欧洲足球不同年龄层国家队成绩的相关性分析     

赵柏林  袁柏青 《当代体育科技》2020,(11):241-241,243

根据对世界四大足球赛的数据分析,发现欧洲国家青年队的成绩与国家队成绩的相关性比较小,其直接表现为欧洲国家往往在世界杯表现优越,而在低级别的青年队和少年队的表现却不如南美和非洲国家,究其原因,欧洲国家凭借着出色的青训系统,培养和归化了大量的海外人才,欧洲大多数国家支持双重国籍,欧洲一体化能真正落实到资源共享,所以欧洲国家青年队成绩比不上南美和非洲,但国家队却能优势明显。  相似文献   

北京冬奥会筹备对运动休闲基地建设的示范作用研究     

李杰桃 《广州体育学院学报》2020,(3):43-45

北京冬奥会雪上项目将在张家口市崇礼区进行，冬奥会筹备工作的重点也就集中在了这个过去名不见经传的小镇上了。虽然距冬奥会开幕还有近2年的时间，但崇礼区作为滑雪运动圣地已蜚声海内外，国外专业滑雪运动队将它作为训练基地外，国内业余滑雪运动者也从全国各地涌向这里。如今，张家口市整个经济被冬奥会激活了，其产业结构也已因崇礼区滑雪运动休闲基地实现了从农业经济向资源旅游经济的转型。虽然冬奥会筹备是国家级的大事，但张家口崇礼区的建设筹备仍然对全国休闲运动基地建设具有示范指导意义。  相似文献   

Optimal synchronization controller design for complex dynamical networks with unknown system dynamics     

Ya-Wei Cao  Guang-Hong Yang  Xiao-Jian Li 《Journal of The Franklin Institute》2019,356(12):6071-6086

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   

Intermittent control strategy for synchronization of fractional-order neural networks via piecewise Lyapunov function method     

Ying Yang  Yong He  Min Wu 《Journal of The Franklin Institute》2019,356(8):4648-4676

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   

Linear output-feedback-based semi-global stabilization for switched nonlinear time-delay systems     

Zhenhua Li  Lijun Long  Jun Zhao 《Journal of The Franklin Institute》2019,356(13):7224-7245

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   

Systems model and individual simulations of training strategies in elite short-track speed skaters     

Thibaut Méline  Ludovic Mathieu  Fabio Borrani  Robin Candau 《Journal of sports sciences》2019,37(3):347-355

This study aimed to evaluate the effect of simulated training strategies on performance potential in elite short-track speed skaters. Training load and field-based criterion performances from fifteen athletes (10 males, 5 females) were collected over a 3-month training period and the relationship between training loads and performance was computed with a variable dose-response model using a genetic algorithm. Individual simulations of tapers preceded or not preceded by an overload training (OT) were assessed. We obtained a significant correlation between actual and modelled performances (R² = 0.76 ± 0.07). Regarding model parameters, no significant difference was found between males and females but the time to recover performance tended to be lower in females. Simulations in which the taper parameters were free highlighted that an exponential or a step taper were the most effective for increasing performance compared to a linear taper (p < 0.05). Optimal exponential taper duration after OT was 10.7 ± 2.4d and the optimal load reduction was 75.9 ± 3.7%. OT intensity had the greatest influence on the predicted performance, followed by OT duration, taper decay, and to a lesser extent load reduction during taper and taper duration. Thus, a variable dose-response systems model allows the evaluation of different taper strategies and their potential effect on performance changes.  相似文献   

Multi-lagged-input iterative dynamic linearization based data-driven adaptive iterative learning control     

Na Lin  Ronghu Chi  Biao Huang  Zhongsheng Hou 《Journal of The Franklin Institute》2019,356(1):457-473

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   

Dynamics of a stochastic multigroup SIQR epidemic model with standard incidence rates     

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   

权利抑或特权：奥运会参赛权法律性质辨析——平昌冬奥会俄罗斯运动员及辅助人员体育仲裁案例述评     

郭树理 《上海体育学院学报》2020,(1):39-48

俄罗斯国家奥委会遭国际奥委会(IOC)暂停成员资格,导致很多无辜运动员无法参加平昌冬奥会,国际体育仲裁院(CAS)平昌冬奥会特别仲裁机构处理的数起案件均涉及俄罗斯运动员的参赛资格问题。俄罗斯运动员在仲裁程序中败诉的主要原因是《奥林匹克宪章》规定:奥运会是IOC的专属财产、任何人不拥有参加奥运会的所谓权利、IOC可以拒绝任何人参赛而无须出具理由。IOC运用对奥运会的专属权利,无正当合理理由拒绝符合参赛条件的俄罗斯清白运动员参赛,有构成垄断的嫌疑。符合参赛选拔条件、且不存在禁止性限制因素(如兴奋剂禁赛处罚在身)的清白运动员参加奥运会,是他们的权利,而不是IOC赋予他们的特权。切实保护运动员参赛权利是各国法院和国际体育仲裁院在处理体育参赛资格案件中的一贯立场,平昌冬奥会仲裁庭的实践过于保守。奥林匹克运动体育善治的改革,要求必须对《奥林匹克宪章》进行修改,最大限度地保护运动员的参赛权利,实现《运动员权利与义务宣言》的宗旨。  相似文献   

北京2022年冬奥会和冬残奥会遗产价值及其评估研究     

徐拥军  张丹  闫静 《武汉体育学院学报》2020,54(10):15-22

北京2022年冬奥会和冬残奥会遗产是中国对奥林匹克运动许下的新愿景，这一愿景具体在《北京2022年冬奥会和冬残奥会遗产战略计划》的7项遗产、35项内容之中得以体现，它们既是对未来遗产的多元创造，也是对既有遗产的夏冬延续。根据历届OGI报告、奥组委官方政策文本与"一续二全三跨"原则，确定北京2022年冬奥会和冬残奥会遗产的评估要求，并以定量与定性结合分析法、KPIs、风险评估法、成本效益分析法为指引，打造一个凝聚新理念、汇聚新模式、融合新方法的奥运遗产价值评估的"北京方案"。  相似文献