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1.
液滴撞击固体壁面现象常见于动力机械、喷雾冷却和薄膜材料沉积制备等工业生产中。将石墨烯和碳纳米管作为分散颗粒,应用超声波分散技术制备均匀性与稳定性良好的树脂基纳米流体。利用高速摄像技术,研究纳米流体液滴撞击固体壁面的动力学行为。基于有限元法,通过修正的幂律黏度模型耦合纳米流体的剪切变稀特性,采用水平集方法捕捉相界面的移动,建立纳米流体液滴撞击固体壁面的数值模型。模拟结果与实验结果较好一致,验证了数值模型的正确性与准确性。研究发现实验配制的纳米流体表现出非牛顿剪切变稀特性,纳米颗粒的加入抑制了液滴撞击固体壁面过程中的铺展和回缩行为。随着幂律指数m的减小,液滴撞击固体壁面后的铺展范围变大。随着表面张力的增大,液滴的无量纲直径在铺展阶段无明显变化,但在回缩阶段逐渐减小。 相似文献
2.
新媒体时代为科技期刊的出版带来了新的机遇和挑战。通过对传统科技期刊出版流程的研究发现,在编辑、校对流程中普遍存在“数字化断层”现象。该现象导致了稿件库存现象严重以及数字出版周期过长、效率过低、质量不高。新媒体时代,期刊论文只有在数字出版后才能被有效传播、检索、发现和有效引用。解决期刊出版的“数字化断层”问题,可以有效缩短发表周期,最终提升期刊的整体影响力。最后针对优化编辑流程、专设网络编辑、重视优先数字出版、共享出版平台等方面提出一些应对措施。作者自主开发了数字出版加工平台,可在高校期刊共享使用。 相似文献
3.
Lucy Spowart Jennie Winter Rebecca Turner Penny Burden Kathryn Ann Botham Reema Muneer 《高等教育研究与发展》2019,38(6):1299-1312
ABSTRACTWith increasing moves globally towards the professionalisation of teaching in Higher Education, there is growing interest in the role of accredited professional recognition schemes that provide professional development for established university teaching staff. In the UK, There are now over 120 professional recognition schemes, resulting in institutionally focused evaluation studies examining their impact. This article contributes to this emerging body of work; it draws on cross-institutional data and Foucauldian theorising to address two important questions. In what ways does engagement with an institutional professional recognition scheme impact on participants’ teaching development, and how does institutional culture influence that engagement? The data illustrate that whilst institutional culture drives engagement, it did little to promote teaching development. Across the case-study institutions, neo-liberalism agendas were apparent. Some staff felt pushed to achieve professional recognition in response to the increasing use of metrics to measure the student experience and to inform institutional standing in league tables. Whilst evidence shows the process of seeking accreditation can lead to an enhancement in teaching practices, caution must be taken to ensure that the professional development opportunities offered by accreditation schemes are fully realised. 相似文献
4.
Altmetrics have been proposed as a way to assess the societal impact of research. Although altmetrics are already in use as impact or attention metrics in different contexts, it is still not clear whether they really capture or reflect societal impact. This study is based on altmetrics, citation counts, research output and case study data from the UK Research Excellence Framework (REF), and peers’ REF assessments of research output and societal impact. We investigated the convergent validity of altmetrics by using two REF datasets: publications submitted as research output (PRO) to the REF and publications referenced in case studies (PCS). Case studies, which are intended to demonstrate societal impact, should cite the most relevant research papers. We used the MHq’ indicator for assessing impact – an indicator which has been introduced for count data with many zeros. The results of the first part of the analysis show that news media as well as mentions on Facebook, in blogs, in Wikipedia, and in policy-related documents have higher MHq’ values for PCS than for PRO. Thus, the altmetric indicators seem to have convergent validity for these data. In the second part of the analysis, altmetrics have been correlated with REF reviewers’ average scores on PCS. The negative or close to zero correlations question the convergent validity of altmetrics in that context. We suggest that they may capture a different aspect of societal impact (which can be called unknown attention) to that seen by reviewers (who are interested in the causal link between research and action in society). 相似文献
5.
随着互联网+教育的不断发展,混合式线上线下教育方式不断深入高校课堂,为高校教学提供了一种新的教学模式。通过教学实践,发现应用这样的教学模式,能有效进行课堂组织和丰富教学手段,但教学效果方面并没有多大提升。为此,通过前期教学实践,进一步对高校混合式教学质量影响因素进行分析,然后分别从教师意识、学生参与度、教学措施、教学内容分配及综合评价指标等方面提出解决对策,以此达到提高高校混合式教学质量的目的。 相似文献
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基础研究是原始创新的源泉,加强基础研究,前瞻未来科学发展方向,抢占未来发展的制高点,是新时代国家对中国科学院学部发挥学术引领作用的新要求。中国科学院学部学科发展战略研究工作旨在探索各学科内在发展规律,前瞻各学科中长期发展趋势,把握新兴和交叉学科发展方向,明确科学前沿和重大科学问题,指导我国相关学科发展。文章介绍了中国科学院学部学科发展战略研究工作的基本情况,并通过文献调研和问卷调查分析了学科发展战略研究工作的实施效果与影响。研究表明,中国科学院学部学科发展战略研究工作产生了较好的社会影响、政策影响和学术影响,在夯实我国学科基础、优化科技布局、促进人才培养、增进学术交流、推动科技创新和建设创新型国家等方面均作出了积极贡献。 相似文献
8.
[目的/意义]社交问答用户的社会资本受多种因素影响,本文旨在探究社交问答用户不同的健康信息行为对其社会资本积累的影响。[方法/过程]以知乎网上糖尿病话题下2 537个问题帖子,3 567个回答的1 650名用户为研究对象,依据L.Nan的社会资本理论和N.Uphoff对社会资本的分类,将社交问答用户的社会资本分为认知性和结构性两类,用多元线性回归的方法分析社会问答用户的健康信息行为与社会资本之间的关系。[结果/结论]用户的健康知识贡献行为和自我信息披露行为在不同程度上正向促进社会资本的累积,而不同的健康知识获取行为对认知性社会资本和结构性社会资本的影响有差异。这些结果有助于社交问答用户提高社会资本,平台完善用户服务和激励机制。 相似文献
9.
随着"双一流"建设总体方案的提出,科研成果越来越受到重视,高校图书馆开展学科评价服务,对于提升图书馆的服务和地位具有至关重要的意义。本文在分析了吉林大学2010-2016年发表的论文总体情况的基础上,选取论文发表总量前10名的学科为研究对象,运用文献计量学方法和马尔可夫模型分析方法,与传统的评价指标相结合,构建相应的综合评价指标,消除学科间的基础差异,分析得出各个学科的发展速度和发展趋势情况。 相似文献
10.
《Journal of Informetrics》2019,13(2):485-499
With the growing number of published scientific papers world-wide, the need to evaluation and quality assessment methods for research papers is increasing. Scientific fields such as scientometrics, informetrics, and bibliometrics establish quantified analysis methods and measurements for evaluating scientific papers. In this area, an important problem is to predict the future influence of a published paper. Particularly, early discrimination between influential papers and insignificant papers may find important applications. In this regard, one of the most important metrics is the number of citations to the paper, since this metric is widely utilized in the evaluation of scientific publications and moreover, it serves as the basis for many other metrics such as h-index. In this paper, we propose a novel method for predicting long-term citations of a paper based on the number of its citations in the first few years after publication. In order to train a citation count prediction model, we employed artificial neural network which is a powerful machine learning tool with recently growing applications in many domains including image and text processing. The empirical experiments show that our proposed method outperforms state-of-the-art methods with respect to the prediction accuracy in both yearly and total prediction of the number of citations. 相似文献