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1.
Abstract. A multiple baseline design was employed to test the effect of manipulative instruction on the perimeter and area problem‐solving performance of middle and high school students who had been diagnosed with LD in the area of mathematics. Modeling, prompting/guided practice, and independent practice in conjunction with manipulative training were employed to teach both perimeter and area problem‐solving skills. Analysis of data revealed that the students rapidly acquired the problem‐solving‐skills, maintained these skills over a two‐month period, and transferred these skills to a paper and pencil problem‐solving format. This research extends previous findings by revealing that use of concrete manipulatives promotes the long‐term maintenance of skills.  相似文献   
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A user study of the Index Medicus done at the Walter Reed Army Medical Center included responses from a group of sixty researchers, clinicians, residents, and interns. An analysis of the questionnaire shows that, while all respondents use the Index Medicus, most use it to search for a specific subject or a specific author reference. Comments received were critical of the delay from the time of journal publication until the appearance of its citation in Index Medicus. Suggestions were offered concerning the type of publication most of the respondents would prefer.  相似文献   
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This paper characterizes the methodological foundations of national standardization in the Russian Federation, in particular in the library and information field. The activities of Technical Standardization Committee 191 Scientific and Technical Information, Librarianship, and Publishing are reported.  相似文献   
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The basic properties of the blockchain technology are discussed to allow informed decisions on its selection and use in scientific and information activities. Specific examples are given and the efficiency of this technology is analyzed.  相似文献   
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This paper explores the information nature of culture. It is represented as an extragenetic and nonorganizational information process and system. Information is regarded as a universal property of matter that is essentially associated with development processes and realizes various forms and ways of storage and circulation at various development stages of global evolution. The socio-cultural principle of exogenous accumulation, transmission, and transformation of information is analyzed in the context of the continuing growth of the information content of material systems on the superhighway of global-universal evolution. It is noted that the information concept of culture evolves into a new area of cultural studies, that is information and cultural studies, advancing our understanding of the nature of culture and cultural genesis.  相似文献   
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Academic libraries have to a large extent taken the lead in facilitating new approaches to research data management, but changes to the research data landscape have had an impact on numerous areas of academic work, including ethics review. Using interpretive phenomenological analysis of interviews with chairs of Canadian research ethics boards, this study explores how ethics review boards have experienced changes to data policy and related technologies in order to describe the ethical implications of new approaches to data management and to explore ways in which the library, ethics review boards, and other campus partners might harmonize efforts to support emerging data practices. While ethics review boards in Canada are keenly aware of open data policies, data publishing in practice is still nascent. There is uncertainty about the adoption of changing technologies for research and their impacts on privacy protection. Where responsibility lies for addressing these uncertainties is often unclear. Academic libraries and research ethics boards are well-suited to engage in mutual knowledge transfer and to integrate data management planning and ethics review processes. Institutional-level oversight that includes all campus departments impacted by changes to the research data landscape may facilitate improved communication and reduce role ambiguity.  相似文献   
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Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   
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