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1.
In this paper, the path planning problem for an unicycle-like mobile robot is considered. By using some results borrowed from algebraic geometry, a technique is given to determine a dynamical system that is affine in the input and whose trajectories tend to a chosen algebraic set independently of the control input. Since this does not guarantee that the corresponding paths of motion are collision free, an optimal control problem is formulated to enforce this behavior, and its approximate solution is determined via integral reinforcement learning. Finally, it is shown how such results can be used to derive a feedback control law for unicycle-like mobile robots.  相似文献   
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文章结合指导大学生创新训练计划项目的多年实践,从项目申报与创新型人才选拔、项目实施过程中的教与学以及本科生创新能力的提升三个方面剖析了开展大学生创新训练计划项目对本科生创新型人才培养的重要作用,旨在为全面提升高等院校本科生人才培养质量、推行创新型本科人才培养模式提供理论和实践参考。  相似文献   
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关汉卿的杂剧《望江亭中秋切鲙》现有4个版本传世。其中,《古杂剧》明代顾曲斋刻本与臧懋循编《元曲选》明万历年刻本在曲牌、曲辞、宾白等内容上存在较大差异,语言风格也不甚相同。《古杂剧》本是《望江亭》明刻本中制作较为精良的上乘之作,而《元曲选》本是后世最为流行的元杂剧选集。臧懋循在选编《元曲选》的过程中对元杂剧剧本的改动是造成二者文本差异的主要原因。  相似文献   
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基础物理作为民族预科教育中重要的一门通识教育课程,无论是在教学内容还是在教学方法上都需要改革创新。基于近年来基础物理的教学实践,新疆大学基础物理教学团队探索出了一种基于预科生学习现状以“问题解决”为导向的教学方法,在全面提升少数民族预科生科学素养、探索精神和创新能力等方面都发挥了积极的作用。  相似文献   
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This paper is concerned with the finite-time and fixed-time synchronization of complex networks with discontinuous nodes dynamics. Firstly, under the framework of Filippov solution, a new theorem of finite-time and fixed-time stability is established for nonlinear systems with discontinuous right-hand sides by using mainly reduction to absurdity. Furthermore, for a class of discontinuous complex networks, a general control law is firstly designed. Under the unified control framework and the same conditions, the considered networks are ensured to achieve finite-time or fixed-time synchronization by only adjusting the value of a key control parameter. Based on the similar discussion, a unified control strategy is also provided to realize respectively asymptotical, exponential and finite-time synchronization of the addressed networks. Finally, the derived theoretical results are supported by an example with numerical simulations.  相似文献   
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The exponential stabilization of BAM reaction-diffusion neural networks with mixed delays is discussed in this article. At first, a general pinning impulsive controller is introduced, in which the control functions are nonlinear and the pinning neurons are determined by reordering the state error. Next, based on the designed control protocol and the Lyapunov–Krasovskii functional approach, some novel and useful criteria, which depend on the diffusion coefficients and controlling parameters, are established to guarantee the global exponential stabilization of the considered neural networks. Finally, the effectiveness of the proposed control strategy is shown by two numerical examples.  相似文献   
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This paper deals with the output consensus problem for uncertain nonstrict-feedback leader-follower multi-agent systems with predefined performance. A distributed event-triggered control strategy with dynamic threshold is proposed to update the actual control input and alleviate the computation burden of the communication procedure effectively. The unknown nonstrict-feedback structures are addressed by using the property of radial basis function neural networks. It is worth noting that in practical applications, the predefined performance often alternates between constrained and unconstrained cases in some extreme situations. To overcome this challenge, a novel coordinate transformation technique is incorporated to tackle both the two cases with and without performance constraint in a unified manner. As a result, the proposed event-triggered control approach ensures that the output consensus errors converge to zero asymptotically, and all the signals in the closed-loop system are bounded. Finally, the effectiveness of the proposed protocol is demonstrated by the simulation results.  相似文献   
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基于肇东市义务教育均衡发展迎国检的具体实践,以肇东市义务教育校际均衡发展为研究对象,采用文献法、调查问卷、访谈法等研究方法,对肇东市义务教育校际均衡发展情况开展研究,梳理了肇东市义务教育均衡发展现状,从而发现了在部分政策制定方面相对比较滞后、重点学校和一般学校之间存在差异、师资力量上存在一定差距、资源配置仍需进一步加强、不均衡发展导致择校现象等方面问题,进一步分析出这些问题的影响因素,提供了五点可行性建议,主要包括:增强政府的主体责任、持续加大教育经费投入力度、持续提升教师队伍素质、推进网络平台共享提升教育质量、改变学生家长盲目的择校观念等。  相似文献   
10.
This paper investigates the stability and stabilizability of complex-valued memristive neural networks (CVMNNs) with random time-varying delays via non-fragile sampled-data control. Taking the influence of gain fluctuations into account, a non-fragile sampled-data controller is designed for CVMNNs. Compared with the existing control schemes, the one here is more applicable and can effectively save the communication resources. The assumption on activation functions of CVMNNs is relaxed by only needing the complex-valued activation functions satisfying the Lipschitz condition. By constructing a suitable Lyapunov–Krasovskii functional (LKF), new stability and stabilizability criteria are derived for CVMNNs. Different from the existing results with the maximum absolute values of memristive connection weights, our ones are based on the average values of the maximum and minimum of the memristive connection weights. Finally, numerical simulations are given to validate the effectiveness of the theoretical results.  相似文献   
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