高中化学新课程课堂教学评价

传统化学课堂教学评价重结果轻过程,重知识技能轻情感、态度与价值观发展,评价形式、评价内容、评价主体单一,教师、学生处于被动地位,它已经无法适应和满足新课程的要求.高中化学新课程课堂教学评价应重视发展、重视过程、重视评价多元化.综合运用多元化的评价方式,充分运用灵活多样的评价方法,以提升教学的有效性,促进学生全面发展和推进教育教学的与时俱进.     

Classroom action research on formative assessment in a context-based chemistry course

Context-based science courses stimulate students to reconstruct the information presented by connecting to their prior knowledge and experiences. However, students need support. Formative assessments inform both teacher and students about students’ knowledge deficiencies and misconceptions and how students can be supported. Research on formative assessments suggests a positive impact on students’ science achievement, although its success depends on how the formative assessment is implemented in class. The aim of this study was to provide insights into the effects of formative assessments on achievement during a context-based chemistry course on lactic acid. In a classroom action research setting, a pre-test/post-test control group design with switching replications was applied. Student achievement was measured in two pre-tests, two post-tests and a retention test. Participants were Grade 9 students from one secondary school in the Netherlands. Repeated-measures analysis showed a significant effect of formative assessments on students’ achievement. During the implementation of the formative assessments, intriguing discussions emerged between students, between students and teacher, and between teachers. Adding formative assessments to context-based approaches reinforces their strength to meet with the current challenges of chemistry education. Formative assessments affect students’ achievement positively and stimulate feedback between students and teacher(s).     

无线传感器网络节点的物理层设计

比较和分析了无线传感器网络节点物理层设计的各种无线通信技术、现有的成熟标准、重要的射频参数以及不同的处理器方案,对节点物理层设计的各个主要方面进行了较为全面的研究.介绍了无线传感器网络节点的一种实现,给出了相关的测试数据以及一种“单处理器双工作频率”的新节能策略.分析了符合传感器网络MAC算法中节点周期性侦听要求的节点寿命估算问题.指出无线传感器网络节点物理层设计的关键考虑因素为:RF启动时间(决定MAC协议可以实现的最佳节点睡眠时间比例和最小的退避时间颗粒)、RF载波频率和调制方式(决定射频收发功耗)以及处理器工作在2个频率的片上系统的总体功耗.     

最优二叉树在通信编码中的应用

字符出现的频率不同,在传输中采用非等长二进制编码传输会提高传输效率,在字符的出现频率已知前提下,采用最优二又正则树算法,可以得到最佳前缀码.     

中学历史教学现状的调查及对高师教法课的思考

高师教法课应从教育理念、教学内容、教学手段等方面加以改进,以适应基础教育改革发展的需要。     

对网络时代统计工作的思考

先进的计算机和网络技术赋予了统计信息不同于传统模式的种种特征.在信息化时代,统计作为一项始终与信息打交道的社会实践活动,在国民经济中发挥着越来越重要的作用,而提高统计信息质量则是其中的关键问题.     

对我国高等职业教育教学模式的探讨

本文通过对高等职业教育的目的和特点分析，找出现有教育模式的不足，同时结合国外职业教育的成功经验与我国的实际状况，给出一可行的职业教育模式，以期解决现有职业教育存在的问题。     

朗读中语调偏误的类型分析

朗读的语调是语流中呈现出来的音高变化的总体模式,它与字调、轻重、停连、快慢等因素有关。从字调偏误、轻重音失当、语句高低升降的“失势”、停连的“失态”、语速快慢的“失度”等方面入手对语调偏误的类型进行剖析,将有利于朗读实践。     

The inadequacy of individual educational program (IEP) goals for high school students with word-level reading difficulties

This investigation analyzed goals from the Individual Educational Programs (IEPs) of 54 high school students with diagnosed reading disabilities in basic skills (decoding and/or word identification). Results showed that for 73% of the students, the IEPs written when they were in high school failed to specify any objectives regarding their acute difficulties with basic skills. IEPs from earlier points in the students’ educations were also reviewed, as available. For 23 of the students, IEPs were present in the students’ files for three time points: elementary school (ES), middle school (MS), and high school (HS). Another 20 students from the sample of 54 had IEPs available for two time points (HS and either MS or ES). Comparisons with the IEPs from younger years showed a pattern of decline from ES to MS to HS in the percentage of IEPs that commented on or set goals pertaining to weaknesses in decoding. These findings suggest that basic skills deficits that persist into the upper grade levels are not being sufficiently targeted for remediation, and help explain why older students frequently fail to resolve their reading problems.     

1016名学生PTC尝味能力基因频率的调查

目的:了解味盲基因频率和基因型频率在不同群体中的分布,从而为人种学及人类群体遗传学提供基本数据,并用于研究某些疾病。方法:本文是运用阈值法研究满、汉、回三民族人的尝味能力,并计算了味盲者和尝味者的基因频率。结果:三民族味盲基因频率分别为:满族:0.4588.汉族:0.2845 回族:0.4431。结论:满、汉、回三民族人对PTC尝味能力在统计学上存在显著差异,不同的民族有不同的基因库。