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201.
This article explores the ethos of multi-denominational primary schools in the context of increasing cultural and religious diversity in the Republic of Ireland. In particular, it investigates how the official ethos is played out in day-to-day school interactions. The mixed-methods study draws on data collected from 11 community national schools focussing on the perspectives of principals, teachers and pupils. The data indicates while schools’ formal ethos sets out guiding principles and standards, a closer look reveals the specific identity of each individual school within the broader formal framework. The article presents a new perspective on school ethos research by exploring the extent to which it guides the promotion of diversity and tolerance in a multi-faith context. While the study is carried out in Ireland, it is also of interest to other jurisdictions where schools are faced with increasing religious diversity among their student population.  相似文献   
202.
Growing recognition of the complexity of children’s lives has led to strong advocacy in education research literature for greater collaboration between researchers from different paradigms to address the ‘wicked’ problems that face contemporary children and families. There is little literature, however, exploring how collaboration works in practice. This paper, drawing on researcher reflective narrative, and using Cultural Historical Activity Theory as a heuristic framework, describes and critiques the formative stages of an educational research collaborative group of five early and one mid-career early childhood education researchers (the authors), from two universities, and with quite different epistemological and ontological understandings. It outlines, from an insider perspective, some of the outcomes, challenges and tensions associated with participating in the research group, and concludes by providing some implications for policy and considerations for those contemplating forming a collaborative group.  相似文献   
203.
Ordinary and thermal diffusion of moisture in activated alumina are investigated using a new diffusion cell design and scheme of analysis reported earlier. The specific form of the mass flux equation has a pronounced effect on the magnitude of the associated thermal diffusion ratio. In the case of activated alumina-moist air, if a partial pressure gradient is used, then the thermal diffusion term is small if not zero.Free, Knudsen and surface diffusion all play a part in the diffusion through activated alumina. However, surface diffusion makes the major contribution and for this reason the model in this case can be simplified to a two parameter surface model.The activation energy for surface diffusion is constant and is approximately equal to the mean isosteric heat of absorption. In addition, mean pore radius, turtuosity, and other physical constants are computed from the least square fit of experimental data. Furthermore, the model is theoretically consistent over the entire concentration range (0≦ CACAsat).A new fact about activated alumina (Grade F1) it that it does not transfer moisture in a nonisothermal condition so long as the partial pressures of moisture on the two sides of the pellet are the same. There appears to be no previous report of this fact in the periodical literature.  相似文献   
204.
本文用矩阵的秩这个工具考察了有限维线性系统具有二次性能指标的最优输出反馈问题,得到了一个必要条件。特殊情形下,这一条件可以演化为最优输出反馈增益与观测矩阵的乘积即为状态反馈增益这个相当清晰的关系。  相似文献   
205.
Lee K  Kim C  Young Yang J  Lee H  Ahn B  Xu L  Yoon Kang J  Oh KW 《Biomicrofluidics》2012,6(1):14114-141147
We propose a simple method for forming massive and uniform three-dimensional (3-D) cell spheroids in a multi-level structured microfluidic device by gravitational force. The concept of orienting the device vertically has allowed spheroid formation, long-term perfusion, and retrieval of the cultured spheroids by user-friendly standard pipetting. We have successfully formed, perfused, and retrieved uniform, size-controllable, well-conditioned spheroids of human embryonic kidney 293 cells (HEK 293) in the gravity-oriented microfluidic device. We expect the proposed method will be a useful tool to study in-vitro 3-D cell models for the proliferation, differentiation, and metabolism of embryoid bodies or tumours.  相似文献   
206.
207.
This paper presents an integrated distributed cooperative guidance and control scheme for multiple missiles to attack a single target simultaneously at desired impact angles. The scheme is divided into two parts: individual part and cooperative part. For the individual part, partial integrated guidance and control method is adopted to generate the elevator deflection (which is a realistic control input) to ensure that the missiles fly along their respective desired line of sight and hit the target; this is in contrast to previous works which analyze only the engagement dynamics and use missile accelerations as the control input, however, the proposed controller also considers the missile dynamics, thus enabling the implementation of an autopilot. For the cooperative part, using only information from adjacent missiles, the proposed distributed cooperative controller can make all missiles hit the target simultaneously. Hence in this scheme, each missile can hit the target at desired angles and at the same time, thus achieving salvo attack. Simulations are performed to verify the effectiveness of the scheme.  相似文献   
208.
国内外政务社交媒体研究评述及展望   总被引:1,自引:0,他引:1  
[目的/意义] 本研究对国内外政务社交媒体相关研究进行梳理,分析现有研究的特点及不足,以期为政务社交媒体研究提供参考和借鉴。[方法/过程] 通过文献调研,对2014-2019年的国内外政务社交媒体研究进行系统归纳,梳理现有研究的特点及不足,以期为政务社交媒体研究提供参考和借鉴。[结果/总结] 分析发现近年的政务社交媒体研究多为量化研究,分析方法包括内容分析法、统计分析法、社会网络分析法、机器学习方法,研究主题集中于政务社交媒体的运营管理、内容挖掘、应急管理、功能与作用。现有研究存在着数据来源较为单一、数据分析方法有待优化、缺乏系统规范的研究范式等方面的不足,并从政府和公众两个视角为政务社交媒体的未来研究提供思路。  相似文献   
209.
构建了基于层次结构的网页自动分类系统;探讨了该系统中涉及的各项关键技术和构建方法;实现了平面分类和层次分类两种分类方法,并对两种分类方法在网络基础教育资源的环境下进行测试,给出了评价与分析.实验表明,层次分类方法有利于提高分类效率和分类效果.  相似文献   
210.
Student socialization in interdisciplinary doctoral education   总被引:2,自引:0,他引:2  
Interdisciplinary approaches are often seen as necessary for attacking the most critical challenges facing the world today, and doctoral students and their training programs are recognized as central to increasing interdisciplinary research capacity. However, the traditional culture and organization of higher education are ill-equipped to facilitate interdisciplinary work. This study employs a lens of socialization to study the process through which students learn the norms, values, and culture of both traditional disciplines and integrated knowledge production. It concludes that many of the processes of socialization are similar, but that special attention should be paid to overcoming organizational barriers to interdisciplinarity related to policies, space, engagement with future employers, and open discussion of the politics of interdisciplinarity.  相似文献   
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