IPv4／IPv6的共存与过渡

因特网正面临从传统1Pv4到IPv6的转变以及一段时期的共存。本文是一个技术人员结合IETF的工作对IP和IP网络的发展道路的看法。     

Teacher educators working on their own professional development: goals,activities and outcomes of a project for the professional development of teacher educators

This article reports on the professional development of teacher educators within the context of a national project, ‘Professional Quality of Teacher Educators,’ where a professional standard and a standards‐based procedure of (self‐)assessment and professional development have been created and effectively implemented. This project offered a unique opportunity to analyze the goals, activities and outcomes of the process of professional development of teacher educators in a situation in which this development is promoted by the professional group as a whole. In our research, we used 25 completed portfolio's made by teacher educators participating in the standards‐based procedure of (self‐)assessment and professional development. We found that teacher educators, participating in this procedure, prefer the development of their knowledge and skills over the development of their attitudes and beliefs. For their professional development, the teacher educators experiment with new activities within the work‐situation and interact with colleagues within their professional community, more than that they study theory or reflect on their work. The participating teacher educators experience a positive impact at the personal level (change in cognition and behavior). More than one‐third of them share outcomes with others. Above, they report a more positive self‐esteem and more enthusiasm for teacher education. This article may motivate other countries or institutions to invest in the professional development of teacher educators. Further research is necessary on the essence of the professional qualities of teacher educators and the relation of their professional development with student learning.     

Interdisciplinary Perspectives Inspiring a New Generation of Cognitive Load Research

This special issue consists of six theoretical papers and an introduction. Each paper describes a current advance to the applications and focus of cognitive load theory (CLT). Four of the papers use an interdisciplinary approach outside of educational psychology by combining CLT with elements of evolutionary biology, mirror neuron research, cognitive brain science, and the philosophy of science. The remaining two papers use an intradisciplinary approach within educational psychology by applying CLT to self-regulation and heuristic learning. This paper introduces CLT, overviews each contribution, and summarizes the main themes.     

Developing Biology Lessons Aimed at Teaching for Understanding: A Domain-specific Heuristic for Student Teachers

Teaching for understanding requires teachers to organize thought-demanding activities which continually challenge students to apply and extend their prior knowledge. Research shows that student teachers often are unable to develop lessons in teaching for understanding. We explored how a domain-specific heuristic can assist student biology teachers in developing problem-posing lessons according to teaching for understanding. Worksheets of lesson plans were analyzed according to criteria for problem-posing lessons. Furthermore, student teachers’ perceptions of the design heuristic’s usefulness were categorized in a cyclical process. In general, the heuristic appeared helpful to most student teachers for designing problem-posing lessons satisfactory according to the criteria. Furthermore, teachers indicated that using the heuristic deepened their subject matter knowledge and their awareness of pupils’ prior knowledge.     

Using Electroencephalography to Measure Cognitive Load

Application of physiological methods, in particular electroencephalography (EEG), offers new and promising approaches to educational psychology research. EEG is identified as a physiological index that can serve as an online, continuous measure of cognitive load detecting subtle fluctuations in instantaneous load, which can help explain effects of instructional interventions when measures of overall cognitive load fail to reflect such differences in cognitive processing. This paper presents a review of seminal literature on the use of continuous EEG to measure cognitive load and describes two case studies on learning from hypertext and multimedia that employed EEG methodology to collect and analyze cognitive load data.     

Facilitating teachers' professional growth through their involvement in creating context-based materials in science

This paper traces the professional growth of science teachers in Trinidad and Tobago through their involvement in the production of context-based resource materials relevant to the lives of their students during workshop sessions. Grounded theory methods were used to analyse pre- and post-workshop questionnaire responses, tape-recorded group discussions and several draft lesson outlines. The findings show that professional growth is indicated by changes in the nature of the contexts chosen as lesson foci, the role of these contexts in the overall lesson design, and teachers' perceptions of contextualised teaching. Conflicts between students' cultural and scientific understandings were not addressed by these teachers.