自然资源非市场价值评估的选择实验法:原理及应用分析

选择实验作为资源环境领域非市场价值评估的重要方法之一.经过近30年的应用与发展,选择实验已经成为目前主要发达国家研究非市场价值评估和公共政策评价最主要的方法之一.但是,该方法在我国的理论研究相对较少,针对性研究与应用缺乏系统性.本文首先介绍了选择实验的原理,对选择实验诞生以来在资源环境和生态管理等领域的应用进行了综述,在举例说明国内外选择实验实践应用的基础上,提出了选择实验在我国可能的应用范围,包括生态补偿、流域管理、珍稀物种保护、自然景观的开发等方面,同时还总结了选择实验在实践应用中应注意的关键问题,旨在为我国相关理论研究与实践提供基础.     

浅议构建以学习者为中心的课程教学大纲

笔者通过对目前高校传统课程教学大纲编制及执行中存在问题的探析以及原因分析,提出借鉴美国高校的做法,构建以学习者为中心的课程教学大纲,并对构建以学习者为中心的大纲原因、以学习者为中心的大纲组成进行了较详细的论述。     

混凝土结构耐久性的影响因素及对策

钢筋混凝土结构是应用非常广泛的一种结构形式,但由于其结构自身和使用环境的特点,使得混凝土结构经常存在严重的耐久性问题。通过对国内外钢筋混凝土结构工程耐久性现状的介绍,论述影响混凝土结构耐久性的因素及混凝土的破坏机理,并针对性地提出预防的措施。     

网络课堂中非生理性别与生理性别对人际冲突的影响(英文)

本研究探讨了性别对网络课堂中学生间冲突程度的影响。研究者首先检查了文化和冲突间的关系,并且对性别和冲突间的关联做了文献分析,接着具体探索了生理和非生理性别（sex,gender）、网络学习经验（所上网络课程的多少）,和冲突在网络学习环境中的关联。虽然研究男女性别和冲突的文章有很多,但研究更深一步探求抽象性别（即gender,非生理性别）对冲突程度和态度的影响。研究中采用了专门研究性别和冲突的问卷调查工具。     

组合箱梁调平层施工质量及其裂缝控制

以新沂河大桥施工为例，分析预应力组合箱梁调平层在施工过程中产生裂缝的原因，提出在施工过程中应重视的几个工艺环节，在此基础上，还提出调平层裂缝的解决方法与质量控制措施．     

城市地铁施工预支护方案多目标多层次系统多维模糊决策

在城市地铁区间施工中,预支护方案的选择涉及诸多因素,本文基于地铁工程的特点,综合应用系统工程的模糊数学识别理论与模糊关系优选理论,建立地铁施工预支护方案选择的多目标多层次模糊决策理论模型,以方案的目标特征值作为最低层次的输入,依次以低层次的输出作为高层次的输入,对每一层次进行模糊计算,最后用级别向量的特征值对各个预支护方案进行排序,得出最优方案。通过算例计算得到比较理想的结果,有效地解决受众多模糊性和不确定性因素影响的地铁施工预支护方案的多目标优化决策问题。     

Exploring a Personal Social Knowledge Network (PSKN) to aid the observation of connectivist interaction for high- and low-performing learners in connectivist massive open online courses

This study adds a new perspective to the observations about connectivist interaction behavior in cMOOCs by extending the notion of network building from the perspective of individuals. We explore the possibility of building a learning network named Personal Social Knowledge Network (PSKN) to support in the monitoring of learning performance and interaction in cMOOCs. The sample in this study included 284 preservice teachers and their learning lasted approximately 12 weeks. Data were primarily gathered by PSKN graphs. The results revealed a correlation between connectivist interaction measured by the PSKN (including density structure) and learning performance. The results also revealed differences in connectivist interaction behavior and patterns, indicated by PSKN (densities and structures), for high- and low-performing learners in cMOOCs. The high-performing learners show deeper knowledge interaction and social communication in addition to simple knowledge sharing and social communication. Additionally, as time passed and the PSKN of high-performing learners extended further, their interaction behavior became more complex and their role had gradually changed from “learning” to “teaching” as well as from knowledge acceptance to knowledge creation in cMOOCs.     

Message design for mobile learning: Learning theories,human cognition and design principles

The demands of an increasingly knowledge‐based society and the dramatic advances in mobile phone technology are combining to spur the growth of mobile learning (mLearning). However, for mLearning to attain its full potential, it is essential to develop pedagogy and instructional design tailored to the needs of this new learning environment. At present, there is a lack of research on message design for mLearning. Towards these ends, this paper explores the principles and processes of message design for mLearning, including the influence of learning and cognitive theories, human–computer interaction principles, devices and methodologies. And it presents a number of practical guidelines for designing instructional messages for mLearning.     

基于高质量反馈源的XML查询扩展

有效避免伪反馈的"查询主题漂移"主要需要解决两大问题,一是如何确定相关文档,形成较高质量的伪相关文档集,另一个是在伪相关文档集里如何挑选扩展信息.本文主要研究在获取了高质量伪相关文档集合的基础上如何有效进行XML查询扩展.针对XML文档的特点,提出了扩展向量空间模型的查询词扩展方法.实验结果表明,与初始查询和传统的词项扩展方法相比,该扩展方法更能获得与用户查询意图相关的扩展信息,更能有效地提高检索质量和性能.     

国际学生对在线课堂学习支持的需求

此文研究了英语非母语学生,在美国某所公共大学网络课堂上学习时候所需要的帮助和支持。建立在网络教学文化差异研究的基础上,本研究关注这些学生在网络学习中可能面临的各种挑战(语言、文化、社交)等。研究揭示了这些挑战在这所大学网络课堂上的显现,并且建议了教学改进方法,比如教师应该更多地理解不同文化背景学生的学习方法和技能,从而改进教学设计和实施。