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61.
针对集装箱龙门起重机的具体工况需求和特点,构建一种适用于集装箱龙门起重机的增程式混合动力系统,提出并分析该动力系统的能量智能控制策略,设计相应的智能控制模型.通过以动力电池组的荷电状态(State Of Charge, SOC)和集装箱龙门起重机运行能量需求为模糊输入,以动力电池组的充电功率为模糊输出,实现了对增程式混合动力系统的智能控制.仿真结果验证了该控制策略和控制模型的可行性和有效性.  相似文献   
62.
Abstract

Quiet eye training (QET) may be a more effective method for teaching children to catch than traditional training (TT) methods, but it is unclear if the benefits accrued persist in the long term. Thirty children were randomly allocated into a QET or TT group and, while wearing a mobile eye tracker, underwent baseline testing, training and two retention tests over a period of eight weeks, using a validated throw and catch task. During training, movement-related information was provided to both groups, while the QET group received additional instruction to increase the duration of their targeting fixation (QE1) on the wall prior to the throw, and pursuit tracking (QE2) period on the ball prior to catching. In both immediate (R1) and delayed (R2, six weeks later) retention tests, the QET group had a significantly longer QE1 duration and an earlier and longer QE2 duration, compared to the TT group, who revealed no improvements. A performance advantage was also found for the QET compared to the TT group at both R1 and R2, revealing the relatively robust nature of the visuomotor alterations. Regression analyses suggested that only the duration of QE1 predicted variance in catch success post-training, pointing to the importance of a pre-programming visuomotor strategy for successful throw and catch performance.  相似文献   
63.
Clutch performance is improved performance under pressure. However, little research has examined the psychological state experienced by athletes in these situations. Therefore, this study qualitatively examined the subjective experience underlying clutch performance across a range of sports (e.g., team, individual) and standards (Olympic to recreational athletes). Sixteen athletes (Mage = 27.08 years; SD = 6.48) took part in in-depth, semi-structured interviews primarily after an exceptional performance (M = 4.38 days later; SD = 3.14). Data were analysed inductively and thematically. Clutch states involved 12 characteristics, including heightened and deliberate concentration, intense effort, and heightened awareness, which distinguished the experience of clutch from other optimal psychological states such as flow. Other characteristics, such as perceptions of control, were also reported and supported previous experimental research on clutch. These findings present in-depth qualitative insights into the psychological state underlying clutch performance, and are discussed in relation to the existing literature on optimal psychological states in sport.  相似文献   
64.
为提高自主式水下机器人(Autonomous Underwater Vehicle,AUV)控制系统的鲁棒性,将分层递阶结构与包容式结构相结合,提出了一种混合式控制体系结构,开发了基于VxWorks的微小型AUV控制系统.该系统以“海事金枪鱼”号AUV为载体,以嵌入式PC104计算机为系统核心,通过传感器的信息融合、算法实现和多任务运行,控制系统驱动推进器、舵、翼等执行单元实现AUV的姿态调整、导航和路径规划,最终达到自主作业的目的.“海事金枪鱼”号AUV的开发应用,验证了方案的可行性以及控制系统的可靠性和稳定性.  相似文献   
65.
[目的/意义]针对当前知识发现服务中存在的个性化程度不高和推荐效果不佳等问题,提出一种基于用户兴趣度量和内容分析的推荐算法。[方法/过程]文章通过特征词分布、LDA主题分布、引文结构网络三个维度构建学术资源模型,并通过对用户行为的度量,计算用户对其浏览学术资源的兴趣度,结合学术资源模型构建用户兴趣模型。将用户兴趣模型与学术资源模型匹配,计算其相似度,得到用户对每条学术资源的兴趣值,最后将兴趣值最高的TOP-N学术资源推荐给用户。[结果/结论]通过实验检验算法的有效性和推荐准确率,结果显示,本文从实时动态度量兴趣的角度,提出的推荐算法能较好地预测用户兴趣,推荐效果显著,为实现发现服务精准推荐提供思路。  相似文献   
66.
体育精准扶贫:逻辑起点、实践探析与推进策略   总被引:1,自引:0,他引:1  
体育精准扶贫是一种重要但受到忽视的精准扶贫模式。将体育纳入精准扶贫中,采用"体育+健康"、"体育+文化"、"体育+旅游"、"体育+产业"等多种组合扶贫模式,能推动贫困地区在健康、文化脱贫的同时,在经济上也同步脱贫,从而构成体育精准扶贫的逻辑起点。从实践探索来看,体育精准扶贫存在精准识别方法不成熟、精准识别对象不均衡、精准帮扶主体比较单一、精准帮扶措施比较简单、精准帮扶脱离靶向、精准脱贫成效的保障机制不健全等困境。最后,结合以上问题,从加强顶层设计等方面提出了有针对性的政策建议。  相似文献   
67.
The current study compared changes in neuromuscular control between slackline training and the stabilization training elements of the FIFA 11+ programme. Twenty-five students in 2 groups performed a 12-unit training programme. The slackline training group (n?=?13) exclusively trained with a slackline. The stabilization training group (n?=?12) practised exercises as described in the second part of the FIFA 11+ programme. Improvements in balance were assessed using three tests for dynamic, quasi-static, and perturbed postural control: the star excursion balance test (SEBT), the closed-eye single-leg stance, and the MFT S3-Check. Both groups significantly improved the stability and sensorimotor index of the MFT S3-Check (p?<?.001), their range on the SEBT (p?<?.001), and the duration of closed-eye single-leg stance (p?<?.001). The group?×?training interaction was significant for the MFT S3-Check (stability index: p?=?.042; sensorimotor index: p?=?.004) and the SEBT (dominant leg: p?=?.003; averaged both legs: p?=?.016), with the slackline training group showing a larger training effect than the stabilization training group. The results of the present study suggest that slackline training offers similar – or better – improvements in neuromuscular control as the FIFA 11+ warm-up programme. If compliance with the FIFA 11+ programme is declining, then slacklining might offer an alternative approach to reach the training goals of improved sensorimotor control.  相似文献   
68.
This study aims to assess fundamental movement skill (FMS) proficiency, physical self-confidence levels, and the relationship between these variables and gender differences among adolescents. Three hundred and ninety five adolescents aged 13.78 years (SD = ±1.2) from 20 schools were involved in this study. The Test of Gross Motor Development-2nd Edition (TGMD), TGMD-2 and Victorian Skills Manual were used to assess 15 FMS. Participants’ physical self-confidence was also assessed using a valid skill-specific scale. A significant correlation was observed between FMS proficiency and physical self-confidence for females only (r = 0.305, P < 0.001). Males rated themselves as having significantly higher physical self-confidence levels than females (P = 0.001). Males scored significantly higher than females in FMS proficiency (P < 0.05), and the lowest physical self-confidence group were significantly less proficient at FMS than the medium (P < 0.001) and high physical self-confidence groups (P < 0.05). This information not only highlights those in need of assistance to develop their FMS but will also facilitate in the development of an intervention which aims to improve physical self-confidence and FMS proficiency.  相似文献   
69.
以工作过程为导向进行高职课程改革,关键在于根据工作实境创设学习情境,并依据学习情境整合课程内容,改善教学方法,实现理实一体化.在高职环境类专业《水污染控制技术》课程改革中,针对特定的学习目标,在对工作岗位和行动能力分析的基础上形成课程体系,并按照岗位工作过程合理设置和序化教学内容,同时综合运用多种教学手段和方法,有效提升学生的专业技能和综合素质.  相似文献   
70.
城市土地资源的稀缺性使得成熟地段的新房交易数量急剧减少,二手房的交易量稳步攀升,二手房贷款逐渐升温。但我国二手房贷款市场存在的问题还很多,深入地分析和探索这些问题,寻找解决的办法和对策,对于稳定二手房交易有着十分重要的意义。  相似文献   
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