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991.
Do young children appreciate the importance of access to premises when judging what another person knows? In Experiment 1, 5-year-olds (N=31) were sensitive to another person's access to premises when predicting that person's ability to point to a target after eliminating alternatives in a set of 3 cartoon characters. Experiment 2 replicated the finding when 5- to 6-year-olds (N=102) judged who the other person thought the target was, and whether the other person knew who the target was. Experiment 3 demonstrated that children aged 5-7 years (N=107) more successfully imputed inference by elimination than syllogistical inferential knowledge. Findings suggest that an early understanding of inference by elimination offers a route into understanding that people can sometimes gain knowledge without direct perceptual access. 相似文献
992.
Research suggests that undergraduate students learn more from lab experiences that involve longer-term projects. We have developed a one-semester laboratory sequence aimed at sophomore-level undergraduates. In designing this curriculum, we focused on several educational objectives: 1) giving students a feel for the scientific research process, 2) introducing them to commonly used lab techniques, and 3) building skills in both data analysis and scientific writing. Over the course of the semester, students carry out two project-based lab experiences and write two substantial lab reports modeled on primary literature. Student assessment data indicate that this lab curriculum achieved these objectives. This article describes the first of these projects, which uses the biflagellate alga Chlamydomonas reinhardtii to introduce students to the study of flagellar motility, protein synthesis, microtubule polymerization, organelle assembly, and protein isolation and characterization. 相似文献
993.
Bill Kennedy 《Publishing Research Quarterly》2010,26(3):187-192
A concise review is presented of the essential elements of the book publishing and bookselling business in a complex and diverse
market. Demographics create the diversity while Arabic is the one language spoken across a multitude of different countries.
Three features are common to all of these countries and they are: the dominance of English as the second language, education
has and will remain to be a priority, and economic pressures cause price sensitivity to be a major challenge especially in
the educational market segments. It is the price sensitivity as a key factor for the lack of respect for intellectual property
and copyright regulations. A review of distribution and retail stores is a very important topic in relation to this complex
collection of countries. The emergence of e-books is discussed especially in the educational, professional and reference market
segments. Finally, there is a review of the Arabic language publishers and local book fairs to bring this article to closure. 相似文献
994.
995.
We explore the feasibility of automatically identifying sentences in different MEDLINE abstracts that are related in meaning.
We compared traditional vector space models with machine learning methods for detecting relatedness, and found that machine
learning was superior. The Huber method, a variant of Support Vector Machines which minimizes the modified Huber loss function,
achieves 73% precision when the score cutoff is set high enough to identify about one related sentence per abstract on average.
We illustrate how an abstract viewed in PubMed might be modified to present the related sentences found in other abstracts
by this automatic procedure. 相似文献
996.
David E. Losada 《Information Retrieval》2010,13(5):485-506
The retrieval of sentences that are relevant to a given information need is a challenging passage retrieval task. In this
context, the well-known vocabulary mismatch problem arises severely because of the fine granularity of the task. Short queries,
which are usually the rule rather than the exception, aggravate the problem. Consequently, effective sentence retrieval methods
tend to apply some form of query expansion, usually based on pseudo-relevance feedback. Nevertheless, there are no extensive
studies comparing different statistical expansion strategies for sentence retrieval. In this work we study thoroughly the
effect of distinct statistical expansion methods on sentence retrieval. We start from a set of retrieved documents in which
relevant sentences have to be found. In our experiments different term selection strategies are evaluated and we provide empirical
evidence to show that expansion before sentence retrieval yields competitive performance. This is particularly novel because expansion for sentence retrieval is often done after sentence retrieval (i.e. expansion terms are mined from a ranked set of sentences) and there are no comparative results available between both
types of expansion. Furthermore, this comparison is particularly valuable because there are important implications in time
efficiency. We also carefully analyze expansion on weak and strong queries and demonstrate clearly that expanding queries
before sentence retrieval is not only more convenient for efficiency purposes, but also more effective when handling poor
queries. 相似文献
997.
998.
999.
Business opportunities in international markets are largely determined by accessibility, transparency, and legal frameworks
fair to all parties concerned. Arab book markets in principle offer a tremendous potential with more than 300 million readers
sharing one common language. Besides unsolved censorship issues, problems with money collection, and differing regulations,
however, the lack of a uniform book distribution system is the most critical hurdle for the development of a common Arabic
book market. Most importantly, there is no comprehensive database containing accurate content briefs, background information
on authors, ISBN numbers, and publisher company information as well as all relevant commercial data such as book prices, weight,
logistics terms, and availability. Authors and publishers are hard hit as they often need to organize book transportation,
delivery, and invoice collection on their own. At present, “selling book fairs” in the Arab world—with the exception of Abu
Dhabi International Book Fair—present themselves as crowded book bazaars rather than executive meeting points. The authors
of the article, however, are anticipating change: New distribution initiatives will soon interlink regional Arabic markets
and create unique growth and profit opportunities. 相似文献
1000.
Donghee Sinn 《Archival Science》2010,10(2):117-140
Archivists have long tried to understand users from the viewpoint of their archival collections. Such an approach misses important
perspectives about use in, and users of, archives; how they perform research and develop knowledge while using archives. This
study aims to comprehend the use of archival materials in research from the users’ perspective. It attempts to understand
users’ perceptions of the impact of archival collections on their research, how and when archival materials are involved in
the research process and how much weight they grant those materials in support of their thesis, from an actual research topic,
the No Gun Ri massacre. The case of the No Gun Ri incident provides a good example of how archival materials play a role in historical discussions and an opportunity to look
at archival contributions. No Gun Ri researchers acknowledged that archival documents were essential source materials for details about the incident and a major
player in stimulating controversies and, consequently, provided the impetus for further publications. General recordkeeping
situations also provided a circumstantial context of the incident. However, No Gun Ri researchers agreed that oral history was the most valuable and influential evidence for their major ideas and used archival
documents to provide hard facts about the details of oral history. There are some unique research patterns of No Gun Ri researchers identified in this study which are different from the typical assumptions of archivists. 相似文献