应用面向对象技术取代全局变量的研究与实现

面向对象技术的封装性与全局变量的使用构成了一对不可调和、严重的矛盾。章以此为出发点，研究了在面向对象编程环境下大量使用全局变量的危害性，剖析了静态成员的访问机制，论证了用静态成员变量取代全局变量的可行性，同时给出了具体的实现方法。     

Director环境下面向对象的英语课件开发初探

当前,高校学生利用与英语教材配套发行的教学辅助光盘(英语课件)进行自主学习已成为英语教学中一个重要的环节。本文通过比较现有一些大学英语课件的开发过程,分析其在开发过程存在问题。针对存在问题,作者依托已经出版发行的《大学英语(第三版)》的开发过程,对在Director环境下面向对象的程序设计与实现进行了探讨,以期为同类课程课件的开发和应用提供借鉴和思路。     

UML在面向对象需求分析中的应用*

对UML在面向对象需求分析中的应用进行了探讨，指出以用例为核心组织需求，是一种行之有效的需求分析方法。并结合实例，重点分析讨论了建立用例模型的几个关键性问题。     

A structured model of the dynamics of student learning in developing countries,with applications to policy

Learning trajectories vary amazingly widely across countries, regions, and individual students in dynamic ways. In this paper we develop a parametrized structural model of the dynamics of the learning process and use the model for suggestive policy applications. We first synthesize the existing empirical literature on learning profiles, which suggest a clear set of parameters that formally characterize the learning process. We then calibrate this model of the learning process to reproduce the distribution of observed learning outcomes in low- and middle-income countries. Applying our calibrated model to policy simulations, we find that expanding schooling to universal attainment of basic education without changing the dynamics of the learning process would produce very little additional learning. Adjusting other parameters in the model, however, has large, positive effects. Slowing the pace of curriculum, so that more children can keep up, increases average learning in grade 10 by the learning equivalent of 1.6 years of schooling. Expanding the student skill levels that learn from a given level of instruction to account for within classroom heterogeneity of learning levels increases average grade 10 learning by the equivalent of a full year of schooling. The parameters we use are flexible, to accommodate the learning process in different contexts, and future work could explore additional parameterizations and calibrations for informing plans to improve education systems’ coherence for learning.     

面向对象技术在CAI课件开发中的应用

将软件工程原理中的瀑布模型应用于课件开发．运用面向对象软件工程原理进行需求分析和设计，使CAI课件最大限度地满足实际教学需要。     

Should students design or interact with models? Using the Bifocal Modelling Framework to investigate model construction in high school science

The Bifocal Modelling Framework (BMF) is an approach for science learning which links students’ physical experimentation with computer modelling in real time, focusing on the comparison of the two media. In this paper, we explore how a Bifocal Modelling implementation supported learning outcomes related to both content and metamodeling knowledge, focusing on the role of designing models. Our study consisted of three conditions implemented with a total of 69 9th grade high-school students. The first and second classes were assigned two implementation modes of BMF: with and without a model design module. The third condition, employed as a control, consisted of a class that received instruction in the school’s traditional approach. Our results indicate that students participating in both BMF implementations demonstrated improved content knowledge and a better understanding of metamodeling. However, only the ‘BMF-with-design’ group improved significantly in both content and metamodeling knowledge. Our qualitative analyses indicate that both BMF groups designed detailed models that included scientific explanations. However only students who engaged in the model design component: (1) completed a detailed model displaying molecular interaction; and (2) developed a critical perspective about models. We discuss the implications of those results for teaching scientific science concepts and metamodeling knowledge.     

大同御河兴云桥的历史及建筑形制

御河是大同市内最主要的一条河流,它由北而南从城东门外流过。作为东出必经之路,御河桥上建置桥梁有着悠久的历史。目前,根据考古出土文物及参考文献可以得知,御河上建桥有确切记载始于金代,它是一座五拱石桥,元代重修时命名"兴云桥"。金代御河桥经元明二代历时四百余年,万历八年拓故基重建为十九孔石拱桥,仍名兴云桥,清嘉庆年间倾圯。     

Knowledge is power: Issues of measuring training and performance in cycling

ABSTRACT

Mobile power meters provide a valid means of measuring cyclists’ power output in the field. These field measurements can be performed with very good accuracy and reliability making the power meter a useful tool for monitoring and evaluating training and race demands. This review presents power meter data from a Grand Tour cyclist’s training and racing and explores the inherent complications created by its stochastic nature. Simple summary methods cannot reflect a session’s variable distribution of power output or indicate its likely metabolic stress. Binning power output data, into training zones for example, provides information on the detail but not the length of efforts within a session. An alternative approach is to track changes in cyclists’ modelled training and racing performances. Both critical power and record power profiles have been used for monitoring training-induced changes in this manner. Due to the inadequacy of current methods, the review highlights the need for new methods to be established which quantify the effects of training loads and models their implications for performance.     

世界花样游泳集体自由自选造型变化趋势

为了探索世界花样游泳造型变化的趋势,对2007年十二届世锦赛,2006年第六届世界杯,2005年十一届世锦赛和2004年第28届奥运会花样游泳比赛集体自由自选前六名队伍的造型变化进行统计分析。结果显示：造型数量增加,变化速度加快,密度难度加大;托举的类型增加、层次增多,出水的人数增多,出水位置高,成型时间短,动作惊险、多变。中国队托举与立体造型进步明显,而密集编队、盲点编队、倒立移动编队等体现编队难度的指标与世界前三名队伍相比有一定的差距。     

基于UML的高校排课系统的分析与设计

运用基于UML的面向对象分析方法,借助于统一建模语言,使用Rational Rose为建模工具,对高校排课系统进行建模设计,利用表示系统静态特征的UML类图、用例图和描述系统动态行为特征的时序图对其进行了详细描述。