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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.
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   
3.
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   
4.
Numerous motor abilities depend on the activity of proprioceptors, which has been suggested to be genetically determined. To test this hypothesis, the control of torque generated by knee extensors and knee position was studied in 30 father–son pairs both before and immediately after running. After stabilisation of the participant in a sitting position, the knee joint of his dominant leg was flexed to 90°, and the maximal voluntary torque (MVT) of the dominant knee extensors under static conditions was measured. The participant then tried five times to produce 50% of the MVT. Next, the participant extended the knee to 45° five times without visual control. Significant correlations between the reproducibility of successive trials for groups of fathers and their sons were found. The correlation coefficients for the repeatability of the knee extension torque were 0.69 (confidence interval [CI] = 0.45–0.84; P < 0.01) and 0.75 (CI = 0.54–0.87; P < 0.01) before and after the fatiguing exercise, respectively, whereas the coefficient for the reproducibility of positioning the knee was 0.49 (CI = 0.16–0.72; P < 0.01) after the fatiguing exercise. Our results indicate a significant influence of hereditary factors on the control of limb torque and position.  相似文献   
5.
针对混合型道路公交车辆信号控制问题,综合采用微波、RFID,ZigBee和北斗卫星导航系统等多种传感技术构建公交沿线无线传感器网络,实现对交通运行参数监测、BRT车辆准确定位和无线通讯功能,通过车辆设备与信号机间的信息交互,实现了信号的优先控制,提高了公交的运行速度。  相似文献   
6.
采用内容分析法,从政策工具和技术创新过程两个维度出发,构建生物质能源产业创新政策分析框架,对过去10年(2006—2016年)中国中央政府出台的37份相关政策进行计量分析与评价。研究发现,政策制定主体较为集中,多部门联合发文数量相对较少;从政策工具维度看,市场维度政策工具使用相对不足;从技术创新过程看,政策对于生物质能源产业的扶持呈现"U"型趋势,对"示范"这个阶段关注较少。在此基础上,提出相关建议,为今后政策调整提供依据。  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.
从知识的角度提出颠覆式创新由创新模糊前端、研究开发阶段、目标市场商业化阶段、进入主流市场、建立行业标准,新一轮的颠覆式创新等6个阶段组成,并对每一阶段进行详细剖析。将SECI知识演化模型的社会化,外显化,组合化,内在化与颠覆式创新过程的创新模糊前端,研究开发阶段和商业化阶段结合对应分析,同时将企业外部知识源这一要素加入SECI模型。  相似文献   
10.
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