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排序方式： 共有7469条查询结果，搜索用时 15 毫秒
31.
Lingle VA 《Medical reference services quarterly》1996,15(1):41-55
Benchmarking is a quality improvement tool that is increasingly being applied to the health care field and to the libraries within that field. Using mostly resources assessible at no charge through the Internet, a collection of information was compiled on benchmarking and its applications. Sources could be identified in several formats including books, journals and articles, multi-media materials, and organizations. 相似文献
32.
Journal searching in non-MEDLINE resources on Internet Web sites 总被引：1，自引：0，他引：1
Lingle VA 《Medical reference services quarterly》1997,16(3):27-43
Internet access to the medical journal literature is absorbing the attention of all relevant parties, i.e., publishers, journal vendors, librarians, commercial providers, government agencies, and end users. Journal content on the Web sites spans the range from advertising and ordering information for the print version, to table of contents and abstracts, to downloadable full text and graphics of articles. The searching parameters for systems other than MEDLINE also differ extensively with a wide variety of features and resulting retrieval. This discussion reviews a selection of providers of medical information (particularly the journal literature) on the Internet, making a comparison of what is available on Web sites and how it can be searched. 相似文献
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Ward RV 《Osler Library newsletter》1977,(24):1-3
A paper read at the first regular meeting of the Osler Society of McGill University, October 19, 1921. 相似文献
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In Information Retrieval, since it is hard to identify users’ information needs, many approaches have been tried to solve
this problem by expanding initial queries and reweighting the terms in the expanded queries using users’ relevance judgments.
Although relevance feedback is most effective when relevance information about retrieved documents is provided by users, it
is not always available. Another solution is to use correlated terms for query expansion. The main problem with this approach
is how to construct the term-term correlations that can be used effectively to improve retrieval performance. In this study,
we try to construct query concepts that denote users’ information needs from a document space, rather than to reformulate initial queries using the term correlations
and/or users’ relevance feedback. To form query concepts, we extract features from each document, and then cluster the features into primitive concepts that are then used to form
query concepts. Experiments are performed on the Associated Press (AP) dataset taken from the TREC collection. The experimental evaluation
shows that our proposed framework called QCM (Query Concept Method) outperforms baseline probabilistic retrieval model on
TREC retrieval. 相似文献
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