teaching and learning of “division with decimals” in a 5th grade
classroom, because it is well known to be difficult for children to understand the meaning of division with decimals, caused
by certain conceptions which children have implicitly or explicitly. In this paper we discuss how children develop their logical
reasoning beyond such difficulties/misconceptions in the process of making sense of division with decimals in the classroom
setting. We then suggest that children's explanations based on two kinds of reversibility (inversion and reciprocity) are
effective in overcoming the difficulties/misconceptions related to division with decimals, and that they enable children to
conceive multiplication and division as a system of operations. 相似文献
3.
大学的治权:理念和资金的关系 总被引：3，自引：0，他引：3
大学面临着一个混乱的时代，许多国家的大学都为数量、质量、治权和经营的问题所困扰。本试图从分析大学理念和资金的关系入手，解剖大学治权的深层结构、所存在的问题和未来发展的方向。 相似文献
4.
从“科学之科学”到“政策之科学” 总被引：2，自引：1，他引：1
由于纵观科学结构的所谓“科学之科学”（Science of Science）正转向“科学政策之科学”（Science of Policy）的新方向,为此可以认为,纵观科学结构的科学地图（science map）将移向科学结构中包含的纵览政策的政策地图（policy map）方向。在此背景下,基于科学根据（evidence）的政策制定可以确保其透明性。文章通过应用日本科学技术振兴机构（简称JST）构建的专利和论文整合检索系统（PATLISYS—J）,介绍世界科学结构的可视化,以及将任意研究者详细分析等进行可视化的方法。 相似文献
5.
Sri Rahayu David F. Treagust A.L. Chandrasegaran Masakazu Kita Suhadi Ibnu 《Research in Science & Technological Education》2013,31(2):169-188
This study investigated Indonesian and Japanese senior high-school students’ understanding of electrochemistry concepts. Sample The questionnaire was administered to 244 Indonesian and 189 Japanese public senior high-school students. Design and methods An 18-item multiple-choice questionnaire relating to five conceptual categories (reactions occurring during electrolysis, differences between electrolytic and voltaic cells, movement of ions in voltaic cells, poles in voltaic cells, voltaic cell reactions) was administered. Results The findings of this study show that difficulties and alternative conceptions previously reported in the literature are held equally by students from a developing and developed country, Indonesian and Japan respectively. Conclusions Collectively, the findings suggest that students’ understanding of electrochemistry concepts is relatively weak. Students from both samples shared common difficulties and displayed several alternative conceptions dealing with electrolysis, electricity flow, the voltaic cell and the electrode reactions. Not surprisingly, the students displayed limited consistency in understanding of the concepts in the five categories. This study has implications for teaching and learning, particularly in classroom discussions using models and computer animations in order to reinforce understanding at the sub-microscopic level. 相似文献
6.
The Shosoin treasures, which include the belongings of Emperor Shomu (CE 701–756) and Empress Komyo (CE 701–760), have an honorable origin and have been continuously handed down for generations since the eighth century in the Todaiji temple in Nara, Japan. Some of the beautiful artifacts found among the treasures display the bachiru carving technique, in which a delicate pattern is produced by carving dyed ivory or antler using additional painting. To elucidate the colorants used for dyeing and painting in the bachiru technique, non-invasive scientific analyses using fiber optic reflectance spectrometry in the visible region, X-ray fluorescence spectroscopy, and X-ray diffraction were performed for eight treasures: a go game board, two go pieces, a nyoi (ritual nail pole), a kugo harp, a bird-shaped accessory, a kaburaya arrow, and a ritual ruler. Second derivatization of the reflectance spectra led to characterization of the dyes in the treasures as sappanwood, lac, madder, gromwell, and indigo. Lac and atacamite were respectively identified in the red and green areas of the painting by reflectance spectrometry and X-ray diffractometry. These results indicated the use of a variety of colorants for the bachiru carving technique in the eighth century. 相似文献
7.
Sri Rahayu Masakazu Kita 《International Journal of Science and Mathematics Education》2010,8(4):667-688
This study investigated Indonesian and Japanese students’ understandings of macroscopic and submicroscopic levels of representing
matter and its changes and the difficulties they have with these concepts. A multiple-choice questionnaire was constructed
and delivered to 447 Indonesian and 446 Japanese public senior high school students. The data were analyzed using quantitative
and qualitative methods. The findings of the study show students’ understandings of macro- and submicroscopic levels are stronger
for higher-grade levels, except that the Indonesian students’ pattern is slightly different. The average percentage of students
responding correctly on the macroscopic level ranges between 62% and 69% (Indonesia) and between 58% and 73% (Japanese), whereas
on the submicroscopic level ranges between 56% and 62% (Indonesian) and 44% and 66% (Japanese). Their understandings of the
macroscopic level, however, are higher than for the submicroscopic level. The soundness of students’ understandings of the
concepts increases with grade level, except for Indonesian pattern slightly different. The average percentage of students
responding correctly ranges between 37% and 48% (Indonesian) and between 28% and 52% (Japanese). Furthermore, students’ level
of sound understandings of the concepts is lower than their understandings on either the macroscopic level or the submicroscopic
level. It is found that students have great difficulties with and hold some alternative conceptions of the concepts of homogeneous
mixtures, phase changes from solid to liquid, and phase changes from solid to gas. The study has implications, for example,
the use of several routes to meaningful learning and the careful use of technical words. 相似文献
8.
日本式雇佣制度和大学生就业 总被引：4，自引：0，他引：4
本文从不同角度分析1960年以后日本不同学历的劳动市场的变化过程。在此基础之上，回顾了高等教育的经济分析、日本的雇佣制度与学历主义关系、科学技术与高等教育的关系等三方面的研究成果。最后，对过去的研究进行评价，并展望了日本大学毕业生就业的未来。 相似文献
9.
10.
Sri Rahayu A. L. Chandrasegaran David F. Treagust Masakazu Kita Suhadi Ibnu 《International Journal of Science and Mathematics Education》2011,9(6):1439-1458
This study was a mixed quantitative–qualitative research to evaluate the efficacy of a designed student-centred instructional
(DSCI) program for teaching about acids and bases. The teaching innovation was designed based on constructivist, hands-on
inquiry and context-based approaches and implemented in seven 45-min lessons with a class of 36 grade 11 students (experimental
group) from a public senior high school in Indonesia. Another class of 38 students (comparison group) from the same school
was instructed using a traditional teacher-centred approach. Data were obtained using a (1) 12-item achievement test on acids
and bases that was administered to both groups as a pretest and a posttest, (2) self-evaluation 13-item questionnaire on students’
perceptions of their competence and confidence in carrying out the inquiry activities that was administered to the experimental
group and (3) 3-item open-ended questionnaire on students’ perceptions of the instructional process using the DSCI that was
administered to the experimental group. The results of the study showed that the teaching innovation was effective in improving
students’ understanding of acid–base concepts with significant difference between the two groups on the posttest mean scores.
Moreover, the effectiveness of the innovation was supported by an increase in students’ interest in learning science as indicated
by their (1) positive perceptions of their engagement and competence in doing inquiry activities, (2) positive perceptions
of the learning environment and (3) positive outcome expectations. The findings have implications for chemistry teaching in
any institution with similar achieving students as well as for the professional development of teachers. 相似文献