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41.
文章从区域空间、受教育主体、价值取向三个角度,对“城乡教育”予以辨析。在此基础上,就城乡教育统筹实现度测评体系构建提出以下建议:应当根据教育的分布特征确定有区别的城乡教育划分标准;应当将城乡统筹过程中的农民工子女、留守儿童作为特殊人群予以关注;应当在测评中突出农村特色学校的价值。  相似文献   
42.
本文通过分析社会力量与高校资源的整合,论证兰州市足球协会与西北师范大学共建室内五人制足球俱乐部可行性措施,探索甘肃省室内五人制足球发展的有效途径。为甘肃足球人才的培养机制及如何良性循环创造实践平台,打造西北地区体教结合、特色办学的新型教育模式提供建设性意见。  相似文献   
43.
人体动作姿态的识别是当前研究的热点,而对于运动员技术姿态的计算是非常困难的但其应用十分广泛。针对竞技体操现场中运动员的技术姿态识别展开研究,通过监控设备对竞技体操现场进行图像采集,对图像进行关节点标定,利用加权量化矩阵表示技术姿态特征用以解决不同关节点的权重区分度问题,经过权重修正后的关节点相对坐标作为技术姿态特征用以解决标定关节点时产生的误差所造成的识别精度下降的问题,基于多种姿态特征建立技术姿态描述算子并构建特征数据库,用于训练基于支持向量机的多类分类器,以实现竞技体操现场中对体操运动员技术姿态特征的识别。实验表明,提出的方法实现了11种体操运动员运动姿态的特征识别,在识别效率和精度上具有令人满意的结果。  相似文献   
44.
合资自主品牌的进入是中国汽车工业发展的必然产物,其发展模式的出现受政治、经济、市场环境、企业内部等因素的影响。首次通过结构方程模型,将中国的GDP、乘用车销量、千人保有量、恩格尔系数等影响因素对中国合资自主品牌导入时机进行实证研究。通过引入合资自主品牌导入因子e建立合资自主品牌发展模式数理模型,并借助AMOS统计软件进行模型实现和评价,根据评价指标及各变量的实际内涵对模型进行修正和完善。构建模型在"金砖四国"的印度、俄罗斯等得到验证,希望为发展中国家或市场潜力大的发达国家促进发展汽车合资自主品牌提供可借鉴的进入模式和进入时机的研究方法和方式。量化后的理论模型证实具有可操作性和可复制性。  相似文献   
45.
We investigated joint coordination differences between Taekwondo back kicks and jumping back kicks, and how jumping (in performing the latter) would alter engaging ground reaction forces (GRF) in executing kicking. Ten skilful athletes volunteered to perform both kinds of kicking within the shortest time for three successful trials. Three high-speed cameras and two force platforms were used for data collection, and the trial with the shortest execution time was selected for analysis. Movements were divided into the rotation and attack phases. With comparable execution time and maximum joint linear/angular speeds, back kicks and jumping back kicks differ mainly in larger GRF in the latter, and in greater target acceleration in the former probably because the support leg prevented athletes’ rebounding after impact. In addition, more prominent antiphase and in-phase coordination between the shoulder segment and knee joint, and elongated rotation phase were found in jumping back kicks. Larger GRF values in jumping back kicks were generated for jump take-off rather than for a more powerful attack. In back kicks although the support leg remained ground contact, greatly decreased GRF in the attack phase suggested that the support leg mainly served as a rotation axis.  相似文献   
46.
The ankle joint’s role in shock absorption during landing has been researched in many studies, which have found that landing with higher amounts of plantarflexion (PF) results in lower peak vertical ground reaction forces and loading rates. However, there has not yet been a study that compares drop landings within participants along a quantitative continuum of PF angles. Using a custom-written real-time feedback program, participants adjusted their ankles to an instructed PF angle and dropped onto two force platforms. For increasing PF, peak ground reaction force and peak loading rate during weight acceptance decreased significantly. The hip’s contribution to peak support moment decreased as PF at initial contact increased up to 30°. The ankle and knee contributions increased over this same continuum of PF angles. There appears to be no optimal PF angle based on peak ground reaction force and loading rate measurements, but there may be an optimum where joint contributions to peak support moment converge and the hip moment’s contribution is minimised.  相似文献   
47.
文章通过太极拳运动对膝关节损伤的相关文献查询,得出常见的太极拳运动膝关节损伤病例,对文献结论分析得出造成损伤的因素有两个方面,一是动作技术不正确不规范造成,二是膝关节受力过重造成。通过对和式太极拳三直五顺拳理要求分析,得出五顺是太极拳动作技术要求,三直是减轻膝关节受力要求,与造成膝关节损伤的两个方面具有对应关系,提出三直五顺拳理对练习者的要求在保护膝关节损伤的重要性。  相似文献   
48.
Joint moments can be used as an indicator of joint loading and have potential application for sports performance and injury prevention. The effects of changing walking and running speeds on joint moments for the different planes of motion still are debatable. Here, we compared knee and ankle moments during walking and running at different speeds. Data were collected from 11 recreational male runners to determine knee and ankle joint moments during different conditions. Conditions include walking at a comfortable speed (self-selected pacing), fast walking (fastest speed possible), slow running (speed corresponding to 30% slower than running) and running (at 4 m · s?1 ± 10%). A different joint moment pattern was observed between walking and running. We observed a general increase in joint load for sagittal and frontal planes as speed increased, while the effects of speed were not clear in the transverse plane moments. Although differences tend to be more pronounced when gait changed from walking to running, the peak moments, in general, increased when speed increased from comfortable walking to fast walking and from slow running to running mainly in the sagittal and frontal planes. Knee flexion moment was higher in walking than in running due to larger knee extension. Results suggest caution when recommending walking over running in an attempt to reduce knee joint loading. The different effects of speed increments during walking and running should be considered with regard to the prevention of injuries and for rehabilitation purposes.  相似文献   
49.
木质工字梁(Wood I-Beam,简称:IB)在使用过程中将不可避免地遇到潮湿环境的影响,研究水分对翼缘/腹板接口性能的影响,对确保IB接口最佳胶合状态以及最终产品尺寸稳定性至关重要.研究结果表明:IB的综合性纤维饱和点只有25%左右;含水率从8.9%提高到25%的接口的承压能力下降了47.2%,含水率从25%提高到53%的接口的承压能力仅下降了0.6%;水分对IB翼缘和腹板尺寸变化的影响是水分影响接口承载能力的间接因素;吸湿后接口的承载能力并不能恢复到吸湿前的初始水平;解吸至8.9%含水率的IB接口的承载能力比吸湿前同等含水率的IB接口低了17.8%.  相似文献   
50.
This paper presents a case study of how the interactive whiteboard (IWB) may facilitate collective meaning-making processes in group work in engineering education. In the case, first-year students attended group-work sessions as an organised part of a basic physics course at a Norwegian university college. Each student group was equipped with an IWB, which the groups used to write down and hand in their solutions to the physics problems. Based on a Vygotskian, dialectical stance, this study investigates how the students used the IWB in the group-work situation. From qualitative analysis of video data, we identified four group-work processes where the IWB played a key role: exploratory, explanatory, clarifying and insertion. The results show that the IWB may facilitate a ‘joint workspace’, a social realm in which the students’ dialogues are situated.  相似文献   
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