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91.
In recent years there has been widespread interest in the implementation of information and communication technologies (ICT) in schools. While most studies primarily focus on the use of ICT in teaching and learning, little attention has been given to their incorporation as a professional tool outside the classroom. Using a digital inequality approach, the aim of this paper is to develop and test a model of the factors that affect teachers' professional use of ICT, particularly the Internet, in primary and secondary schools. One thousand four hundred and five (1405) teachers from a representative sample of 536 primary and 273 secondary schools in Spain were surveyed. The dependent variables include attitudes towards the professional use of ICT and the use of the Internet in professional practice. The explanatory variables are the socio-demographics, school-level information, frequency of Internet access within and outside the school, educational ICT training, digital literacy, and organisational development. Controlling for socio-demographics and school-level information, multiple regression analyses are used to make inferential judgements and test the separate effects of the independent variables. Findings suggest that technological factors and organisational practices are important predictors of ICT appropriation for professional purposes.  相似文献   
92.
The ‘will, skill, tool’ model is a well-established theoretical framework that elucidates the conditions under which teachers are most likely to employ information and communication technologies (ICT) in the classroom. Past studies have shown that these three factors explain a very high degree of variance in the frequency of classroom ICT use. The present study replicates past findings using a different set of measures and hones in on possible subfactors. Furthermore, the study examines teacher affiliation for constructivist-style teaching, which is often considered to facilitate the pedagogical use of digital media. The study’s survey of 357 Swiss secondary school teachers reveals significant positive correlations between will, skill, and tool variables and the combined frequency and diversity of technology use in teaching. A multiple linear regression model was used to identify relevant subfactors. Five factors account for a total of 60% of the explained variance in the intensity of classroom ICT use. Computer and Internet applications are more often used by teachers in the classroom when: (1) teachers consider themselves to be more competent in using ICT for teaching; (2) more computers are readily available; (3) the teacher is a form teacher and responsible for the class; (4) the teacher is more convinced that computers improve student learning; and (5) the teacher more often employs constructivist forms of teaching and learning. The impact of constructivist teaching was small, however.  相似文献   
93.
This study investigated the impact of different modes of scaffolding on students who are learning science through a web-based collaborative inquiry project in authentic classroom settings and explored the interaction effects with students’ characteristics. The intervention study aimed to improve domain-specific knowledge and metacognitive awareness during online information problem solving (IPS) as part of an online inquiry project. Three experimental conditions (teacher-enhanced scaffolding, technology-enhanced scaffolding, and both forms of scaffolding) were compared with a control condition in a two-by-two factorial quasi-experimental design. Moreover, gender and prior knowledge were examined as two factors which may have a significant impact on Web-based learning. In a four-week field study in secondary science education, pretest-posttest differences were measured. In total 347 students from 18 secondary school classes were involved and the classes were randomly distributed over the 4 conditions. Our findings support the notion of multiple scaffolding as an approach to enhance both knowledge acquisition and metacognitive awareness with respect to IPS-processes and to meet a mix of students with different needs within the context of a web-based inquiry learning project.  相似文献   
94.
Adolescents spend a substantial part of their leisure time with playing games and using social media such as Facebook. The present paper examines the link between adolescents' computer and Internet activities and computer literacy (defined as the ability to work with a computer efficiently). A cross-sectional study with N = 200 adolescents, aged 17 on average, was conducted. Hierarchical regression analyses showed that an increase in time spent playing games on a PC/Mac was related to higher scores on practical and theoretical computer knowledge. Moreover, practical computer knowledge was higher for adolescents who liked playing shooters, fantasy games, or Facebook-games. Frequency of social media use was associated with higher scores in practical computer knowledge. A bootstrap analysis indicated that this relationship was mediated by a decrease in computer anxiety, not by more positive attitudes toward the computer. Gender yielded substantial main effects on the media literacy variables but the associations between the computer and Internet activities and the literacy aspects were similar for boys and girls. This study is expected to encourage future longitudinal research on adolescents' incidental learning during leisure time computer and Internet activities.  相似文献   
95.
分析现代职教体系与产业结构调整的关系,提出必须将培养更大规模和更高质量的技能型人才、高端技能型人才作为建立现代高职教育体系,促进职业教育发展的战略重点。要在现代职业教育体系下,根据地方现代化建设的要求,通过建立现代职业教育体系为经济社会发展做好人才和智力支撑。重点论述了现代职教体系中中高职的有机衔接。提出了以构建现代职业教育体系为核心,深入推进职业教育发展的几个主要措施。  相似文献   
96.
介绍利用第三方开发软件Inno Setup制作基于VisualLISP二次开发程序的自动安装处理程序。分析了AutoCAD注册表结构,确定出需在注册表中注册的应用系统变量。通过详细分析Inno Setup的脚本,定制出在AutoCAD下使用VisualLISP二次开发安装程序的脚本文件。为使用VisualLISP二次开发的用户提供了一种实用的安装程序制作方法。  相似文献   
97.
潜江凹陷潜江组页岩储层以次生孔隙为主,总体属于中孔-低渗或低孔-低渗性储层;潜江凹陷潜江组页岩在成岩作用、生烃过程中发育形成了较为有利的裂缝、(裂缝)-溶蚀孔隙及次生晶间和粒间孔隙,构成潜江凹陷潜江组页岩储层的主要油气储集空间。  相似文献   
98.
随着信息化步伐的加快,企业对生产数据归档的要求越来越高,利用传统方式实现WinCC数据归档已不能满足生产需要。通过对现有WinCC软件的OPC接口分析,提出了采用开发效率高的VB软件和数据存储功能强大的SQL软件对WinCC进行二次开发的可行方案。该方案实现了对WinCC过程数据的高级归档,满足企业对数据归档的要求,同时避免了使用西门子专用归档选件带来的高成本开发。目前,该方案已在工程应用中取得了较好效果,具有一定的应用推广价值。  相似文献   
99.
仲丁醇含量对正丁烯直接水合法制仲丁醇的影响   总被引:1,自引:0,他引:1  
曾岳飞 《辽宁化工》2004,33(3):164-166
研究了正丁烯直接水合法制仲丁醇工艺中原料水中仲丁醇含量对反应的影响.当原料水中含有少量仲丁醇时(约0.9%时),其对水合反应过程的转化率影响不大;原料水中含有少量仲丁醇时,反应过程的稳定性比较好.当水合反应的原料水中仲丁醇浓度增大时(原料水中仲丁醇浓度为2.0%左右时),反应过程的转化率明显下降.当水合反应的原料水中仲丁醇含量进一步增大时,反应过程的转化率下降明显,但呈非线性变化.  相似文献   
100.
Tingting Sun  Linxi Zhang 《Polymer》2004,45(22):7759-7766
We present a new model considering the effects of secondary structure on the conformations and folding process of protein-like chains in three-dimensional simple cubic lattice in this paper. The properties such as chain dimensions, shape, average contacts and chain average energy with different helical energy of a helix (εhel=0, −0.75, −1.5, and −3 in the unit of kT) are discussed here. Unlike conventional polymers, protein-like chains are much compact. We also find that the ability to form helix of residue is different under the condition of different helical energy of a helix. The energy distribution for protein-like chains with different length and the conformation changes in the process of folding of proteins are discussed. Comparisons with real protein chains are also made.  相似文献   
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