The elusive nature of whole system improvement in education

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.     

一种用于宽动态范围上的高精度散射测量的标准方法

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.     

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

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.     

试论在数学教学中如何培养民族学生的创新意识

创新是一个民族的灵魂。实施素质教育的关键和重点就是要不遗余力地着力培养学生的创新能力,让学生的个性思维得到充分全面的发展,这是当前教育工作者积极探索的重要课题。本文从发挥民族学生创造潜能,培养其多角度思考问题,积极探索创新等方面出发,就数学教学如何培养民族学生的创新意识进行了认真探讨。     

网络环境下的学校管理

章旨在探讨校园管理的由来以及现状，结合最新的网络科技发展趋势给出在网络环境下学校管理的模式，力图解决两个问题：1．网络环境对校园管理是否有益?2．如何在网络环境下进行校园管理?通过分析已有的网络校园管理的例子，结合实践经验，本给出了一个比较完整的网络环境下的学校管理框架，并通过实践实现了一部分功能。本还提出了对网络环境下学校管理的反思与展望。     

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

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.     

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

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.     

一个适用的远距离低压送电方案

介绍和讨论一个采用电力稳压器远距离低压送电的适用方案。     

混合药膜包膜系统释放动力学研究

存储混合型是目前研究较多的控制释放体系 ,但由于其机理较为复杂 ,目前尚未建立合理实用的动力学模型 .以混合药膜包膜体系为研究对象 ,建立了释放动力学的简化模型并获得了解析解 .实验数据表明 ,该模型适用于描述药物装填量大于饱和溶解度的药物释放动力学行为 (相对偏差小于 3 % ) .根据该模型还从理论上分析了两种限定条件 (Dm Df和 Dm Df)下药物的释放特征 :当 Dm Df时 ,释放速率变为常数 ,达到零级释放 ,其释放速率与药膜无关 ,这为零级释放缓释体系如何控制释放速率和药物释放量提供了理论依据 :当 Dm Df时 ,药物的释放速率与药膜中的释放系数、溶解度和药物的装填量有关 ,与包膜过程无关 ,其释放过程类似于混合药膜缓释体系