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981.
982.
1937年7月,抗日战争全面爆发初期,面对空前严重的民族危机,中国知识界开始探讨中国文化的发展方向,掀起了关于文化问题的反思和讨论.知识界关于文化问题的讨论,不仅有力地促进了抗战文化运动的兴起和发展,而且为中国共产党新民主主义文化理论的形成奠定了一定的基础. 相似文献
983.
984.
湖南旅游教育事业的发展应立足湖南,面向全国,放眼世界,以市场为导向,走校企合作,校际联合,深化旅游教育领域改革的道路,不断提高旅游师资队伍的素质,加强旅游专业建设。 相似文献
985.
某热轧带钢厂Cr3材质锻钢平整工作辊每次上机服役仅生产1000t钢卷即需换辊修磨,严重影响产品质量和轧辊使用寿命。对Cr3材质锻钢工作辊进行硬度、金相组织等检验发现,虽然辊面金相组织正常,但是硬度偏低,导致在使用过程中出现塑性变形,表明这种材质的工作辊不适合在“干”平整的工况条件下用作热轧平整工作辊。建议采用具有更高耐磨性、更高热稳定性的高速工具钢、半高速工具钢和改进型高NiCr无限冷硬铸铁工作辊等材质工作辊代替Cr3材质锻钢工作辊,以提高生产效率和轧辊寿命。 相似文献
986.
李玉昆 《黎明职业大学学报》2007,(1):14-17
泉州安平商人因其所在地理条件的优越,唐代就已远出经商。安平商人既从事国内贸易,又从事海外贸易,行商区域遍及祖国大江南北、海外各地。安平商人经商特点有:以农为本,农贾兼业;贾儒兼营,从儒入贾。文化精神体现为善用智力经商,临财有信、拾金不昧,勤俭节约、乐善好施等。 相似文献
987.
在场致发射器件中 ,发射电流通常会随着工作时间的增加而跌落 .发射电流跌落的机理较为复杂 .本文模拟分析了一次电子从场致发射发射体表面的发射情况 .根据一次电子的电流密度分布和运动轨迹 ,研究残余气体分子的电离 .然后计算正离子在电场中的运动轨迹 ,利用半经验模型分析不同能量的正离子对发射体表面的损伤情况 ,最后估计出在不同残余气压和一次电流下发射电流的衰减 相似文献
988.
The main purpose of this paper is to investigate the intellectual structure of the research on educational technology in science education (ETiSE) within the most recent years (2008–2013). Based on the criteria for educational technology research and the citation threshold for educational co-citation analysis, a total of 137 relevant ETiSE papers were identified from the International Journal of Science Education, the Journal of Research in Science Teaching, Science Education, and the Journal of Science Education and Technology. Then, a series of methodologies were performed to analyze all 137 source documents, including document co-citation analysis, social network analysis, and exploratory factor analysis. As a result, 454 co-citation ties were obtained and then graphically visualized with an undirected network, presenting a global structure of the current ETiSE research network. In addition, four major underlying intellectual subfields within the main component of the ETiSE network were extracted and named as: (1) technology-enhanced science inquiry, (2) simulation and visualization for understanding, (3) technology-enhanced chemistry learning, and (4) game-based science learning. The most influential co-citation pairs and cross-boundary phenomena were then analyzed and visualized in a co-citation network. This is the very first attempt to illuminate the core ideas underlying ETiSE research by integrating the co-citation method, factor analysis, and the networking visualization technique. The findings of this study provide a platform for scholarly discussion of the dissemination and research trends within the current ETiSE literature. 相似文献
989.
Konstantinos Stouraitis Despina Potari Jeppe Skott 《Educational Studies in Mathematics》2017,95(2):203-217
The study reported in this paper concerns the tensions and conflicts that teachers experience while they enact a new set of reform-oriented curricular materials into their classrooms. Our focus is οn the interactions developed in two groups of teachers in two schools for a period of a school year. We use Activity Theory to study emerging contradictions and we elaborate on the construct of dialectical opposition to understand the nature of these contradictions and their potential for teacher learning. We provide evidence that discussions about contradictions and their dialectical character in the two groups support teachers to engage differently in mathematics teaching and learning and carry potentials for shifts in the practices that evolve in their classrooms. Our study addresses empirically in the context of mathematics teaching the philosophical claim about the role of contradictions as a driving force for any dynamic system. 相似文献
990.
Jeroen Lavrijsen Ides Nicaise 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》2017,63(2):257-280
An important issue in the design of secondary-level education is the balance between conveying general and occupation-specific (vocational) skills. On the one hand, vocationally oriented programmes, providing occupation-specific skills with immediate labour market relevance, have repeatedly been shown to secure safe pathways into employment. On the other hand, these programmes tend to put less emphasis on developing general knowledge, skills and competencies, including numeracy and literacy, which are foundational to lifelong learning. Hence, when the needs of the labour market change, employees who opted for a vocational track when they were at secondary school risk being less flexible in adapting to such changes later in their career. The authors of this article examine whether this results in a trade-off between short-term gains and long-term losses by considering differences in the labour market careers of vocationally and generally educated respondents in the 2012 Programme for the International Assessment of Adult Competencies (PIAAC). Their results suggest that early labour market benefits of vocational specialisation decrease over time; the authors relate this to its lower ability to equip secondary school students – future employees – with skills for lifelong learning. 相似文献