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排序方式: 共有4035条查询结果,搜索用时 15 毫秒
31.
32.
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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Stewart M Brower 《Journal of the Medical Library Association》2004,92(4):412-420
BACKGROUND: The analysis included forty-one academic health sciences library (HSL) Websites as captured in the first two weeks of January 2001. Home pages and persistent navigational tools (PNTs) were analyzed for layout, technology, and links, and other general site metrics were taken. METHODS: Websites were selected based on rank in the National Network of Libraries of Medicine, with regional and resource libraries given preference on the basis that these libraries are recognized as leaders in their regions and would be the most reasonable source of standards for best practice. A three-page evaluation tool was developed based on previous similar studies. All forty-one sites were evaluated in four specific areas: library general information, Website aids and tools, library services, and electronic resources. Metrics taken for electronic resources included orientation of bibliographic databases alphabetically by title or by subject area and with links to specifically named databases. RESULTS: Based on the results, a formula for determining obligatory links was developed, listing items that should appear on all academic HSL Web home pages and PNTs. CONCLUSIONS: These obligatory links demonstrate a series of best practices that may be followed in the design and construction of academic HSL Websites. 相似文献
35.
This study is a social media analysis on the use of Twitter at Historically Black Colleges and University (HBCU) libraries. While information science researchers have begun examining how libraries use social media, the vast majority of these studies are situated at large flagship research-intensive universities. Additionally, there currently exist deficiencies in research on social media deployment at HBCU libraries. We leverage, the IBM Watson's analytic engine, to systemically examine over 23,000, tweets over an eighteen-month period, around a set of objective measures including propagation of retweets and sentiment to assess follower engagement. The analysis found little evidence of follower engagement with library generated content. However, we observed a substantial volume of library tweets coalesced around institutional boosterism, rather than library related phenomena. This non-library related content represented the vast majority of retweets, but paradoxically was propagated by non-followers. Additionally, tweets relating to institutional boosterism produced the most positive sentiment within the data. 相似文献
36.
I. V. Zibareva L. Yu. Ilina B. L. Alperin 《Scientific and Technical Information Processing》2018,45(2):106-109
The current state of the Russian Science Citation Index is analyzed. Several areas for its further development identified by long-standing active users, such as data searching, refinement, and storage; current user alerts; data input with the Science Index license; patent information; and the application programming interface (API) are investigated. 相似文献
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V. V. Arutyunov 《Scientific and Technical Information Processing》2017,44(1):64-68
This article considers the dynamics and specifics of training highly qualified scientific staff (philosophy doctors and doctors of sciences) in the field of information security and data protection in a 10-year period of 2004–2013 in basic research specialties as classified by the Higher Attestation Commission (VAC) of the Ministry of Education and Science of the Russian Federation. 相似文献
40.
This paper demonstrates the application of module arithmetic for controlling the level of information security by a new technique referred as integer splitting. The basic definitions and concepts of the method are provided. The mathematical function of arising transformation is described in detail; its properties were studied and the basic theorems were proven that justify the use of splitting in practical applications. An active system was designed and characteristic cases of its operation are considered. 相似文献