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31.
This study investigated whether anticipation and search strategies of goalkeepers are influenced by temporally and spatially manipulated video of a penalty. Participants were clustered into three groups depending on skill: goalkeepers (n = 17), field players (n = 20) and control group (n = 20). An eye tracker was worn whilst watching 40 videos of a striker kicking to four corners of a goal in random order. All 40 videos were temporally occluded at foot-to-ball contact, and the non-kicking leg of 20 videos was spatially manipulated. Results showed that goalkeepers had significantly better predictions than the two groups with no differences between the two testing conditions. According to effect size, the percentage of fixation location and viewing time of the kicking leg and ball were greater for the goalkeepers and field players group than the control group irrespective of testing conditions. The fixations on the kicking leg and ball in conjunction with comparable predictions between spatially manipulated and control conditions suggest that goalkeepers may not rely on the non-kicking leg. Furthermore, goalkeepers appear to use a global perceptual approach by anchoring on a distal fixation point/s of the penalty taker whilst using peripheral vision to obtain additional information.  相似文献   
32.
In soccer, home teams win about 67% of decided games. The causes for this home advantage are still unresolved. There is a shortage of research on the psychological states of actors involved. In this study, we examined soccer coaches’ expectations, goal setting and tactical decisions in relation to game location. Soccer coaches (N = 297) with different expertise levels participated in an experimental, online management game and were randomly assigned to one of two groups, “home game (HG)” or “away game.” Participants received information on the game for which they were asked to make decisions in multiple points. The only differing information between groups was game location. Regardless of expertise, HG coaches had higher expectations to win, set more challenging goals and decided for more offensive and courageous playing tactics. Possible consequences of these findings concerning home advantage in soccer are discussed.  相似文献   
33.
介绍了一种以 STC89C52单片机为控制核心的智能小车的设计。设计由电机驱动模块、超声波测距模块、循迹模块、红外和语音模块组成,拟实现一个无人驾驶公交车系统。通过 C 语言编程实现小车的前进倒退、转向行驶、自动循迹导航、超声波测距,并根据检测障碍物距离调整速度、红外遥控定点播报功能,实现智能控制,达到设计目标。该系统电路结构简单、功耗低、稳定性高,具有一定实际应用价值。  相似文献   
34.
为了对遮挡情况下的运动车辆进行跟踪,提出一种基于分块的车辆跟踪算法。该算法将目标车辆以可重叠的方式划分为若干大小一致的子块。在分块的基础上估计所有子块的运动矢量,检测噪声运动矢量并进行调整,以减少运动矢量估计的误差,然后对子块进行移位以实现车辆跟踪。为了处理车辆间的遮挡现象建立了马尔可夫随机场描述子块之间的关系,利用欧氏距离定义块的邻域,并基于块的直方图构建能量函数,最后利用模拟退火法对能量函数进行优化,以对遮挡区域进行分割。实验结果表明,该算法能够对遮挡车辆进行准确跟踪。  相似文献   
35.
Peer-teaching is widely established in anatomy teaching and offers well-described advantages. Nevertheless, at Ulm University, Germany, a reduction in the number of peer teacher applicants for the dissection course was observed. This study examined factors related to the attractiveness of a position as a peer teacher for Generation Z students. Participants of the gross anatomy course were asked to evaluate factors influencing the attractiveness of a peer teacher position using a six-point Likert scale. Additionally, open-ended questions were analyzed qualitatively. Sex-specific subgroup analysis was performed comparing students of low and high motivation to apply for a tutorship. Of the 374 students who participated in this study (response rate 53%), 38% stated that they were intending to apply as peer teachers. Data indicated that students displayed intrinsic motivation to apply for a tutorship because of the opportunity to improve their anatomy knowledge and/or their pleasure in teaching. In contrast, extrinsic factors like remuneration of the tutorship and its relevance for their curriculum vitae were least important. Anatomy educators underestimated the demotivating factor of the workload associated with the tutorship and encouraged students less frequently to apply than peer teachers. Only minor sex-specific differences could be identified. Nevertheless, female students were encouraged less frequently to apply than their male peers. In summary, Generation Z students apply as peer teachers because they are enthusiastic about the task. To motivate students to commit to extracurricular activities like a tutorship, anatomy educators should actively encourage students—particularly females—more frequently to apply.  相似文献   
36.
This research aims to promote our understanding of feedback engagement processes in writing tasks using a combination of online and offline measures, including eye-tracking, thinking-aloud, and text-analyses. Study 1 explored how sixteen students read, evaluate, and use feedback for revision. Results revealed three feedback processing strategies: (1) superficial processing (n = 6), which is characterized by reading feedback in a linear way, without critically rereading or revising the text, (2) local processing (n = 6) in which students switched between reading the comments and the commented text, and (3) deep processing (n = 4) in which students integrated the feedback with both commented and uncommented parts of the text and made more substantial revisions. In Study 2, we investigated the local and deep feedback reading strategy in more detail with 41 students using a within-subject design with different types of feedback. Results demonstrated the same strategies among students, but also that the focus of feedback affected students' revision behavior, above and beyond an individual feedback processing strategy. This finding is in line with previous research that emphasized the effects of feedback characteristics on students’ use of feedback. By triangulating various process measures, this research is one of the first that provides empirical evidence for different feedback processing strategies among students. These novel insights in individual feedback engagement processing can be used to extend and refine current theories on how, when, and why feedback works and for whom.  相似文献   
37.
目的:研究渐进运动对恶化性肺部真菌感染的感染过程,分析斑点追踪指导治疗方法对肺部真菌感染恶化过程的临床指导。方法:以某运动疾病康复治疗医院从2014年1月到2014年3月收治的85例肺部真菌感染患者为分析对象,对患者的肺部真菌感染过程进行全程监控,对恶化过程每天进行观察记录,综合提取肺部真菌感染的斑点分布特性与斑点运动特性,比较伊曲康唑、霉素B脂质体、氟康唑三种药物代谢过程的斑点特性,给出真菌感染度及恶化趋势,最后采用相应药物进行治疗。结果:不同感染和恶化程度的肺部真菌感染斑点分布复杂,运动特性各异,随着真菌感染恶化加剧,斑点分布更加随机化,且运动特性明显加剧。结论:渐进运动对渐进恶化性的肺部真菌感染的斑点追踪具有很好的临床参考价值,可以依据斑点特性对肺部真菌感染恶化特性做出准确预测。  相似文献   
38.
在人体运动跟踪建模中,需要对样本集的多样性特征进行贫化处理,以提高全关节驱动模式运动状态跟踪的准确性。传统方法采用量子进化和粒子滤波算法进行人体运动跟踪贫化算法实现,算法在全关节多样化样本特征运动模式下,跟踪效果不好。提出一种采用动态分层二值进化处理的改进的量子进化粒子滤波全关节驱动模式跟踪方法,解决多样本特征的贫化问题。进行人体全关节驱动模式动力学分析及人体运动跟踪模型构建,通过动态分层处理技术,获得二值前景图像,求得人体关节的全方位信息特征,通过动态分层二值进化方法,准确地找到各关节位置,构建亮度模型函数,实现贫化处理。实验表明,改进算法能实现对体操运动员运动幅度大的肘、腕、踝部位均得到了准确的跟踪结果,贫化效果较好,运动状态估计精度较高。  相似文献   
39.
无线传感器网络WSN发射功率的优化调度是决定WSN使用寿命和提高WSN性能的关键,WSN路由节点的在进行数据转发时会导致热点随机扩散,发射功率无法难以实现最大化。提出一种基于路由热点循迹修正的WSN发射功率调度算法。设计了WSN节点路由热点循迹数据传输模型,对发射功率消耗能量模型采用一个高斯衰减信道建模,采用直线反馈线性化补偿方式对路由热点的偏移轨迹进行超负荷状态评估,采用贪婪算法生成一条多分簇路由链,对路由循迹轨迹进行修正,得到WSN优化发射功率的调度递推公式,实现能耗最佳的功率优化调度。实验结果表明,采用该优化调度方法,在准确实现热点循迹修正,传输功率较传统方法稳定,波动较小,WSN可靠性和生存性增强。  相似文献   
40.
Employers’ recruitment behaviour in entry labour markets is central for young people’s transitions from school to work. Whereas previous research has focused on the effects of specific applicant characteristics, I concentrate on how organisational characteristics, namely organisation size and private or public sector affiliation, relate to selection decisions in the dual apprenticeship system in Germany which is a major entry labour market. Following organisational and institutional theory, I expect early selection stages to be more open at larger and public organisations in contrast to smaller private organisations. I also investigate how different organisations respond to school grades as applicants’ signals of skills. I use field experiment data combining organisational-level and applicant-level data to analyse how actual employer responses to written applications by fictitious young people vary with organisation type. The results indicate that, net of applicant characteristics and occupation-specific practices, applications are more likely to receive an invitation to a follow-up selection stage if submitted to larger organisations, and especially larger public organisations, rather than to smaller private organisations. This finding extends to applicants with poorer school grades. Public sector affiliation, however, did not seem to matter much within the group of smaller organisations.  相似文献   
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