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1.
Smart wheelchairs based on brain–computer interface (BCI) have been widely utilized recently to address certain mobility problems for people with disability. In this paper, we present SmartRolling, an intuitive human–machine interaction approach for the direct control of robotic wheelchair that jointly leverages EEG signals and motion sensing techniques. Specifically, SmartRolling offers two wheelchair-actuation modes for users with different physical conditions: (1) head motion only — people who are severely disabled but able to do basic tasks using eyes and head, and (2) head and hands motion — in addition to type 1, people who can use functioning hands/arms for extra tasks. The system issues operation commands by recognizing different EEG patterns elicited by motor execution (ME) tasks including eye blink, jaw clench, and fist open/close, while at the same time estimates users’ steering intentions based on their facing direction by leveraging inertial measurements and computer vision techniques. The experiment results demonstrate that the proposed system is robust and effective to meets the individual’s needs and has great potential to promote better health.  相似文献   
2.
Abstract

The transformation of library metadata encoded in MARC to linked data will enable libraries to participate in the Semantic Web. This transformation, however, will be an iterative development dependent upon community-based decisions. The PCC, as a community-based organization, is ideally positioned to lead this transformation. As PCC guides this transition, three broad areas must be resolved: the conversion of legacy data to linked data, the use of identifiers to support controlled headings, and the transformation of current workflows to linked-data counterparts. By embracing the Web as a community, PCC can confirm its relevance in a complex web of global data.  相似文献   
3.
[目的/意义]随着知识服务平台的发展,如何通过评估改善知识服务平台的功能和设计以更好地服务于用户成为重要的问题。本文旨在探讨知识服务平台的评估要素和评估标准,为知识服务平台的评估实践提供理论指导。[方法/过程]从信息检索系统评估出发,回顾和梳理信息检索系统评估、数字图书馆评估的相关研究和理论模型、数字图书馆的评估要素和标准。[结果/结论]基于总结和归纳以往信息服务类系统的评估要素,结合知识服务平台的特征,阐述知识服务平台评估的要素和评估标准。  相似文献   
4.
采用文献法、测试法、数理统计等方法,以武汉市十三个行政区内528名以太极拳为主要体育健身方式的老年人为样本,以马步蹲起、弓箭步蹲起、肘撑侧桥、肘撑侧桥举腿等与日常生活活动相关联的四个基础动作为测试内容。研究表明,受试人群普遍存在下肢与躯干的功能性力量不足、左右侧肌肉链力量不均衡的问题。虽然样本人群经常进行以太极拳为主要形式的体育锻炼,但在锻炼过程中侧重于套路技能的演练,对功能性力量训练的认识不足及缺乏相应的训练方法,存在科学性盲区,需要引起重视。  相似文献   
5.
Although Affirmative Action policies have been enforced in many countries, their consequences are highly understudied, especially in the context of developing economies. Section 12(1)(c) of the Right to Education (RTE) Act enforced in 2009 is the first attempt to introduce affirmative action in primary schools in India. The act requires all private schools to reserve at least twenty five percent seats for children from economically weaker sections. To understand the effect of the act on i) social integration and ii) academic outcomes, we asked 1500 children (grades one to three) from four schools to answer friendship surveys and short tests in Mathematics and English. The schools in our sample vary considerably in constitution and were intentionally chosen to understand the impact of the act in different school settings. The friendship surveys show strong homophily i.e. non-RTE students cite other non-RTE students as friends, while RTE students chose to be friends primarily with other RTE students. Trends in test scores reveal that students admitted under the RTE quota score significantly lower than non-RTE students. However, RTE students who have a higher share of non-RTE friends have better test scores, suggesting that affirmative action may have a positive influence on learning outcomes for RTE children. Further we note that commitment from the school authorities and systematic monitoring and evaluation of the implementation of the act will go a long way in bringing out some of the benefits that this act was designed to achieve. Our findings have important policy implications with respect to ensuring proper implementation of the Section12(1)(c) of the RTE act in schools across the country.  相似文献   
6.
首先对中国知网数据库中收录的以警察体育为主题的文献时序分布进行梳理,通过论文发表时间与数量的变量关系对比,分析揭示该研究领域的历史脉络、发展速度以及演变规律。随后利用信息可视化软件Bibexcel绘制出警察体育研究领域的核心作者、研究机构、高被引文献的知识图谱,阐释该领域的研究结构、力量分布以及合作平台建设等情况。最后运用词频分析、共词聚类和可视化法生成关键词共现网络图谱,挖掘、提炼文献数据背后的规律与逻辑,捕捉警察体育研究领域中的研究热点和前沿动态,并在此基础上深入探讨警察体育未来研究的基本趋势和发展方向。  相似文献   
7.
8.
《Sport Management Review》2020,23(2):330-347
Akin to other sports, professional tennis is urged to adopt a consumer-centred strategy and understand the influence of the star status of elite players on demand for its core product. Measuring the impact that tennis players have on demand for match attendance remains a key element towards achieving that goal. Using data from the Australian Open ticket sales, the authors demonstrate how individual players have influenced stadium attendance at the Grand Slam. Findings indicate that some players are associated with a strong positive impact on demand for tickets, above and beyond their performance ratings, reflecting their value to the Australian Open. The authors discuss how this star status can be used to inform business decisions related to tournament management, match scheduling, and determining player appearance fees, to ultimately drive better commercial outcomes and deliver a world-class sporting event. The findings have implications for tournament organisers, player managers and those that market player activities.  相似文献   
9.
This study investigates the extent to which university teachers’ beliefs about classroom writing assessment are congruent with their self-perceived practices in English-as-a-foreign-language (EFL) contexts, and what factors contribute to belief-practice inconsistencies. Drawing on data from a survey of 136 Chinese university EFL writing teachers and ten teacher interviews, results showed a degree of belief-practice alignment regarding assessment for learning (AfL) practices that make learning explicit, but belief-practice discrepancies were more salient. AfL practices that empower students to take responsibility in writing assessment were perceived to be more important than assessment of learning practices; however, the reverse was found in teachers’ practice. Impacts of micro-level factors including assessment training, teaching experience, student attributes, meso-level school factors, and macro-level assessment culture are discussed, and implications are drawn.  相似文献   
10.
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