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1.
《Information processing & management》2023,60(3):103262
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.
Philip E. Schreur 《Cataloging & classification quarterly》2020,58(3-4):397-402
AbstractThe 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.
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
4.
5.
近年来,脑卒中和交通事故造成上肢损伤的人数逐年上升,医疗领域对康复器械的需求越来越大。为满足实际需求,开发以气动人工肌肉为驱动器的4自由度(肩关节外收/内展(被动)、前驱/后伸、肘关节屈曲、腕关节屈曲)可穿戴上肢康复机器人。首先设计上肢康复机器人的结构,并采用气动人工肌肉作为肘关节与腕关节的驱动器。然后针对该上肢康复机器人,研究主动康复训练控制策略,设计两种控制策略。通过穿戴实验验证控制策略的有效性和实际应用价值。 相似文献
6.
Benjamin K. Williams Ross H. Sanders Joong Hyun Ryu Philip Graham-Smith Peter J. Sinclair 《Journal of sports sciences》2020,38(10):1115-1123
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
7.
社会治安问题的加剧,警察院校学生的实战技能逐渐在加强,大力开展防卫控制技能是很多警察院校重点培养后备人民警察的重要举措,通过课程的开展达到强健体魄,防身自卫,安全执法的目的。本文通过文献资料法、社会调查法,专家访谈法,对几所警察院校《防卫控制技术》课程开设情况以及学生的心理情况进行调查,分析并指出了当前防卫控制技能教学存在的主要问题,为以后更好地开展这门课程,培养更多的优秀学生提供一点参考。 相似文献
8.
Qianqian Zhou Tze Ping Loh Tony Badrick Chun Yee Lim 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2021,31(2)
IntroductionIt is unclear what is the best strategy for applying patient-based real-time quality control (PBRTQC) algorithm in the presence of multiple instruments. This simulation study compared the error detection capability of applying PBRTQC algorithms for instruments individually and in combination using serum sodium as an example.Materials and methodsFour sets of random serum sodium measurements were generated with differing means and standard deviations to represent four simulated instruments. Moving median with winsorization was selected as the PBRTQC algorithm. The PBRTQC parameters (block size and control limits) were optimized and applied to the four simulated laboratory data sets individually and in combination.ResultsWhen the PBRTQC algorithm were individually optimized and applied to the data of the individual simulated instruments, it was able to detect bias several folds faster than when they were combined. Similarly, the individually applied algorithms had perfect error detection rates across different magnitudes of bias, whereas the error detection rates of the algorithm applied on the combined data missed smaller biases. The performance of the individually applied PBRTQC algorithm performed more consistently among the simulated instruments compared to when the data were combined.DiscussionWhile combining data from different instruments can increase the data stream and hence, increase the speed of error detection, it may widen the control limits and compromising the probability of error detection. The presence of multiple instruments in the data stream may dilute the effect of the error when it only affects a selected instrument. 相似文献
9.
Thorben Hülsdünker Heiko K. Strüder Andreas Mierau 《European Journal of Sport Science》2018,18(7):955-964
Many sports require athletes to rapidly transform visual information into a targeted motor response, a process referred to as visuomotor reaction. On the behavioural level, athletes have long been established to achieve faster simple visuomotor reaction times when compared to non-athletes. However, although the superior performance in athletes has been attributed to the central nervous system, the underlying neural mechanisms remained poorly studied. More recently, a growing number of neurophysiological and neuroimaging studies systematically addressed the functional and structural modulations in the athletes’ visual and motor systems as well as their contribution to visuomotor performance. This article reviews current research on structural and functional characteristics of the athletes’ cortical visuomotor system associated with simple visuomotor reactions, sports-specific visuomotor performance and visuomotor training. The primary objective is to shed light on the neural mechanisms potentially contributing to superior visuomotor reaction performance in athletes participating in visuomotor demanding disciplines. A more comprehensive understanding of performance-determining neural functions could provide great potential for diagnostics and training to improve athletic performance. 相似文献
10.
Terese L. Chmielewski Justin Tatman Shuhei Suzuki MaryBeth Horodyski Darcy S. Reisman Russell M. Bauer James R. Clugston Daniel C. Herman 《运动与健康科学(英文)》2021,10(2):154
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