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1.
文化功能也就是"出之于人,归之于人",江口土家族"金钱杆"起于秦末时期的西楚霸王,形于族人生产生活实践中。经过研究发现,"金钱杆"是具有彰显土家族文化的独特符号、"常"与"非常"之间转换的独特节点、教化孩童的重要载体以及增强体质的独特途径的少数民族传统体育活动。本研究主要探求"金钱杆"发展逻辑,旨在为"金钱杆"的传承和发展提供有益的指导。  相似文献   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
基于江西省几所地方高校创新创业教育的实地调查数据,运用有序 Probit 模型解读创新创业教育背景下可能影响地方高校科技创新服务功能的指数因子;对江西省地方高校创新创业教育在区域科技创新系统中的地位与作用进行了分析,指出建立良好的约束和激励机制能达到引导地方高校自觉实施创新创业教育的目的,更充分发挥地方高校科技创新服务功能。研究表明地方高校实施创新创业教育不仅可提高地方高校科技创新能力和综合实力,更能有效促进区域内高校和谐发展。  相似文献   
8.
Handwriter identification aims to simplify the task of forensic experts by providing them with semi-automated tools in order to enable them to narrow down the search to determine the final identification of an unknown handwritten sample. An identification algorithm aims to produce a list of predicted writers of the unknown handwritten sample ranked in terms of confidence measure metrics for use by the forensic expert will make the final decision.Most existing handwriter identification systems use either statistical or model-based approaches. To further improve the performances this paper proposes to deploy a combination of both approaches using Oriented Basic Image features and the concept of graphemes codebook. To reduce the resulting high dimensionality of the feature vector a Kernel Principal Component Analysis has been used. To gauge the effectiveness of the proposed method a performance analysis, using IAM dataset for English handwriting and ICFHR 2012 dataset for Arabic handwriting, has been carried out. The results obtained achieved an accuracy of 96% thus demonstrating its superiority when compared against similar techniques.  相似文献   
9.
运用中国知网(CNKI)检索库进行检索,共查找到期刊文献115篇,其中国内期刊65篇,硕士论文31篇。通过Cite Space和中国知网(CNKI)文献分析功能,对国内身体功能训练研究进行计量学分析。研究的基本特征表现为:研究机构多,文献期刊发表数量较少,核心期刊占比较少,论文质量与数量之间存在差异。研究热点以身体功能训练为主,并突显了“功能训练”“训练”和“体育工作者”等关键词,作者合作比较少,仅形成数个微小的作者合作网络。  相似文献   
10.
传统武术在我国有着悠久的历史,是我国优秀的传统文化,集强身健体、技击防卫、娱乐观赏等价值功能于一体。“一带一路”倡议的提出对传统武术在现今社会中的价值和功能产生了新的影响。文章运用文献资料法、逻辑分析法等研究方法,从“一带一路”倡议对传统武术产生的影响、“一带一路”倡议下传统武术的当代价值、“一带一路”倡议下传统武术的当代功能三个方面进行深度分析,探究“一带一路”倡议下传统武术的当代价值与功能。  相似文献   
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