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101.
The purpose of this study was to investigate differences in the support leg joint moment and moment power between side-step (SS) and cross-step (CS) cutting techniques with a prescribed 90° cutting angle. Ground reaction forces (1,000 Hz) and three-dimensional kinematics (250 Hz) of SS and CS cutting techniques were collected from 20 male college athletes. Normalised peak knee extension moment was larger in the SS technique than in the CS technique (0.40 ± 0.10 in SS; 0.26 ± 0.08 in CS). In the SS technique, the knee extensors ( ? 0.10 ± 0.06 in SS; ? 0.02 ± 0.04 in CS) and ankle plantarflexors ( ? 0.12 ± 0.05 in SS; ? 0.07 ± 0.03 in CS) did significantly more negative work (normalised). The direction change angle (40.5 ± 8.7° in SS; 33.0 ± 6.8° in CS) and the decrease in horizontal velocity of the centre of mass ( ? 0.63 ± 0.23 m/s in SS; ? 0.31 ± 0.23 m/s in CS) were significantly larger in the SS technique. These results suggest that the SS technique is an effective means of changing running direction at the expense of velocity of the centre of mass and that the CS technique is better for minimising the reduction in horizontal velocity of the centre of mass.  相似文献   
102.
运动性膝关节损伤的临床康复   总被引:3,自引:0,他引:3  
针对膝关节不稳定性损伤的不同状态,对不同运动强度,不同运动开始时间在损伤康复研究中的价值进行比较研究,为运动性膝关节损伤的临床康复提供参考。  相似文献   
103.
本文对158例胸椎小关节紊乱患者进行了病因诊断及手法机理的临床探讨,提出了胸椎突然旋转外力是导致该症的病因。其临床症状复杂,主要是由于小关节紊乱或滑膜嵌顿引起的局部炎症和刺激植物神经的结果。手法治疗效果显著,简单实用。  相似文献   
104.
提高合并高样图书馆办馆效益的思考   总被引:11,自引:1,他引:10  
高校图书馆合并后已取得了初步效益,但仍存在一些问题,如何解决这些问题以实现合并办馆的最大效益,更好地为高校提供信息服务,以达到高校合并改革之目的,值得深入思考。  相似文献   
105.
This study adopted a longitudinal retrospective case study approach to investigate Chinese business students’ transitional learning experience in a problem-based learning (PBL) course with innovative assessment practices. The study focused on students’ beliefs and strategy use in a constructively aligned PBL course for business communication. Eight students who had made notable progress were chosen for retrospective analysis. The data included 48 journal entries, interviews, and writing samples collected at different stages of the course. This study identified taxonomies of participants’ beliefs about learning and writing, their perceptions of assessment, and their strategy use for learning. It also examined changes in beliefs, perceptions, and strategy use to determine the nature of the students’ learning experience in this PBL course. Findings suggest a recognised need to design PBL courses that align social constructivist learning principles with students’ beliefs and strategies. The results also highlight the importance of developing appropriate assessment rubrics to enhance student engagement with PBL learning for improved outcomes.  相似文献   
106.
赵伟  童根树 《科技通报》2006,22(3):377-384
高频焊接矩形管生产效率高,抗扭性能好,平面外刚度大,根据需要内部可充填混凝土以提高抵抗局部屈曲的能力,比焊接H型钢的轻钢厂房有更好的经济性。为提高梁柱连接节点的承载力、减小节点变形,需在节点区外包槽钢。本文分析了节点区不同厚度、不同形式外包槽钢和不同的柱内加劲肋设置等对节点强度和刚度的影响,得出了满足刚性连接要求的节点区外包槽钢厚度计算公式。研究了柱加劲肋、螺栓排列、螺栓数目、槽钢宽度和槽钢下伸长度等的影响。建议了箱形柱柱顶与梁上翼缘齐平,槽钢与梁端板等厚,槽钢向上伸出长度以满足安装一排高强螺栓的要求,并设置三角形加劲肋与柱顶盖板和槽钢焊接,箱形柱顶和槽钢内面满焊的节点形式。分析表明这种节点有很高的刚度和强度,能满足刚性连接的要求。  相似文献   
107.
This paper examines some of the combinatorial issues associated with the batch data association problem arising in tracking and correlation applications. A procedure is developed that addresses a large class of data association problems involving the calculation of permanents of submatrices of the original association matrix. This procedure yields what is termed the Joint Assignment Matrix (JAM), which can be used to optimally rank associations for hypothesis selection. Because the computational cost of the permanent scales exponentially with the size of the matrix, improved algorithms are developed both for calculating the exact JAM and for generating approximations to it. Empirical results suggest that at least one of the approximations is suitable for real-time hypothesis generation in large scale tracking and correlation applications. Novel theoretical results include an improved upper bound on the calculation of the JAM and new upper bound inequalities for the permanent of general nonnegative matrices. One of these inequalities is an improvement over the best previously known inequality.  相似文献   
108.
In this paper, we propose a new language model, namely, a dependency structure language model, for topic detection and tracking (TDT) to compensate for weakness of unigram and bigram language models. The dependency structure language model is based on the Chow expansion theory and the dependency parse tree generated by a linguistic parser. So, long-distance dependencies can be naturally captured by the dependency structure language model. We carried out extensive experiments to verify the proposed model on topic tracking and link detection in TDT. In both cases, the dependency structure language models perform better than strong baseline approaches.  相似文献   
109.
战略联盟不稳定性的研究现状与展望   总被引:9,自引:0,他引:9  
吴海滨  李垣  谢恩 《科研管理》2004,25(5):46-51
竞争环境的变化使得战略联盟成为企业间合作的一种重要形式,但高达40%—60%的失败率一直是困扰联盟管理的一项难题。本文总结了战略联盟高不稳定性的理论解释和影响因素,并结合学习型联盟与合资企业两种重要的联盟方式探讨了特定联盟形式的不稳定性的特点以及促进联盟稳定的机制设置,在此基础上总结了目前研究的不足和今后研究的方向。  相似文献   
110.
校本培训有着传统培训模式所不具备的优势,是一种新型音乐师资培训模式。尤其是中小学与高师共同协助完成的校本培训在国内还很少。本文通过介绍我国中小学与高师音乐教师校本培训现状、借鉴国外中小学与高师紧密联系的校本培训等内容,阐述了应加强教师全面发展,体现个人价值;在中小学与大学建立伙伴关系;发挥校本培训的组织及保障系统作用;加强校本培训模式建设等几个方面问题,凸显校本培训在我国中小学与高师对接实践中巨大的桥梁作用。  相似文献   
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