生物学教学设计中的任务分析

任务分析是使生物课堂教学设计走向科学化、系统化和正规化的一项重要的教学理论与技术。生物课堂教学任务分析包括：确定学生的起点能力;分析使能目标及其学习类型;分析学习的支持性条件。就任务分析的教学理论和技术,如何应用于中学生物课堂教学设计的实践,做了初步的尝试和探讨。     

主要任务

构建具有中国特色的继续教育(指职后的学历和非学历教育)体系,是实现党的十六大提出的教育奋斗目标的一个关键性工程。在邓小平关怀下诞生的广播电视大学,经过20多年的风雨历程,探索和实践了一条“费省效宏”、适应中国国情的远程继续教育道路。今后如何进一步建设和完善中国特色远程继续教育体系,是电大同仁们仍在积极不懈地思考和努力实践的课题。     

Comparison of various procedures for progressive collapse analysis of cable-stayed bridges

Alternate path(AP) method is the most widely used method for the progressive collapse analysis,and its application in frame structures has been well proved.However,the application of AP method for other structures,especially for cable-stayed structures,should be further developed.The four analytical procedures,i.e.,linear static,nonlinear static,linear dynamic,and nonlinear dynamic were firstly improved by taking into account the initial state.Then a cable-stayed structure was studied using the four improved methods.Furthermore,the losses of both one cable and two cables were discussed.The results show that for static and dynamic analyses of the cable-stayed bridges,there is large difference between the results obtained from simulations starting with either a deformed or a nondeformed configuration at the time of cable loss.The static results are conservative in the vicinity of the ruptured cable,but the dynamic effect of the cable loss in the area farther away from the loss-cable cannot be considered.Moreover,the dynamic amplification factor of 2.0 is found to be a good estimate for static analysis procedures,since linear static and linear dynamic procedures yield approximately the same maximum vertical deflection.The results of the comprehensive evaluation of the cable failure show that the tread of the progressive failure of the cable-stayed bridges decreases when the location of the failed cables is closer to the pylon.     

任务型语言教学模式下任务的分析和设计

任务型教学是20世纪80年代兴起的一种强调“做中学”的语言教学模式。而其中的“做”指的就是“完成任务的过程”。那么到底什么是任务呢？是“传统教学法”中的语言练习吗？“任务”又和哪些因素息息相关呢？教师又应该怎样来设计这个所谓的“任务”呢？其实“任务”就是“做事情”,而这些事情可以说就是日常生活中所做事情的翻版。但是值得强调的是：这种任务指的是用“目的语”来做事情,在做事情当中习得语言,所以“任务”强调的是语言的意义,而不是语言的形式。     

Freedom of Choice,Task Performance,and Task Persistence

Much current educational literature argues that providing the learner more freedom in the learning situation enhances the learning process. This experiment tested two relevant hypotheses: (1) Ss who freely choose a task will perform better at that task than Ss who are forced to do it; and (2) Ss who freely choose a task will persist longer at that task than those who are forced to do it. The experiment employed a yoked-8 design in which the first S chose to perform any of five tasks, while the second S was forced to perform that same task. The results supported only the second hypothesis. A suggested explanation of the effects of freedom of choice as a psychological variable was presented.     

新闻出版工作者的历史使命

江泽民“三个代表”重要思想对新闻出版工作有着重要的指导意义。新闻出版工作者应在全面贯彻“三个代表”精神的过程中 ,努力把握“代表中国先进文化的前进方向”的内涵和精神实质 ,做中国先进文化的建设者和传播者     

面向任务优先级和Deadline约束的网格QoS任务调度算法研究

基于网格QoS的属性分析,对单一性能评价任务调度算法进行了改进。改进后的基于QoS的网格任务调度算法在make span以及任务接受率等的综合性能上较传统的调度算法具有较大优越性。     

基于任务属性的MapReduce任务调度算法改进

针对MapReduce任务调度中任务属性取默认值的不合理性以及人为指定值的不确定性,对调度算法实现动态调整任务优先级、计算合理的Reduce任务数、明确Reduce任务启动时机等改进,达到提升任务并行度、缩短作业执行时间的目的.Fair与LATE算法改进前后的实验结果表明,基于任务属性的改进能提高调度算法性能与作业整体执行效率.