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1.
2019年国际篮联篮球世界杯在中国圆满举行,广州作为分赛场,承接了西班牙、波多黎各、突尼斯以及伊朗四支代表队的小组比赛6场。通过对广州赛区四支队伍在小组赛中的表现技术进行分析,并对比中国队在本次赛事中的表现,发现中国男篮在备赛与参赛阶段,存在大赛目标不清晰,心理训练与细节训练不足,教练团队执教水平不稳定,篮球基本功不扎实等一系列问题,反映出我国篮球的发展正处于困境。系统地分析广州小组赛中四支队伍的赛况,并与中国队做出对比,有针对性地提出建议,为中国篮球的发展提供参考。 相似文献
2.
周嘉豪 《河北体育学院学报》2020,34(2):1-5
运用文献资料法和逻辑分析法,从非均衡国家治理角度对我国职业足球改革面临的困境进行研究。通过梳理相关文献提出,当前国家治理模式具有非均衡性,存在各主体参与失范、治理权责分配失衡的问题,市场、社会、个人主体话语权较弱、参与性不足,形成了较强的政府依赖路径。对职业足球改革各主体之间的关系进行阐述,认为政府和足协是改革话语权的掌握者和资源的分配者,其他主体参与改革作用较小。指出,尚未明确职业足球的发展动机、足协组织能力与管理效能不足、各主体缺乏有效联系与合作是非均衡国家治理模式的具体表现;政府的非市场手段治理、市场失灵与第三部门失灵、个体意识与自我治理不足是其深层次原因。在此基础上提出相应的发展对策。 相似文献
3.
In this paper, the optimal synchronization controller design problem for complex dynamical networks with unknown system internal dynamics is studied. A necessary and sufficient condition on the existence of the optimal control minimizing a quadratic performance index is given. The optimal control law consists of a feedback control and a compensated feedforward control, and the feedback control gain can be obtained by solving the well-known Algebraic Riccati Equation (ARE). Especially, in the presence of unknown system dynamics, a novel adaptive iterative algorithm using the information of system states and inputs is proposed to solve the ARE to get the optimal feedback control gain. Finally, a simulation example shows the effectiveness of the theoretical results. 相似文献
4.
In this paper, the synchronization problem of fractional-order neural networks (FNNs) with chaotic dynamics is investigated via the intermittent control strategy. Two types of intermittent control methods, the aperiodic one and the periodic one, are applied to achieve the synchronization of the considered systems. Based on the dynamic characteristics of the intermittent control systems, the piecewise Lyapunov function method is employed to derive the synchronization criteria with less conservatism. The results under the aperiodically intermittent control show more generality than the ones via the periodically intermittent control. For each of the aperiodic and periodic cases, a simple controller design process is presented to show how to design the corresponding intermittent controller. Finally, two numerical examples are provided to demonstrate the effectiveness of the obtained theoretical results. 相似文献
5.
This paper focuses on the problem of semi-global output-feedback stabilization for a class of switched nonlinear time-delay systems in strict-feedback form. A switched state observer is first constructed, then switched linear output-feedback controllers for individual subsystems are designed. By skillfully constructing multiple Lyapunov–Krasovskii functionals and successfully solving several troublesome obstacles, such as time-varying delay and switching signals and nonlinearity in the design procedure, the switched linear output-feedback controllers designed can render the resulting closed-loop switched system semi-globally stabilizable under a class of switching signals with average dwell time. Furthermore, under some milder conditions on nonlinearities, the semi-global output-feedback stabilization problem for switched nonlinear time-delay systems is also studied. Simulation studies on two examples, which include a continuous stirred tank reactor, are carried out to demonstrate the effectiveness of the proposed approach. 相似文献
6.
This article presents a multi-lagged-input based data-driven adaptive iterative learning control (M-DDAILC) method for nonlinear multiple-input-multiple-output (MIMO) systems by virtue of multi-lagged-input iterative dynamic linearization (IDL). The original nonlinear and non-affine MIMO system is equivalently transformed into a linear input-output incremental counterpart without loss of dynamics. The proposed learning law utilizes the desired trajectory to cancel the influence from iteration-by-iteration variations, as well as additional multi-lagged inputs to improve control performance. The developed iterative estimation law is more effective and also makes estimation of the unknown parameters easier because the dynamics for each parameter to represent are decreased by dividing the system into multiple components in the multi-lagged-input IDL formulation. Moreover, the proposed M-DDAILC does not need an explicit and accurate model. It is proved to be iteratively convergent with rigorous analysis. Both a numerical example and a practical application to a permanent magnet linear motor are provided to verify the validity and applicability of the proposed method. 相似文献
7.
Qun Liu Daqing Jiang Tasawar Hayat Ahmed Alsaedi 《Journal of The Franklin Institute》2019,356(5):2960-2993
In this paper, we consider a stochastic multigroup SIQR epidemic model with standard incidence rates. By using the stochastic Lyapunov function method, we establish sufficient conditions for the existence of a stationary distribution of the positive solutions to the model. Then we establish sufficient conditions for extinction of the diseases. A stationary distribution means that all the individuals can be coexistent and persistent in the long term. Finally, some examples and numerical simulations are introduced to illustrate our theoretical results. 相似文献
8.
Jennifer Catharine Evans Hennie Yip Kannass Chan Christine Armatas Ada Tse 《高等教育研究与发展》2020,39(4):643-656
ABSTRACTOnline learning has become a ubiquitous part of the educational landscape and how teachers are supported in developing approaches to teaching online is a fundamental aspect of the students’ learning experience. Based on the implementation of a professional development course on becoming an online teacher offered in a blended learning mode at one university in Hong Kong, this article proposes that offering this type of professional development in a blended mode is very effective in facilitating enhanced usage of the university’s learning management system. In a blended mode, teachers are actively engaged with blended learning and were found to make more extensive use of features/tools in Blackboard after they attended the professional development course. Results support that offering professional development in a blended mode provides teachers with an authentic student perspective, at the same time as they take guided steps in the teacher’s role in blended learning. 相似文献
9.
沈竹雅 《体育科技文献通报》2020,(2):33-33,47
在对高职学生就业能力的内涵进行简要阐述的基础上,重点论述体育参与对高职学生就业能力的促进作用:体育参与有利于提升高职学生的职业身体素质,有利于提升高职学生的应聘抗挫能力,有利于培养高职学生的团结协作能力。最后,就如何激发高职学生的体育参与积极性简要提出若干建议。 相似文献
10.
为进一步实现CUBA与CBA联赛新时期改革计划,疏通我国篮球后备人才战略培养路径,以“新时期”CUBA与CBA的人才衔接与培育为研究对象,运用文献资料、录像观察、数理统计等方法,对CBA联赛选秀球员进行综合分析。研究结果表明:1)存在问题包括组织机构衔接不畅、选秀球员竞技水平不精、人才培养观契合度不高及俱乐部注意程度不足4个方面。2)改善路径包括逐渐推进多元主体衔接度及流畅性、全面优化高校球员竞技能力及水平、消除人才培养僵化及保守化、扎实提升俱乐部关注程度及积极性。 相似文献