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排序方式: 共有820条查询结果,搜索用时 15 毫秒
1.
Chaos theory, informational needs, and natural disasters 总被引:2,自引:0,他引:2
Timothy L. Sellnow Matthew W. Seeger Robert R. Ulmer 《Journal of Applied Communication Research》2002,30(4):269-292
This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning. 相似文献
2.
论网络环境下情报检索语言的发展趋势 总被引:2,自引:0,他引:2
本文论述了网络环境下采用自然语言是必然趋势,然而自然语言并不会成为网络环境下的唯一检索语言,自然语言和人工语言相结合才是发展的方向.参考文献8. 相似文献
3.
本文论述什么是中文自然语言理解技术,详细说明如何理解,智能搜索引擎如何应用中文自然语言理解技术进行检索。 相似文献
4.
Antonio G. Valdecasas Virginia Correia Ana M. Correas 《Museum Management and Curatorship》2006,21(1):32-43
The first natural history collections opened to the public were inspired by a sense of curiosity and wonder about the products of nature. They were ‘cabinets of curiosities’ that offered a first-hand interaction between owner and visitors. Nowadays, these two facets of the museum experience—dialogue and wonder—have been lost, in part, due to the information overload coming via the media and the impersonal nature of the museum visit. This paper offers some reflections on the evolution of the museum visit, suggests some ways to rediscover this ‘sense of wonder’ and provides ideas on how to promote two-way communication with museum visitors. Two examples of exhibitions are offered as illustrations of the points discussed. 相似文献
5.
为考察共词分析在研究领域聚合中的有效性,本研究以1988年~2017年三十年间发表且收录于WoS(Web of Science)数据库的计算机科学、地理学、数学、应用化学和应用物理学等五个学科的标题、摘要和关键词为分析对象,对不同分析单元下所聚合的研究领域的表面效度进行了检验。研究发现,关键词在研究领域聚合中具有相对最高的表面效度,摘要和题名的效度则相对较低。然而,本研究也发现,科学计量领域现有聚类指标和工具所聚合的研究领域缺乏区分能力且各种指标均存在着一定的效度风险。本研究的发现对于丰富科学计量领域关于研究领域聚合有效性的认识具有重要理论意义。 相似文献
6.
伽伯·西萨巴 《自然科学博物馆研究》2018,(1):40-43
匈牙利自然历史博物馆是世界上最早的自然历史博物馆之一,具有独特的传统并在社会中发挥着决定性的文化作用。馆内收藏有丰富的植物学、动物学、人类学、古生物学和地质学的藏品、原生型标本以及藏书,为世界各地研究人员的研究活动提供收藏品和设施。该馆每年举办的展览吸引观众约30万人次,组织近500场教育活动,受众达到了44000人。该馆意识到博物馆当前所面临的挑战与机遇,积极应对诸如气候变化、生物多样性危机、新发传染病、生物入侵等全球性问题,在探索与相关政府部门以及其他科学组织和机构合作方式过程中发挥主导作用。 相似文献
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8.
The objective of the present study was to determine whether it is possible to design a video game that could help students improve their executive function skill of shifting between competing tasks and the conditions under which playing the game would lead to improvements on cognitive tests of shifting. College students played a custom video game, Alien Game, which required the executive function skill of shifting between competing tasks. When students played for 2 h over 4 sessions they developed significantly better performance on cognitive shifting tests compared to a control group that played a different game (d = 0.62), but not when they played for 1 h over 2 sessions. Students who played Alien Game at a high level of challenge (i.e., reaching a high level in the game) developed significantly better performance on cognitive shifting tests compared to controls when they played for 2 h (Experiment 1, d = 1.44), but not when they played for 1 h (Experiment 2). Experiment 3 replicated the results of Experiment 1 using an inactive control group, showing that playing Alien Game for 2 h resulted in significant improvements in shifting skills (d = 0.78). Results show the effectiveness of playing a custom-made game that focuses on a specific executive function skill for sufficient time at an appropriate level of challenge. Results support the specific transfer of general skills theory, in which practice of a cognitive skill in a game context transferred to performance on the same skill in a non-game context. 相似文献
9.
白洋淀是华北平原最大的淡水湖泊湿地,被誉为华北平原生态环境的寒暑表,然而由于人为不合理的开发利用导致湿地生态环境退化.从湿地生境安全保护的角度提出了白洋淀湿地生物多样性及其安全栖息生境的保护对策, 相似文献
10.