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141.
The development of students as lifelong, self-regulating learners is a valued outcome of higher education. To this end, the current project investigated how students in an undergraduate course experienced and responded to a teaching–learning environment where they were expected to take responsibility for their learning. The pedagogic environment of this course was grounded in strategies and activities associated with assessment for learning (AfL). As such, students were expected to participate in activities that provided them with opportunities to exercise control over their learning. Data gathering comprised individual semi-structured interviews and the collection of artefacts. Findings indicated goals helped students know where they were going; exemplars provided insights into what was expected and what constituted quality work; course activities elicited evidence of learning; dialogic interactions around these generated feedback about understandings and progress; the evaluation of exemplars developed evaluative knowledge, skill and expertise; peer review and feedback provided an authentic context for evaluation and monitoring of works-in-progress. It was concluded that, while each of the AfL strategies contributed to student self-regulation, the full impact of AfL as a catalyst for self-regulated learning was realised in the cumulative and recursive effect these strategies had on students’ thinking, actions and feelings.  相似文献   
142.
143.
This article is about personally driven professional development through the use of reflective self-study. The argument that teachers need to take responsibility for their own learning while also taking decisions on how and in what areas to develop is strongly made throughout the article. Data for this article were gathered over a 10-year period where the author engaged in several studies using self-study as methodology. Between studies, the author kept using reflective self-study as a professional development tool, and it is these data between various studies that were analysed using thematic and reflective analysis. Such analysis resulted in various overarching themes that show how reflective self-study can be of benefit if used by teachers researching their own classrooms. Benefits include teachers taking full ownership of their learning, relevance of learning, learning that is ongoing and not restricted to specific times and places, taking problematic situations as learning opportunities and how other sources take on new relevance through reflective self-study. Some implications for teacher-education programmes and current school structures are also discussed.  相似文献   
144.
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   
145.
陆小辉 《现代情报》2006,26(2):125-127
在传统的信息检索中。我们常用检全率、检准率来评价信息检索系统性能和检索效果。随着信息网络化的迅速发展。信息总量的息剧增加。信息交流速度的日益加快,相关性这一信息检索申的关键性概念日益受到人们的重视。本文分析探讨了信息检索中相关性的概念、构成及评价指标,阐述了提高信息检索相关性的措施。  相似文献   
146.
We present new methods of query expansion using terms that form lexical cohesive links between the contexts of distinct query terms in documents (i.e., words surrounding the query terms in text). The link-forming terms (link-terms) and short snippets of text surrounding them are evaluated in both interactive and automatic query expansion (QE). We explore the effectiveness of snippets in providing context in interactive query expansion, compare query expansion from snippets vs. whole documents, and query expansion following snippet selection vs. full document relevance judgements. The evaluation, conducted on the HARD track data of TREC 2005, suggests that there are considerable advantages in using link-terms and their surrounding short text snippets in QE compared to terms selected from full-texts of documents.  相似文献   
147.
This work is devoted to the study of symmetric control systems. It establishes a relation between internal symmetry and external one for a linear invariant control system having n real simple poles. The symmetric stabilization problem is studied using a symmetric feedback gain such that the output control stabilizes the closed-loop system. A necessary and sufficient condition is given to solve this stabilization problem for a symmetric control system (A,B,C) and a generalized symmetric control system (E,A,B,C).  相似文献   
148.
顾定法 《资源科学》1996,18(4):8-14
针对目前我国城市缺水形势严峻,同时又存在大量浪费水和水污染的现象,再一次敲响了水危机的警钟。本文结合城市用水特点,提出了城市用水、节水的基本原理。城市理想的用水系统应该是一个闭环反馈系统,这一系统应该靠节水和污水回用来实现。文中列举大量数据分析城市节水取0城市水资源系统、闭环反馈系统、工业用水重复利用率  相似文献   
149.
Contextual document clustering is a novel approach which uses information theoretic measures to cluster semantically related documents bound together by an implicit set of concepts or themes of narrow specificity. It facilitates cluster-based retrieval by assessing the similarity between a query and the cluster themes’ probability distribution. In this paper, we assess a relevance feedback mechanism, based on query refinement, that modifies the query’s probability distribution using a small number of documents that have been judged relevant to the query. We demonstrate that by providing only one relevance judgment, a performance improvement of 33% was obtained.  相似文献   
150.
基于检索相关性转移的本体论检索系统   总被引:8,自引:1,他引:8  
韩毅 《情报科学》2003,21(2):194-197
本文在讨论了当前情报检索系统的相关性判断基础上,指出在相关性判断的多维度多层次的复杂概念中用户关心的是语用相关,但多数检索系统仅能提供形式相关,运用本体论的基本原理,建立了本体论的情报检索系统,该系统在一定程度上实现了检索的语言相关判断。  相似文献   
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