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1.
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
2.
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
3.
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
4.
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
5.
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
6.
摘要:我国高等体育教育资源优化配置研究引入社会学视角理论与方法,理论与实践均取得专家的认同。运用文献资料法、专家访谈法和实地考察法等方法发现,在计划经济体制下我国高等体育教育资源配置主体单一性、手段行政化和政治倾向性强,凸显出高等体育教育资源配置缺乏激励机制和市场竞争机制的问题,造成高等体育教育资源配置成本最大化和社会效应的最小化问题较多。自改革开放以来,随着我国市场经济体制的建立为高等体育教育资源优化配置提供了难得的发展机遇,我国高等体育教育资源配置取得了明显成效,但仍然存在高等体育教育资源配置机制滞后、体制机制改革创新步伐缓慢、高等体育教育资源配置不合理以及民办普通高校体育教育资源配置严重不足等问题。据此,从社会学研究的视角,提出了构建多主体推动高等体育教育资源优化配置创新的发展模式、多元化高等体育教育资源优化配置资金投入的保障体系、高等体育教育资源优化配置均衡发展的运行机制和大学城体育教育资源“共建共享”的创新发展模式的新时代我国高等体育教育资源优化配置的发展策略,旨在服务新时代全民健身与全民健康深度融合发展,“推动构建人类命运共同体”发展目标的实现。 相似文献
7.
8.
曹卫东 《北京体育大学学报》2019,42(1):17-22
摘要:新时代是我国发展新的历史方位,体育强国、教育强国、健康中国三大战略为世界一流体育大学提出了新的更高要求。为此,北京体育大学提出了“三个转型”综合改革,以推进世界一流体育大学建设和高水平竞技体育后备人才培养基地建设,为国家培养勇担新时代体育事业发展重任的优秀人才。为实现上述目标,应在深刻认识“三个转型”改革提出的背景基础上,深入理解“三个转型”的内涵与目标,全面推进“三个转型”综合改革,为新时代体育、教育事业贡献北京体育大学的力量。研究背景包括:1)新时代是“三个转型”的历史坐标,2)强国战略是“三个转型”的现实依据,3)创新模式是“三个转型”的客观需要;“三个转型”分别是:1)全面推进从传统经验型体育大学向现代科技型体育大学转型,2)从以夏季项目为主的体育大学向夏季冬季项目全面发展的体育大学转型,3)从本土化体育大学向国际化体育大学转型,其目的是实现两大办学目标:1)把北京体育大学建成中国高水平竞技体育后备人才培养基地,2)把北京体育大学建设成为世界一流体育大学;为了实现“三个转型”转型及其目标,必须准确把握“办大学与建基地、文化传承与科技创新、立足中国与放眼世界”三个维度及其核心关键问题。 相似文献
9.
Sophie Rutter Verena Blinzler Chaoyu Ye Max L. Wilson Michael D. Twidale 《Information processing & management》2019,56(3):919-938
With greater access to computational resources, people use search to address many everyday challenges in their lives, including solving technology problems. Although there are now many useful ‘how-to’ resources online (especially videos on YouTube), it can still be difficult to identify, understand, and resolve certain kinds of technical problem. While research tasks have been studied for many years and we know the tactics people use, we know far less about searchers’ tactics for how-to technical tasks that involve actually being able to apply found information to resolve a problem. Crucial to our study was developing and studying a highly realistic, how-to technical task, for which there was no single guidance resource: making a phone safe for a child. After providing 39 participants with an actual phone to fix, and a search engine to perform the task, we analysed their search tactics using retrospective cued think aloud interviews. Our primary contribution is a set of 77 tactics used, in three categories, along with detail of how common they were. We conclude that people had a lot of tactics in their repertoire. Although it was not hard for participants to find relevant information, what was hard was for participants to find information they could use; indeed only 23% of participants successfully completed the entire task. Domain knowledge affected the choice of tactics used (although not necessarily towards better task success). We discuss these influences and make design recommendations for how future search systems can support those in resolving how-to technical tasks. 相似文献
10.
Xiang-Gui Guo Hong-Jian Li Jun-Jie Zhao Wei-Wei Che 《Journal of The Franklin Institute》2019,356(9):4842-4858
This paper investigates the expected static group synchronization problem of the second-order multi-agent systems via pinning control. For directed communication topology with spanning tree, based on Gershgorin disk theorem and the matrix property, a static pinning control protocol with fixed gains is first introduced and some sufficient and necessary static group synchronization criteria are also established. It is worth mentioning that a rigorous proof is also given that only one pinning node is needed to guarantee static group synchronization, which could be inferred that our protocol might be more economical and effective in large scale of multi-agent systems. Then, for weakly connected directed communication topology with nodes of zero in-degree, an adaptive pinning control applied to the node with zero in-degree is also proposed to achieve static group synchronization. Finally, the efficiency of the proposed protocols is verified by two simulation examples. 相似文献