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101.
ABSTRACT

Current awareness is something that librarians do, at least informally, passing on relevant current information to their patrons on a regular basis. The type of current awareness service considered here entails running preselected searches against electronic databases. The availability of these electronic bibliographic databases allows automating much of the current awareness process. Any successful current awareness service will have three key attributes: speed, ease of use, and relevance. The flexibility and accessibility of the National Library of Medicine's PubMed make it ideal as the basis for a current awareness service. Six freely available services are evaluated according to uniform criteria with notes made of special features. Four services use PubMed as the source for data, and the other two use MEDLINE. Recommendations are made for modifying one of the services to embody the key attributes of a successful service. Particular attention is given to local needs. Such a service can be run from a single desktop machine with a dial-up connection to the Internet.  相似文献   
102.
One of the challenges of intelligent systems for education is to use low-level data collected in computer environments in the form of events or interactions to infer information with high-level significance using artificial intelligence techniques, and present it through visualizations in a meaningful and effective way. Among this information, emotional data is gaining track in by instructors in their educational activities. Many benefits can be obtained if an intelligent systems can bring teachers with knowledge about their learner’s emotions, learning causes, and learning relationships with emotions. In this paper, we propose and justify a set of visualizations for an intelligent system to provide awareness about the emotions of the learners to the instructor based on the learners’ interactions in their computers. We apply these learner’s affective visualizations in a programming course at University level with more than 300 students, and analyze and interpret the student’s emotional results in connection with the learning process.  相似文献   
103.
Enhanced battlefield visualization for situation awareness   总被引:1,自引:0,他引:1  
We present tools to visualize density, clustering, and lethality assessment that help a military commander achieve situation awareness on the battlefield. For the density computation, we provide a geometry-based, image-based, and hybrid approach to tackle the problem. We choose proximity-based clustering as a suitable definition for our application. Based on this clustering definition, we show an efficient computational method based on the Delaunay triangulation. Finally, we present a probabilistic model for the lethality assessment and an efficient way to compute it using hardware support where available. We also explain how to deliver visual information to the human visual system effectively. The principles of human visual perception, such as preattentive and Gestalt perceptual processing, play an important role in this work.  相似文献   
104.
如何利用多源异构时空数据进行准确的轨迹预测并且反映移动对象的移动特性是轨迹预测领域的核心问题.现有的大多数轨迹预测方法是长序列轨迹模式预测模型,根据历史轨迹的特点进行预测,或将当前移动对象的轨迹位置放入时空语义场景根据历史移动对象轨迹预测位置.综述当前常用的轨迹预测模型和算法,涉及不同的研究领域.首先,阐述了多模式轨迹预测的主流工作,轨迹预测的基本模型类;其次,对不同类的预测模型进行总结,包括数学统计类、机器学习类、滤波算法,以及上述领域具有代表性的算法;再次,对情景感知技术进行了介绍,描述了不同领域的学者对情景感知的定义,阐述了情景感知技术所包含的关键技术点,诸如情景感知计算、情景获取和情景推理的不同类模型,分析了情景感知的不同分类、过滤、存储和融合以及它们的实现方法等.详细介绍了情景感知驱动的轨迹预测模型技术路线及各阶段任务的工作原理.给出了情景感知技术在真实场景中的应用,包括位置推荐,兴趣点推荐等,通过与传统算法对比,分析情景感知技术在此类应用中的优劣.详细介绍了情景感知结合LSTM (long short-term memory)技术应用于行人轨迹预测领域的新方法.最后,总结了...  相似文献   
105.
经过多年的JSP技术课程的实践教学,总结出了一套行之有效的教学思路,把JSP技术课堂设计成为5个教学环节:励志教育、温故引新、情境教学、推行问题、教学检测这5部分能够兴趣化地向学生传授知识,教会学生结合实际勇于创新、勤于思考、积极实践。  相似文献   
106.
在社会的飞速发展中,科学技术也在与时俱进,信息传播的渠道有传统的模式发展到了网络模式,随着计算机网络时代的到来,人们的生存方式也发生了翻天覆地的改变,平面设计也引入了新的观念和新的元素,充分利用网络资源带来的便利,以思想和情感的表达为基础,设计出符合时代要求的作品。本文将对网络时代平面广告的文化意识进行探究,简单了解其中的变化。  相似文献   
107.
We describe how interactive paper can be used together with a multi-channel web information system to build a platform for experimenting with multi-modal context-aware mobile information services. As an application, we present a tourist guide for visitors to an international festival that was developed to investigate alternative modes of information delivery and interaction in mobile environments. The guide is based around a set of interactive paper documents—an event brochure, map and bookmark. The brochure and map are augmented with digital services by using a digital pen to activate links and a text-to-speech engine for information delivery. The digital pen is also used for data capture of event ratings and reviews. The bookmark provides access to advanced searches and ticket reservations. We describe the architecture and operation of the system, highlighting the challenges of extending a web information system to support both the generation of the paper documents and the interaction from these documents, alongside more traditional access channels. Finally, we discuss the range of context-aware interactions that is supported by our platform.  相似文献   
108.
文章结合目前各种网络业务系统对安全管理的迫切需求,设计了面向业务的安全管理模型,分析了模型中涉及的安全事件关联分析技术和安全态势感知技术等关键技术,并就安全管理的发展趋势进行了探讨.  相似文献   
109.
Research on collaborative learning traditionally assumes a certain degree of symmetry between the learning partners in terms of both their learning-relevant traits and their individual learning outcomes. However, if one collaborative partner is clearly more able, skilled, or knowledgeable than the other partner, then it remains unclear who profits more from the collaboration. The present study aimed to explore this issue by manipulating symmetry in prior knowledge within small groups of online learners (dyads) and measuring their problem-solving efficiency and incidental learning gain on an individual and dyad level. Awareness of this symmetry/asymmetry was manipulated, too, to discern it as a potential moderator. Dyads with symmetrical and asymmetrical prior knowledge performed equally well on most measures. Moreover, on average, the more and the less knowledgeable partners in the asymmetrical conditions had equal learning gains. However, while in dyads with symmetrical knowledge learning gains were correlated between the partners, in the asymmetrical dyads they were not. Awareness of symmetry/asymmetry did not act as a moderator, but, overall, dyads with awareness of each other's knowledge learned more from each other than dyads without such awareness. The benefit of awareness was, however, specific to the learning content exposed via awareness. We conclude that researchers and practitioners should be careful when choosing or assigning collaborative partners to each other, as only for partners with symmetrical prior knowledge can a symmetrical increase in knowledge be expected. We further discuss the implications of these findings for research on knowledge awareness and collaboration.  相似文献   
110.
Ambient awareness refers to the awareness social media users develop of their online network in result of being constantly exposed to social information, such as microblogging updates. Although each individual bit of information can seem like random noise, their incessant reception can amass to a coherent representation of social others. Despite its growing popularity and important implications for social media research, ambient awareness on public social media has not been studied empirically. We provide evidence for the occurrence of ambient awareness and examine key questions related to its content and functions. A diverse sample of participants reported experiencing awareness, both as a general feeling towards their network as a whole, and as knowledge of individual members of the network, whom they had not met in real life. Our results indicate that ambient awareness can develop peripherally, from fragmented information and in the relative absence of extensive one-to-one communication. We report the effects of demographics, media use, and network variables and discuss the implications of ambient awareness for relational and informational processes online.  相似文献   
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