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941.
The effects of query structures and query expansion (QE) on retrieval performance were tested with a best match retrieval system (InQuery1). Query structure means the use of operators to express the relations between search keys. Six different structures were tested, representing strong structures (e.g., queries with facets or concepts identified) and weak structures (no concepts identified, a query is a bag of search keys). QE was based on concepts, which were first selected from a searching thesaurus, and then expanded by semantic relationships given in the thesaurus. The expansion levels were (a) no expansion, (b) a synonym expansion, (c) a narrower concept expansion, (d) an associative concept expansion, and (e) a cumulative expansion of all other expansions. With weak structures and Boolean structured queries, QE was not very effective. The best performance was achieved with a combination of a facet structure, where search keys within a facet were treated as instances of one search key (the SYN operator), and the largest expansion. 相似文献
942.
Twyla J. Hill 《Publishing Research Quarterly》1998,14(1):36-45
Most analyses of multicultural children's books concentrate on published works by white authors and the implications of their
depictions of non-white characters. This article explores the production process of multicultural children's literature. The
differences between multicultural and culturally conscious literature are discussed. The production and distribution processes
of children's books are described. Interview data is used to highlight areas of these systems which constrain the production
of books by non-white authors. 相似文献
943.
944.
J. Mark Schuster 《Journal of Cultural Economics》1998,22(2-3):127-150
This paper takes a preliminary look at the hybridization of museums – the creation of a variety of mixed forms of governance incorporating both public and private governing authorities. Using data from three national surveys of American museums, the analysis documents the mix of types of governing authority and demonstrates how this mix varies across location, over time, and by museum type. The paper then estimates the extent of hybridization using several different indicators and speculates about its implications. The United States offers a particularly informative case because the general view is that American museums are (1) either public or private and (2) predominately private. While the second part of this view may still be a useful characterization of American museums, the first is no longer a particularly helpful way of understanding American museums, or, by extension, other cultural institutions, American or not. It is increasingly necessary to view cultural institutions through the lens of hybridization rather than privatization in order to improve our ability to document and predict their institutional behavior. 相似文献
945.
J. Avenhaus R. Gotzhein T. H?rder L. Litz K. Madlener J. Nehmer M. Richter N. Ritter D. Rombach B. Schürmann und G. Zimmermann 《Informatik - Forschung und Entwicklung》1998,13(4):227-234
Ohne Zusammenfassung 相似文献
946.
947.
Bracewell PJ 《Journal of sports sciences》2003,21(8):611-620
The performance of individual rugby players can be quantified using multivariate analysis and modified control chart methodology. Using factor analysis, multivariate data are reduced to five orthogonal factors (key performance indicators). These factors are reduced to a single measure of performance by modifying control chart ideology. By comparing the observed peformances with 'unattainable perfection' rather than the average, a statistic that is suitable for monitoring the performance of individual rugby players with control charts is obtained for use by coaches and selectors. 相似文献
948.
Margaret H. Collins David J. Pearsall Gerald S. Zavorsky Hamid Bateni Rene A. Turcotte David L. Montgomery 《Journal of sports sciences》2013,31(2):83-90
The aims of this study were to determine if there are significant kinematic changes in running pattern after intense interval workouts, whether duration of recovery affects running kinematics, and whether changes in running economy are related to changes in running kinematics. Seven highly trained male endurance runners (VO 2max = 72.3 +/- 3.3 ml kg -1 min -1 ; mean +/- s) performed three interval running workouts of 10 X 400 m at a speed of 5.94 +/- 0.19 m s -1 (356 +/- 11.2 m min -1 ) with a minimum of 4 days recovery between runs. Recovery of 60, 120 or 180 s between each 400 m repetition was assigned at random. Before and after each workout, running economy and several kinematic variables were measured at speeds of 3.33 and 4.47 m s -1 (200 and 268 m min -1 ). Speed was found to have a significant effect on shank angle, knee velocity and stride length (P ? 0.05). Correlations between changes pre- and post-test for VO 2 (ml kg -1 min -1 ) and several kinematic variables were not significant (P > 0.05) at both speeds. In general, duration of recovery was not found to adversely affect running economy or the kinematic variables assessed, possibly because of intra-individual adaptations to fatigue. 相似文献
949.
950.
Mary Grace Antony Ryan J. Thomas 《Journal of International and Intercultural Communication》2017,10(1):4-24
The recent migration of 65,000 children across the southwestern border, coupled with allegations of abuse by the U.S. Border Patrol, enables the investigation of an overlooked immigrant category: the unaccompanied youth migrant. Analyzing audience responses to news reports of the abuse, we find that established disparaging immigrant tropes apply, describing the children as an economic burden, disease carriers, and offspring of irresponsible families. We uncover two new themes: Youth migrants are channels whereby criminals may infiltrate the U.S., and manipulate legal authorities to remain in the U.S. Finally, we demonstrate how global compassion is strategically deployed to qualify harsh retaliatory measures. 相似文献