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41.
针对ZigBee技术在无线温度测量系统中的应用,提出了系统的总体构架方案,对系统的硬件和软件进行了详细的分析和设计,并给出该系统的硬件和软件的实现方案.  相似文献   
42.
数据汇聚是降低传感器网络传输能耗的重要手段.分簇传感网数据汇聚通常包括簇内汇聚及传递汇聚结果到基站两个阶段,现有方案大多关注第二阶段数据汇聚结果传递到基站的效率.现提出一种基于位置信息的分簇传感网数据汇聚方案,通过利用位置信息选择代理点,仅与代理点有不同测量值的节点进行数据发送,有效减少了第一阶段中的数据传输.理论分析与模拟试验表明,方案簇内消息发送数优于相关方案,减少了通信开销,延长了网络生命期.  相似文献   
43.
基于物联网技术的校园安防系统设计   总被引:2,自引:1,他引:2  
针对校园安全突发事件增多的现象,提出了将RFID技术、无线传感器网络、ZigBee技术等物联网技术应用于校园安防管理之中,设计了包含RFID校园门禁系统、网络视频监控系统和防火报警系统等多个子系统的整体化校园安防系统,有助于各类学校进行“平安校园”、“智能校园”的建设.  相似文献   
44.
The present study aimed to extend research that has focused on the identification of stressors associated with coaching practice by systematically evaluating how such stressors effect athletes, and more broadly, the coach–athlete relationship. A total of 13 professional- and national-level athletes were interviewed to address the three study aims: how they detect when a coach is encountering stressors, how coach experiences of stress effects them as an athlete, and how effective the coach is when experiencing stress. Following content analysis, the data suggested athletes were able to detect when a coach was experiencing stress and this was typically via a variety of verbal and behavioural cues. Despite some positive effects of the coach experiencing stress, the majority were negative and varied across a range of personal influences on the athlete, and effects on the general coaching environment. It was also the broad view of the athletes that coaches were less effective when stressed, and this was reflected in performance expectations, perceptions of competence, and lack of awareness. The findings are discussed in relation to the existing theory and with reference to their implications for applied practice, future research, and development of the coach–athlete relationship.  相似文献   
45.
It is widely assumed that there is an eccentric hamstring muscle fibre action during the swing phase of high-speed running. However, animal and modelling studies in humans show that the increasing distance between musculotendinous attachment points during forward swing is primarily due to passive lengthening associated with the take-up of muscle slack. Later in the swing phase, the contractile element (CE) maintains a near isometric action while the series elastic (tendinous) element first stretches as the knee extends, and then recoils causing the swing leg to forcefully retract prior to ground contact. Although modelling studies showed some active lengthening of the contractile (muscular) element during the mid-swing phase of high-speed running, we argue that the increasing distance between the attachment points should not be interpreted as an eccentric action of the CE due to the effects of muscle slack. Therefore, there may actually be no significant eccentric, but rather predominantly an isometric action of the hamstrings CE during the swing phase of high-speed running when the attachment points of the hamstrings are moving apart. Based on this, we propose that isometric rather than eccentric exercises are a more specific way of conditioning the hamstrings for high-speed running.  相似文献   
46.
This study extends recent coach stress research by evaluating how coaches perceive their stress experiences to affect athletes, and the broader coach–athlete relationship. A total of 12 coaches working across a range of team sports at the elite level took part in semi-structured interviews to investigate the 3 study aims: how they perceive athletes to detect signals of coach stress; how they perceive their stress experiences to affect athletes; and, how effective they perceive themselves to be when experiencing stress. Following content analysis, data suggested that coaches perceived athletes able to detect when they were experiencing stress typically via communication, behavioural, and stylistic cues. Although coaches perceived their stress to have some positive effects on athletes, the overwhelming effects were negative and affected “performance and development”, “psychological and emotional”, and “behavioural and interaction” factors. Coaches also perceived themselves to be less effective when stressed, and this was reflected in their perceptions of competence, self-awareness, and coaching quality. An impactful finding is that coaches are aware of how a range of stress responses are expressed by themselves, and to how they affect athletes, and their coaching quality. Altogether, findings support the emerging view that coach stress affects their own, and athlete performance.  相似文献   
47.
基于加权DV-Hop算法的无线传感器网络定位技术   总被引:1,自引:0,他引:1  
节点自身定位技术是无线传感器网络的关键技术之一,由于传感器网络资源受限,定位算法需要综合考虑定位精度、通信、计算开销等方面因素.主要通过对DV-Hop算法的分析,提出了加权定位算法,采用信标节点对未知节点的不同影响力来确定加权因子,以提高定位精度.实验结果表明,该算法计算简单,无额外通信开销,定位精度较极大似然估计算法高,具有普遍应用意义.  相似文献   
48.
腰部扭伤为体育运动及生活中的多发病。临床证明,针刺精灵威灵穴为主,配合体针,对多种急慢性腰部扭伤疗效显著。针刺28例,治愈23例,显效4例,好转1例,总有效率100%。  相似文献   
49.
目的:探讨机械拉伸刺激对骨骼肌卫星细胞增殖能力的影响。方法:通过Flexercell细胞拉伸力学装置对骨骼肌卫星细胞施加5%、15%和25%拉伸应变加载实验,用CCK-8法检测细胞受机械刺激后的增殖变化,采用BCA蛋白测定试剂盒测定细胞总蛋白含量。结果:骨骼肌卫星细胞受机械张力刺激后,发现卫星细胞增殖能力增强,蛋白含量增加,其中,15%拉伸应变率的促增殖与对照组有显著性差异(P〈0.01)。结论:机械刺激可以促进体外卫星细胞的增殖能力,细胞增殖能力与细胞所受刺激的负荷大小有关。  相似文献   
50.
采用文献资料法、归纳法以及逻辑分析法,对体育赛事旅游品种及市场前景进行分析,认为这一旅游形式在当前我国旅游业发展中占有重要地位。赛事旅游是国际旅游市场新开发的旅游品种,它将体育赛事与旅游相融合,增加国民体育文化的内涵,并促进比赛举办地的经济、文化发展,国家走体育比赛和旅游产业相结合的道路,大有好处。世界发达国家都十分重视体育赛事旅游,并已形成一定规模,中国的体育赛事旅游尚处于起步阶段,前景广阔,将成为旅游业中的新亮点。  相似文献   
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