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21.
领域知识的生长演化问题一直是图书情报学界重点关注的主题。以网络科学思维探索知识生长过程中的关联关系涌现问题,能够对知识关联的生长模式与机制进行揭示。本研究提取知识关联关系累计44万余对,关联频度87万余次,共划分为11个时间窗口。在对时间序列领域知识网络结构属性初步判识的基础上,对关联频度分布进行时间序列分析。并从领域知识生长过程中的关联频度数量、关联频度占比、邻近窗口状态等方面,对知识关联关系及其频度进行跟踪与分析。研究结果表明,知识关联关系生长过程中,关联关系频度的分布符合幂律分布,且在领域知识发展的成熟期表现得更好。知识关联关系的生长过程具有频度层面的“富者更富”的属性,且主要遵循“择优强化”机制。尽管研究所使用的基于社会化标注系统的知识网络尚不足以囊括所有类型的知识网络,但是基于频度演化的知识关联关系涌现模式与机制,有助于促进知识网络、知识生长等领域的研究工作,对于社交网络、传播网络、交通网络等研究不无裨益。图5。表4。参考文献30。 相似文献
22.
Growing numbers of pupils with autistic spectrum disorders (ASD) are attending mainstream schools, and increasing numbers of additional staff are being deployed to support them. Recent research has cast doubt on the effectiveness of this support, by highlighting issues relating to deployment and training, and to relationships with class teachers. This study, conducted by Wendy Symes, who is a Research Associate at the University of Manchester, and Neil Humphrey, who is Professor of Education in the same university, interviewed 15 teaching assistants supporting pupils with ASD in four mainstream secondary schools in the north‐west of England to explore these issues. Analysis yielded several key findings. The majority of teaching assistants worked with just one pupil at a time and worked in a variety of lessons. Their role primarily involved helping pupils to stay focused and follow instructions. Many teaching assistants had no experience of ASD prior to starting their job. The amount of training received varied, but all felt that generic training about ASD was not helpful. A lack of time for joint planning with teachers was raised as a key concern. These findings are discussed in relation to the growing literature on inclusive education for pupils with ASD. 相似文献
23.
Emma Gore Langton Norah Frederickson 《Journal of Research in Special Educational Needs》2016,16(4):254-263
‘Pathological demand avoidance’ (PDA) describes a pattern of difficulties increasingly recognised as forming part of the autistic spectrum. Although clinical reports suggest that children with PDA are likely to experience considerable difficulties in education, their educational experiences have not yet been explored in any systematic way. In the current study, 42 parents of children with PDA completed a questionnaire about their child's educational experiences. Parents' responses indicated that this group of children displays high levels of problem behaviours in school, and receives corresponding high levels of special educational need support and professional involvement. Despite this support, the group had experienced high rates of exclusion and placement breakdown, with only 48% now in mainstream education. Parents reported relatively high satisfaction in their children's educational placements, with success defined by parents in terms of child outcomes, school characteristics and PDA‐specific factors. Findings are discussed with reference to what is known about the educational experiences of children with more typical autism spectrum conditions and in terms of the implications for the inclusion of this group of children with complex needs. 相似文献
24.
Barry Carpenter 《British Journal of Special Education》2011,38(1):37-43
Foetal alcohol spectrum disorder (FASD) is the most common non‐genetic cause of learning disability, affecting around 1% of live births in Europe, and costing an estimated $2.9 million per individual across their lifespan. In adulthood, non‐reversible brain damage is often compounded by secondary disabilities in adulthood, such as mental health problems and drug addiction. The challenge for today's educators is: ‘How do we teach children with FASD?’ Their unusual style of learning and their extreme challenging behaviour is out of the experience of many teachers. This article, written by Professor Barry Carpenter, OBE, National Director of the Specialist Schools & Academies Trust Complex Learning Difficulties and Disabilities Research Project, considers the status of FASD in the UK, and provides an overview of the author's recent research into effective educational strategies within the framework of Every Child Matters. Only government‐led approaches can lead to improvements in the quality of teaching and learning for children with FASD and their future life chances. 相似文献
25.
26.
孙天川 《湖州师范学院学报》2006,28(1):50-53
利用定向图的邻接矩阵的特性,得到了定向图的邻接谱的谱半径的一个可达上界.设D为n阶的定向图,则其邻接谱的谱半径ρ(D)≤n2-1.当n为奇数时,上式取得等号当且仅当D为n2-1出度正则(入度正则);当n为偶数时,不等式严格成立. 相似文献
27.
实轴增量式光电编码器测量电路的设计 总被引:1,自引:0,他引:1
李劲松 《实验室研究与探索》2007,26(2):12-15
介绍了如何设计增量式光电编码器的输出信号处理电路,并从该电路设计的四个方面着手,较为详细地阐述了电路组成的构思、设计及实现过程。 相似文献
28.
控制系统中相关性能指标之间关系分析 总被引:1,自引:0,他引:1
陆锦军 《南通职业大学学报》2004,18(4):26-28
本文比较详尽地推导和分析了二阶控制系统频域指标谐振频率及频宽与时域指标之间的关系,即ωr与ξ的关系、ωr与Mr的关系、ωb与ξ的关系、ωb与Mr的关系,并编写了MATLAB程序,画出了关系曲线;从而对分析和设计控制系统带来了极大的方便。 相似文献
29.
本文研究了一种硅高频高跨导JFET的设计和制造技术,测量结果表明,所研制的器件性能基本达。到了国际上先进公司同类产品的指标参数。 相似文献
30.
一位院士的情怀对科技期刊编辑的启示——阅读《大家博友》《大师小文》的感悟 总被引:1,自引:0,他引:1
针对学术期刊数字化程度与影响力提升的效应问题,重点对江苏省17种中文地学类期刊的网络化建设及应用程度做了调研和量化分析,并将其数据与统计期刊近5年的影响因子和被引频次做了分析比较.结果显示,被统计期刊学术影响力指标的上升趋势,与评价期刊数字化应用程度高低的得分值有很好的对应关系.进一步分析结果表明,代表期刊数字化程度较高的微信运用,有可能对提升科技期刊学术影响力起到意想不到的推动作用. 相似文献