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81.
Web searchers commonly have difficulties crafting queries to fulfill their information needs; even after they are able to craft a query, they often find it challenging to evaluate the results of their Web searches. Sources of these problems include the lack of support for constructing and refining queries, and the static nature of the list-based representations of Web search results. WordBars has been developed to assist users in their Web search and exploration tasks. This system provides a visual representation of the frequencies of the terms found in the first 100 document surrogates returned from an initial query, in the form of a histogram. Exploration of the search results is supported through term selection in the histogram, resulting in a re-sorting of the search results based on the use of the selected terms in the document surrogates. Terms from the histogram can be easily added or removed from the query, generating a new set of search results. Examples illustrate how WordBars can provide valuable support for query refinement and search results exploration, both when vague and specific initial queries are provided. User evaluations with both expert and intermediate Web searchers illustrate the benefits of the interactive exploration features of WordBars in terms of effectiveness as well as subjective measures. Although differences were found in the demographics of these two user groups, both were able to benefit from the features of WordBars. 相似文献
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83.
Relatively little is known regarding preschool teachers’ use of specific scaffolds, including those high support scaffolds (e.g., co-participating, eliciting, reducing choices) that may be important for children who are struggling to acquire language and literacy concepts. The goal of this study was to characterize preschool teachers’ use of six types of scaffolds (generalizing, reasoning, predicting, co-participating, reducing choices, eliciting; see O’Connor et al. in Ladders to literacy, Paul H. Brookes Publishing, Baltimore, MD, 2005) within the whole group read aloud session. Two specific questions were addressed: (1) To what extent do preschool teachers use high and low support scaffolds during whole group read aloud sessions? and (2) To what extent does preschool teachers’ perceived frequency of use of specific scaffolds correspond to their actual use of scaffolds? Videotaped classroom observations were carried out for five preschool teachers conducting whole group read alouds in their classrooms; frequency of use for six types of scaffolds was coded using systematic observation procedures. Results indicated that teachers showed a preference for three types of scaffolds, all of which were low support, and that the three types of high support scaffolds occurred at very low rates. Additionally, results showed a substantial discrepancy between teachers’ perceived frequency of use of specific types of scaffolds relative to their actual use. Together, findings suggest that preschool teachers may benefit from professional development focused on using a range of scaffolds, to include high support scaffolds beneficial to children who may need high levels of support to participate in read alouds. 相似文献
84.
足球对抗的实质是相互间知行能力的竞争较量,足球对抗的知行特征为对抗中的知彼知己和避实击虚。 相似文献
85.
运用文献资料法,根据我国国民经济发展规划和世界各国的体育产业发展情况,具体分析了我国体育产业的形成、现状和发展趋势,得出结论:21世纪我国体育产业的开发和发展前景广阔,体育产业市场巨大。 相似文献
86.
87.
试论我国《体育法》的修改、完善 总被引:5,自引:1,他引:5
《中华人民共和国体育法》作为我国体育基本法于1995年8月29日颁布以来,发挥了重大的作用。但随着时代的变迁以及《体育法》受“宜粗不宜细”立法思想的指导,本身存在许多缺陷,以至愈来愈不能满足我国体育事业发展过程中对法的需求。因此,修改、完善《体育法》势在必行。运用立法法、行政法、比较法的基本原理对我国《体育法》存在的问题作逐一分析,并在此基础上提出修改《体育法》的具体意见。 相似文献
88.
There is now widespread recognition that digital technologies, particularly portable hand held devices capable of Internet connection, present opportunities and challenges to the way in which student learning is organized in schools, colleges and institutions of higher education in the 21st Century. Traxler, Journal of the Research Centre for Educational Technology, 6(1), 3–15 (2010) suggests such devices are pervasive and ubiquitous, conspicuous and unobtrusive, noteworthy and taken-for-granted with everyone typically owning one, using one and often having more than one. As a consequence it has been argued that the availability of such devices, controlled mainly by the student and not the teacher, has the potential to change the traditional dynamics and pedagogical patterns of the learning environment (Burden et al. 2012). Education institutions, however, typically remain organized around spatial and temporal considerations such as buildings, timetables, calendars and internal structures which are designed to classify and manage students. In the case study reported here students and faculty teaching staff from the College of Education in the Kuwait University were surveyed in order to assess their access to such technologies, their capability to use them effectively in support of achieving planned learning outcomes and the implications for change that could emanate from such findings. 相似文献
89.
90.
Taper angle is one of the effective methods to reduce the dragload and downdrag of piles under the surcharge load. The model tests on the tapered pile and uniform cross-section pile embedded in sand were carried out under the surcharge load. The values of dragload and downdrag of piles versus the surcharge loads were measured. Based on the concentric cylinder shearing theory, a simplified theoretical model for calculating the dragload and downdrag of tapered piles with small taper angles under the surcharge load was proposed considering the angle effect. The correctness of the developed theoretical model was validated through comparing with the model test results obtained in this study and previous literature. Then the parametric studies of the taper angle, surcharge, strength and modulus of soil were discussed. It is shown that the tapered pile with the taper angle of 3° can reduce approximately 65% of the maximum dragload value and 30% of the downdrag value compared with a uniform cross-section pile. The value of downdrag can be decreased by approximately 50% compared with a uniform crosssection pile in the same average pile diameter. 相似文献