Two categories of e-learning in Japan     

Minoru Nakayama  Rowena Santiago 《Educational technology research and development : ETR & D》2004,52(3):100-111

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Activity of metalloproteinases and adiponectin in obese patients— a possible factor of incisional hernias after bariatric procedures     

Wojciech Szczęsny  Magdalena Kuligowska-Prusińska  Stanisław Dąbrowiecki  Jakub Szmytkowski  Adrian Reśliński  Maciej Słupski 《Journal of Zhejiang University. Science. B》2018,19(1):65-70

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The elusive nature of whole system improvement in education     

Michael Fullan 《Journal of Educational Change》2016,17(4):539-544

Whole system improvement—where the vast majority of schools improve—is difficult to achieve. Some jurisdictions use what turns out to be ‘wrong’ policy drivers like testing and evaluation. Rather, success turns out to depend on changing the culture of schools and their relationship to the infrastructure of policies and regulation. I examined the six cases studies in the light of whole system change criteria. Two of the case studies, South Africa and India, represent limited but useful examples in that they focus on basic skills like literacy. A second set of two studies, Escuela Nueva and LCP in Mexico, represent strong examples of how bottom up strategies can spread to significant levels. The final two, Long Beach in the US and Ontario, are strong examples of how deep change can be accomplished by focusing on a few core priorities and then building a culture over a number of years to support and sustain the changes. The paper then draws conclusions about the conditions that will be required for large scale change to occur.  相似文献   

一种用于宽动态范围上的高精度散射测量的标准方法     

赵恒凯  方振和  姚传亮  蔡春富  章俊 《上海大学学报(英文版)》2003,7(3):246-250

The co-effect of transmitted power fluctuation and system nonlinearity produce deviations in scatterometer measurement results . An internal calibration method to deal with this problem is proposed. The method can result in more precise scatterometric measurements in a wide range. The basic principle of the method is combining real-transmitted-power detection with the calibration of system nonlinearity. A practical scheme to implement the method is also presented, which is developed based on a special designed mechanism of a microwave radiometer-scatterometer combined system.  相似文献   

The rewarding effects of number and surface area of food in rats     

Devina Wadhera  Lynn M. Wilkie  Elizabeth D. Capaldi-Phillips 《Learning & behavior》2018,46(3):242-255

Visual cues have an important role in food preference for both rats and humans. Here, we aim to isolate the effects of numerosity, density, and surface area on food preference and running speed in rats, by using a forced-choice maze paradigm. In Experiment 1, rats preferred and ran faster for a group of multiple smaller pellets rather than a single large pellet, corroborating previous research (Capaldi, Miller, & Alptekin Journal of Experimental Psychology: Animal Behavior Processes, 15(1), 75–80, 1989). Further experiments tested the prevailing hypothesis that multiple food pieces are more reinforcing because they occupy a larger surface area. Experiment 2 controlled for numerosity by utilizing a continuous food: mashed potatoes flattened to cover a larger surface area or rounded into a ball. The rats preferred and ran faster for the flattened potatoes, suggesting surface area plays a role in quantity estimations. Finally, in Experiment 3, rats displayed no preference or difference in running speed between a group of scattered and clustered pellets when number of pellets were kept constant. Taken together, these results suggest that density has an important role in food perception—that is, the rewarding effect of higher numerosity or larger surface area is removed when the food does not fill out the entire space. Alternative explanations and implications for human diet are discussed.  相似文献   

Using Variables in School Mathematics: Do School Mathematics Curricula Provide Support for Teachers?     

James Dogbey 《International Journal of Science and Mathematics Education》2016,14(6):1175-1196

This study employed content analysis to examine 3 popular middle-grades mathematics curricula in the USA on the support they provide for teachers to implement concepts associated with variables in school mathematics. The results indicate that each of the 3 curricula provides some type of support for teachers, but in a varied amount and quality. More specifically, whereas the University of Chicago School Mathematics Project (UCSMP) curriculum provides support for teachers on several aspects of using variables in school mathematics, the support found in the Connected Mathematics 2 and the Math Connects curricula focused mainly on one conception of variables—namely, the use of variables as quantity that varies in the Connected Mathematics 2 curriculum and the use of variables as specific unknowns in the Math Connects curriculum. Overall, the UCSMP curriculum provides the most support for teachers, followed by the Connected Mathematics 2 curriculum, with the Math Connects curriculum recording the least support for teachers to enact variable concepts. It is worth pointing out that, although the 3 curricula collectively provide guidance for teachers to implement variable ideas within meaningful real-world contexts, the supports identified in the respective curriculum were not sufficient in addressing all of the areas that are essential for teaching the many concepts associated with variables in school mathematics effectively. Recommendations for curriculum developers and for international researchers with interest in the roles of variables in school mathematics are provided.  相似文献   

自聚焦克尔类电介质中非傍轴光束调制非稳的研究     

冯敏  薛云  卫青  施解龙 《上海大学学报(英文版)》2004,8(2):159-163

Propagation stability of non-paraxial beam in nonlinear Kerr media is investigated with a linear stability method.Both theoretical analysis and numerical simulation show that modulation instability(MI) gain spectrum has three different distribution features determined by the times of incident power P0 and the non-paraxial parameter a. Furthermore,the corresponding criterion is put forward to distinguish the three different distributions.  相似文献   

Must stacked cards topple if they overhang?     

Soubhik Chakraborty  Pranvesh Mukherjee  Animesh Mukherjee 《Resonance》2004,9(12):67-69

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Elementary Science: Left Behind?     

Dee Goldston 《Journal of Science Teacher Education》2005,16(3):185-187

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Large amplitude free vibration of a flexible panel coupled with a leaking cavity     

Yiu-yin Lee 《浙江大学学报(A卷英文版)》2017,18(1):75-82

This paper addresses the effect of leakage on the natural frequencies of a large amplitude vibrating panel backed by a cavity, which has not been considered in many other related studies. The structural-acoustic governing equations are employed to study this nonlinear problem. An elliptical integral method, which was recently developed for the nonlinear panel cavity problem, is introduced here to solve for the structural-acoustics responses. The present results agree reasonably well with those obtained from the classical harmonic balance method. Modal convergences of the nonlinear solutions are performed to verify the proposed method. The effects of vibration amplitude and leakage size are studied and discussed. It is found that (1) the edge leakages in a panel cavity system significantly affect the natural frequency properties, and (2) the edge leakages induce a low frequency acoustic resonance.  相似文献