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71.
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Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome. 相似文献
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Kristine M Alpi 《Journal of the Medical Library Association》2005,93(1):97-103
OBJECTIVE: The article explores the characteristics of public health information needs and the resources available to address those needs that distinguish it as an area of searching requiring particular expertise. METHODS: Public health searching activities from reference questions and literature search requests at a large, urban health department library were reviewed to identify the challenges in finding relevant public health information. RESULTS: The terminology of the information request frequently differed from the vocabularies available in the databases. Searches required the use of multiple databases and/or Web resources with diverse interfaces. Issues of the scope and features of the databases relevant to the search questions were considered. CONCLUSION: Expert searching in public health differs from other types of expert searching in the subject breadth and technical demands of the databases to be searched, the fluidity and lack of standardization of the vocabulary, and the relative scarcity of high-quality investigations at the appropriate level of geographic specificity. Health sciences librarians require a broad exposure to databases, gray literature, and public health terminology to perform as expert searchers in public health. 相似文献
74.
Linda M Hartman Rebecca A Abromitis Alice B Kuller Barbara A Epstein 《Journal of the Medical Library Association》2005,93(2):271-277
OBJECTIVE: A staff development committee (SDC) was convened to implement staff development opportunities for an academic health sciences library system comprised of three separate facilities. The charge for the SDC was to: (1) develop programs to enhance workplace skills and personal growth, (2) communicate the availability of existing programs at the university and medical center, and (3) encourage the staff to participate in these opportunities. PROGRAM: The committee created goals and objectives and developed a survey designed to give staff the opportunity to provide input for this initiative. With an 80% response rate, the survey results were used to plan 15 events based on staff needs and preferences. First-year attendance for SDC-sponsored events was 459. Committee members served as liaisons for each event. Two forms were developed to facilitate event planning. A monthly announcement sheet, email reminders, and the library's local area network are used to communicate upcoming SDC events and encourage attendance. CONCLUSION: This approach can serve as a useful model for similar program planning in any organization. 相似文献
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ABSTRACTLighting a cultural heritage artifact requires balancing visual perception with preventive conservation, by providing the best lighting (in terms of spectral distribution and quantity) to enable the viewer to appreciate details and color, while limiting photo-induced degradation. The paper outlines the methodology applied by a multi-disciplinary team while lighting the Shroud of Turin at its last public exhibition in 2015. The methodology considered the special requirements of the Shroud, including exposure to ultraviolet light, while providing appropriate display conditions that would meet audience expectations. The desired appearance (readability of the body image and color) was defined with the help of Shroud researchers and confirmed by subjective tests, while appropriate light levels for preservation were set in agreement with standard requirements and using knowledge of the degradation of linen in visible and UV light. The installation provided a controlled environment and a managed visitor route to the Shroud, assuring excellent perception of both details and color, with the lowest illuminance level about 15?lx. 相似文献
77.
This research analyzed a dataset of academic libraries' posts on Facebook. It applied a text and data analytics approach to a dataset collected from the Facebook posts of academic libraries at the top 100 English-speaking universities, as listed by the 2014 Shanghai World University Rankings. The dataset is from a two-year posting history of 18,333 unique posts, 113,621 likes, and 3401 comments. Less than a quarter of the libraries had more than 2000 post-related likes, and only seven received more than 100 comments on their postings. Content analysis identified the most prevalent single word (unigrams), bigrams (two-word sequences), and trigrams (three-word sequences) in high and low engagement content. Semantic analysis identified the semantic categories for posts with high and low engagement. The findings can assist academic libraries in their social media strategies for engagement, marketing, and visibility. 相似文献
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Yu. N. Schuko 《Scientific and Technical Information Processing》2018,45(3):163-167
Although the USSR and the United States had a comparable number of employees in the field of scientific information, there was a substantial difference in funding, which resulted in a lack of information support for Soviet scientists. While 90% of the publications in the United States were available almost immediately after their release, in the USSR they were delayed by 1.5 to 2 years. Since the publication of the Abstracts Journal by VINITI (AJ), its content was consistently expanding and reached its peak in 1990 (1.5 million documents per year). The next quarter of a century was characterized by a decline in both the composition of the AJ and the time required for its document coverage. The steps for restructuring VINITI activities are discussed. The focus is made on improving the limited coverage of the Russian-language part of the global flow of scientific information by Western information systems. 相似文献