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991.
篮球文化作为一种在篮球运动实践中创造的物质和精神财富,通过影响大学生的精神品味、道德观念、运动技术、技能与智能等,可以有效地培养大学生健康的社会兴趣,准确接纳与传递社会信息的能力,逐渐形成健康的生活风格,对于不断提高大学生的人际交往能力和适应内外生活环境的能力具有重要的现实意义.  相似文献   
992.
大学篮球是我国竞技篮球运动开展的重要阵地,尽管我国大学篮球联赛的竞技水平不高,但一直被当作我国的篮球人才库。采用文献资料等方法,对我国高校篮球运动员的培养现状和存在的问题进行研究,旨在为我国篮球运动的发展提供参考。研究表明:与美国大学篮球联赛相比,我国大学篮球联赛的影响力较小,培养出的人才也凤毛麟角。知名高校所起作用较小、社会重视程度不高、后勤保障不足、缺乏优秀篮球苗子和教练员整体水平较低是我国高校难以成为CBA人才库的重要原因。  相似文献   
993.
[摘要]为了解湖南省篮球传统校运动队的建设情况,对参加2011年湖南省中学生篮球比赛的21支球队进行了调查研究,结果表明各队均坚持常年训练和参加省市两级的中学生篮球比赛,但每年参加的比赛偏少,水平不高。影响其发展的主要原因是队伍构成不尽合理、学训矛盾突出和经费投入严重不足。建议制订针对性的发展规划,加强教练员和运动员的培养力度,加大经费投入力度以促进篮球传统校运动队的发展。  相似文献   
994.
运用文献资料、录像观察、数理统计、逻辑分析等研究方法,探讨了中国女篮在第30届伦敦奥运会上2分球、3分球、快攻、内、外线进攻能力、前场篮板球、助攻、进攻失误、二次机会得分的优势和不足。通过研究分析,归纳出中国女篮的进攻能力问题,提出相应的对策与建议。  相似文献   
995.
老子的哲学思想为现代企业管理提供了有益借鉴.在现代企业管理中,"无为"是为了达到"无不为"-大有作为;"不争"-不为一己私欲争夺计较,才能争得为企业中心服务的最大成功;诚信应成为企业管理的基础;注意细节,才能做精做细,才能真正体现管理的作用和价值.  相似文献   
996.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
997.
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   
998.
This paper investigates the passivity and synchronization problems for two classes of multiple weighted coupled neural networks (MWCNNs) with or without time delays. Firstly, by utilizing an impulsive control strategy and some inequality techniques, several passivity criteria for MWCNNs with diverse dimensions of output and input are established. Then, based on the Lyapunov functional, some sufficient conditions to ensure the synchronization of MWCNNs via impulsive control are derived. In addition, combined with the comparison principle and the impulsive delay differential inequality, the global exponential synchronization of MWCNNs with time-varying delays is considered under impulsive control. Finally, two numerical examples illustrate the effectiveness of the obtained results.  相似文献   
999.
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   
1000.
Gas flow has fractional order dynamics; therefore, it is reasonable to assume that the pneumatic systems with a proportional valve to regulate gas flow have fractional order dynamics as well. There is a hypothesis that the fractional order control has better control performance for this inherent fractional order system, although the model used for fractional controller design is integer order. To test this hypothesis, a fractional order sliding mode controller is proposed to control the pneumatic position servo system, which is based on the exponential reaching law. In this method, the fractional order derivative is introduced into the sliding mode surface. The stability of the controller is proven using Lyapunov theorem. Since the pressure sensor is not required, the control system configuration is simple and inexpensive. The experimental results presented indicate the proposed method has better control performance than the fractional order proportional integral derivative (FPID) controller and some conventional integral order control methods. Points to be noticed here are that the fractional order sliding mode control is superior to the integral order sliding mode counterpart, and the FPID is superior to the corresponding integral order PID, both with optimal parameters. Among all the methods compared, the proposed method achieves the highest tracking accuracy. Moreover, the proposed controller has less chattering in the manipulated variable, the energy consumption of the controller is therefore substantially reduced.  相似文献   
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