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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.
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   
3.
According to the United Nations Convention on the Rights of the Child, children have a right to have their views listened to, and studies have shown that doing so can improve their motivation and self‐esteem. Accordingly, this systematic literature review sought to investigate how the views of children with an autism spectrum disorder (ASD), who have difficulties with social communication, may be gathered. Searches of electronic databases yielded 20 studies which met the criteria for inclusion. Semi‐structured interviews (SSIs) were popular, but there is tentative evidence that these are better suited to older, or more academically able, participants. Some of the evidence suggests adaptations to make SSIs more accessible to young people with ASD. Initial evidence has also emerged regarding the suitability of focus groups and electronic diaries. More focused evaluation by researchers of the suitability of their chosen data‐gathering methods for participants with ASD would allow broader conclusions to be drawn.  相似文献   
4.
This review presents a conceptual framework and supporting evidence that links impaired motor control after sport-related concussion (SRC) to increased risk for musculoskeletal injury. Multiple studies have found that athletes who are post-SRC have higher risk for musculoskeletal injury compared to their counterparts. A small body of research suggests that impairments in motor control are associated with musculoskeletal injury risk. Motor control involves the perception and processing of sensory information and subsequent coordination of motor output within the central nervous system to perform a motor task. Motor control is inclusive of motor planning and motor learning. If sensory information is not accurately perceived or there is interference with sensory information processing and cognition, motor function will be altered, and an athlete may become vulnerable to injury during sport participation. Athletes with SRC show neuroanatomic and neurophysiological changes relevant to motor control even after meeting return to sport criteria, including a normal neurological examination, resolution of symptoms, and return to baseline function on traditional concussion testing. In conjunction, altered motor function is demonstrated after SRC in muscle activation and force production, movement patterns, balance/postural stability, and motor task performance, especially performance of a motor task paired with a cognitive task (i.e., dual-task condition). The clinical implications of this conceptual framework include a need to intentionally address motor control impairments after SRC to mitigate musculoskeletal injury risk and to monitor motor control as the athlete progresses through the return to sport continuum.  相似文献   
5.
ABSTRACT

To maintain the accuracy of squash shots under varying conditions, such as the oncoming ball’s velocity and trajectory, players must adjust their technique. Although differences in technique between skilled and less-skilled players have been studied, it is not yet understood how players vary their technique in a functional manner to maintain accuracy under varying conditions. This study compared 3-dimensional joint and racket kinematics and their variability between accurate and inaccurate squash forehand drives of 9 highly skilled and 9 less-skilled male athletes. During inaccurate shots, less-skilled players hit the ball with a more open racket, demonstrating a difference in this task-relevant parameter. No joint kinematic differences were found for accuracy for either group. Coordinated joint rotations at the elbow and wrist both displayed a “zeroing-in” effect, whereby movement variability was reduced from the initiation of propulsive joint rotation to a higher consistency at ball-impact; potentially highlighting the “functionality” of the variability prior to the impact that enabled consistent task-relevant parameters (racket orientation and velocity) under varying conditions. Further, highly skilled players demonstrated greater consistency of task-relevant parameters at impact than less-skilled players. These findings highlight the superior ability of highly skilled players to adjust their technique to achieve consistent task-relevant parameters and a successful shot.  相似文献   
6.
[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   
7.
Purpose: Overuse injuries are common in sport, but complete understanding of injury risk factors remains incomplete. Although biomechanical studies frequently examine musculoskeletal injury mechanisms, human movement variability studies aim to better understand neuromotor functioning, with proposed connections between overuse injury mechanisms and changes in motor variability. Method: In a narrative review, we discuss the variability-overuse injury hypothesis, which suggests repeated load application leads to mechanical tissue breakdown and subsequent injury when exceeding the rate of physiological adaptation. Due to the multidisciplinary nature of this hypothesis, we incorporate concepts from motor control, neurophysiology, biomechanics, as well as research design and data analysis. We therefore summarize multiple perspectives while proposing theoretical relationships between movement variability and lower extremity overuse injuries. Results: Experimental data are presented and summarized from published experiments examining interactions between experimental task demands and movement variability in the context of drop landing movements, along with comparisons to previous movement variability studies. Conclusion: We provide a conceptual framework for sports medicine researchers interested in predicting and preventing sports injuries. Under performance conditions with greater task demands, we predict reduced trial-to-trial movement variability that could increase the likelihood of overuse injuries.  相似文献   
8.
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   
9.
苏鹏  苏成  潘云涛 《图书情报工作》2019,63(20):129-138
[目的/意义]颠覆性技术能变革传统生产模式和消费结构,使产业格局巨变。识别潜在颠覆性技术有助于抢占科技制高点,在科技竞争中取得先发优势。[方法/过程]通过主题检索和引文回溯搜集文献,梳理颠覆性技术现阶段的主要识别方法。[结果/结论]发现方法的选择与研究人员学科背景密切相关,根据研究人员的主要研究领域,将其划分为图书情报、工程管理、经济研究和Christansen流派4类识别方法。在此基础上对识别方法进行7个维度的比较,指出现有方法存在3个问题:过度依赖专家评价、识别标准针对性不足和超前识别效果不佳,其中识别标准针对性不足是核心问题。鉴于此,在后续研究中应当从多种角度不断探究和完善技术颠覆潜力的评价方法。  相似文献   
10.
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