共查询到20条相似文献，搜索用时 31 毫秒
1.
This paper studies bounded input bounded output (BIBO) stability for a class of neutral systems with time-varying delays. Based on Lyapunov method and linear matrix inequalities, some new BIBO stability criteria are established. The numerical simulation is made to demonstrate the effectiveness of the theoretical results obtained in this paper. 相似文献
2.
《Journal of The Franklin Institute》2022,359(1):84-103
In this paper, the problems of stochastic finite-time stability and stabilization of discrete-time positive Markov jump systems are investigated. To deal with time-varying delays and switching transition probability (STP), stochastic finite-time stability conditions are established under mode-dependent average dwell time (MDADT) switching signal by developing a stochastic copositive Lyapunov-Krasovskii functional approach. Then a dual-mode dependent output feedback controller is designed, thus stochastic finite-time stabilization is achieved based on linear programming technique. Finally, two examples are given to show the effectiveness of our results. 相似文献
3.
客观评估知识供应链效率状态,有利于促进区域高技术产业持续健康发展。借鉴知识供应链理论、DEA模型和聚类分析法,构建了一套较为系统的区域高技术产业知识供应链效率的分类评价体系;以中国高技术产业统计年鉴(2013-2014年)的相关数据为基础,从投入产出两个维度,给出了我国31省市区域高技术产业知识供应链效率的分类评估结果和优化对策。研究表明:我国高技术产业知识供应链效率总体较好,不同类型省市的知识供应链的投入产出规模差距悬殊;消除投入资源浪费,提升有效发明专利数和新产品销售收入,是相对落后省市改进高技术产业知识供应链效率的主要着力点。本研究成果为我国不同类别省市优化高技术产业知识供应链效率提供了实践启示。 相似文献
4.
《Journal of The Franklin Institute》2023,360(2):1005-1035
There are many hybrid stochastic differential equations (SDEs) in the real-world that don’t satisfy the linear growth condition (namely, SDEs are highly nonlinear), but they have highly nonlinear characteristics. Based on some existing results, the main difficulties here are to deal with those equations if they are driven by Lévy noise and delay terms, then to investigate their stability in this case. The present paper aims to show how to stabilize a given unstable nonlinear hybrid SDEs with Lévy noise by designing delay feedback controls in the both drift and diffusion parts of the given SDEs. The controllers are based on discrete-time state observations which are more realistic and make the cost less in practice. By using the Lyapunov functional method under a set of appropriate assumptions, stability results of the controlled hybrid SDEs are discussed in the sense of pth moment asymptotic stability and exponential stability. As an application, an illustrative example is provided to show the feasibility of our theorem. The results obtained in this paper can be considered as an extension of some conclusions in the stabilization theory. 相似文献
5.
《Journal of The Franklin Institute》2022,359(10):4893-4914
This paper investigates the global stabilization of discrete-time linear systems with input time delay by bounded controls. Based on some special canonical forms containing time delays both in its input and state, two special discrete-time linear systems---multiple integrators and oscillators are first considered. The global stabilizing controllers are respectively established, and moreover, explicit conditions are established to guarantee the stability of the closed-loop systems. Subsequently, a concise design method is proposed for globally stabilizing general discrete-time linear system by combining the design methods for multiple integrators and oscillators. The designed controller is in the explicit form with explicit stability conditions being given, and thus is easier to use than the existing results. Finally, numerical simulations illustrate the effectiveness of the proposed approaches. 相似文献
6.
具有输入时滞的关联不确定大系统的分散鲁棒控制 总被引：4，自引：0，他引：4
研究了一类同时具有输入时滞以及不确定参数的关联大系统的稳定性问题.基于所谓的还原法,给出一种新的状态反馈控制器的设计方法,这种方法的不同之处在于利用了时延的大小以及反馈控制的历史信息.根据Lyapunov稳定性理论得到了系统在控制器作用下稳定的充分条件,所有条件都化成可解的标准线性矩阵不等式(LMIs)形式.最后给出了一个数值例子,说明结果的可行性,并和一般无记忆的控制器相比较,说明建立的控制器有着更好的性能. 相似文献
7.
In this paper, we develop a matrix-based methodology to investigate the problems of stability and stabilizability for a deterministic finite automaton (DFA) in the framework of the semi-tensor product (STP) of matrices. First, we discuss the equilibrium point stability (resp., set stability) of a DFA, i.e., verifying whether or not all state trajectories starting from a subset of states converge to a specified equilibrium point (resp., subset of states). The necessary and sufficient conditions for verifying both stabilities are given, respectively. Second, equilibrium point stabilizability (resp., set stabilizability) of a DFA is investigated as verifying the issue of whether or not a DFA can be globally or locally stabilized to a specified equilibrium point (resp., subset of states) by a permissible state-feedback controller. Based on the pre-reachability set and invariant-subset defined in this paper, the matrix-based criteria for verifying equilibrium point stabilizability and set stabilizability are derived, respectively. Furthermore, for each type of stabilizability, all permissible state-feedback controllers for the case of minimal length state trajectories, called optimal state-feedback controllers, are characterized by using the proposed polynomial algorithms. Finally, two examples are presented to illustrate the effectiveness of the theoretical results. 相似文献
8.
This paper is concerned with the stability and stabilization for systems with two additive time-varying input delays arising from networked control systems. A new Lyapunov functional is constructed and a tighter upper bound of the derivative of the Lyapunov functional is derived by applying a convex polyhedron method. The resulting stability criteria are of fewer matrix variables and less conservative than some existing ones. Based on the stability criteria, a state feedback controller is designed such that the closed-loop system is asymptotically stable. Numerical examples are given to show the less conservatism of the stability criteria and the effectiveness of the designed method. 相似文献
9.
This paper concerns the exponential synchronization problem of stochastic complex networks with multiple weights (SCNMW). By the method of network split, SCNMW can be modelled as stochastic coupled systems driven by Brownian motion. By combining graph theory, Lyapunov stability theory and state feedback control technique, drive-response synchronization criteria of SCNMW have been obtained. Two kinds of exponential synchronization criteria are obtained, one is given with Lyapunov functions of vertex systems, and the other is shown with the coefficients of SCNMW. The obtained synchronization principles are closely related to the coupling strength of multiple sub-networks and the intensity of noise perturbation. Finally, a numerical example with some simulations is presented to illustrate the theoretical results. 相似文献
10.
In this paper, the stability problem of discrete-time systems with time-varying delay is considered. Some new stability criteria are derived by using a switching technique. Compared with the Lyapunov–Krasovskii functional (LKF) approach, the method used in this paper has two features. First, a switched model, which is equivalent to the original system and contains more delay information, is introduced. It means that the criteria obtained by using the LKF method can be regarded as stability criteria for the switched system under arbitrary switching. Second, when the switching signal is known, the stability problem for the switched model under constrained switching is considered and piecewise LKFs are adopted to obtain stability criteria. Since constrained switching is less conservative than arbitrary switching if the switching signal is known, one can know that the obtained results in this paper are less conservative than some existing ones. Two examples are given to illustrate the effectiveness of the obtained results. 相似文献
11.
《Journal of The Franklin Institute》2023,360(7):4572-4596
The purpose of this paper is to present a comprehensive study of a coherent feedback network where the main component consists of two distant double quantum dot (DQD) qubits which are directly coupled to a cavity. This main component has recently been physically realized (van Woerkom et al., Microwave photon-mediated interactions between semiconductor qubits, Physical Review X, 8(4):041018, 2018). The feedback loop is closed by cascading this main component with a beamsplitter. The dynamics of this coherent feedback network is studied from three perspectives. First, an analytic form of the output single-photon state of the network driven by a single-photon state is derived. In contrast to the experimental observations made in the above paper where a laser is used as input, new interesting physical phenomena are revealed by means of single-photon input. Second, excitation probabilities of DQD qubits are computed when the network is driven by a single-photon input state. Finally, if the input is vacuum but one of the two DQD qubits is initialized in its excited state, the explicit expression of the steady-state joint system-field state is derived, which shows that the output single-photon field and the two DQD qubits can form an entangled state if the transition frequencies of two DQD qubits are equal. This analytical expression can be used to interpret experimental results in the existing literature. 相似文献
12.
收入差距问题是目前社会的热点问题,也是学术界一直关注的焦点问题.基于一项针对某行业科技人员的大规模调查数据,对科技人员收入差距问题展开研究,结果如下:(1)通过基尼系数发现,垄断行业内科技人员收入相对平均.(2)最优尺度回归表明,人力资本、岗位特征对于科技人员收入差距具有显著性影响,但工作绩效对于科技人员平均月工资收入没有影响,地域对于科技人员收入差距影响最大,其次是工作层级,接下来才是职称等人力资本因素.(3)多重对应分析直观的显示出人力资本与岗位特征在科技人员收入上具有交互作用. 相似文献
13.
This paper investigates the problem of robust stability for neutral type system with mixed delays and time-varying structured uncertainties. Based on Lyapunov stability theory and linear matrix inequalities (LMIs) method, some new stability criteria are presented. The difference between this paper and other existing results is that the lower bounds and upper bounds of the neutral-delay and discrete-delay are considered, which will obtain some less conservative stability analysis results. Several numerical examples are given to demonstrate the effectiveness and merit of the proposed results. 相似文献
14.
针对中国省域科技发展水平的综合评价问题,本文在分析现有研究存在的不足及问题的基础上,首先,对科技评价指标体系的构建原则进行了分析,并构建了一套用于评价省域科技发展水平的评价指标体系;其次,提出了一种双重驱动的中国省域科技发展水平评价方法,从“功能驱动”和“差异驱动”两个角度对中国省域的科技发展水平进行评价,“功能驱动”用于衡量省域科技发展的能力,“差异驱动”用于衡量省域科技发展的均衡程度,并针对“差异驱动”构建了一种新的客观赋权方法。最后,根据构建的指标体系和评价方法对2016年中国31个省域的科技发展水平进行了评价和分析,结果表明,科技发展水平发展最好的是北京、上海和广东,最差的是西藏、内蒙古和青海,且中国省域间的科技发展水平差距较大,但各省域自身的发展均较为均衡,并未出现某些省域过度强调某些指标发展的现象。 相似文献
15.
科技强国是现代化强国的核心要义，科技现代化是中国式现代化的重要内容。把握新发展阶段、贯彻新发展理念、构建新发展格局，推动高质量发展，迫切需要从战略体系视角，在社会主义现代化强国建设全局中系统推进新时代科技强国建设，具体包含：（1）界定科技强国战略内涵，建立“战略环境-战略目标-战略能力-战略行动”战略体系分析框架；（2）分析科技强国建设战略环境，准确研判长远发展大势，牢牢把握科技战略机遇；（3）丰富科技强国建设战略目标，进入创新型国家行列和前列，建成世界科技强国；（4）提升科技强国建设战略能力，建设国家创新体系，强化国家战略科技力量和国家战略人才力量；（5）深入推进科技强国建设战略行动，全面实施创新驱动发展战略，实现高水平科技自立自强。 相似文献
16.
《Journal of The Franklin Institute》2019,356(16):9689-9712
This paper deals with the input–output finite-time stabilization problem for Markovian jump systems (MJSs) with incompletely known transition rates. An observer-based output feedback controller is constructed to study the input–output finite-time stability (IO-FTS) problem. By using the mode-dependent Lyapunov–krasovskii functional method, a sufficient criterion checking the IO-FTS problem is provided. Then, an observer and a corresponding state feedback controller for the individual subsystem are respectively designed to solve the input–output finite-time stabilization problem for the systems. Finally, a numerical example on the mass-spring system model is investigated to bring out the advantages of the control scheme proposed in this paper. 相似文献
17.
《Journal of The Franklin Institute》2022,359(8):3749-3767
This paper investigates practical stability problem for nonlinear impulsive stochastic delayed systems driven by G-Brownian motion (IGSDSs). Practical stability can describe quantitative properties and qualitative behavior in contrast to traditional Lyapunov stability theory. Based on G-Lyapunov function, Razumikhin-type theorem, G-Itô formula, Burkholder–Davis–Gundy (B-D-G) inequalities I & II and stochastic analysis technique, some new criteria for moment and quasi sure global practical uniform exponential stability of IGSDSs are proposed. Finally, two examples are presented to verify validity of our theoretical results. 相似文献
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19.
针对中国高技术产业面临的创新驱动发展的可持续转型增长的问题与挑战以及知识积累隐性研发创新与绩效非直接关联的特征,从地区知识积累视角改进并构建自主研发创新驱动科技绩效的非线性动态门槛模型,探讨地区知识积累的动态门槛效应和时空异质性,在方法和内容上揭示创新驱动发展面临的挑战形势中的"黑箱"。研究表明:高技术产业研发人员投入显著促进产业科技绩效的提升;技术引进与改造创新均在一定程度上对科技绩效产生负向效应;高技术产业自主研发创新驱动科技绩效的效应显著受限于地区知识积累水平的影响,随着知识积累门槛水平提升,自主研发创新驱动效益逐渐提高,存在基于知识积累水平的双门槛效应,进而划分低知识积累(KS≤5.285)、中知识积累(5.285KS≤6.769)和高知识积累(KS6.769)三种类型。同时,自主研发创新驱动机理存在地区知识积累水平的时空异质性,不同年份地区间的分布差异较大。 相似文献
20.
In this paper, the adaptive bilinear control of a first-order 1-D hyperbolic partial differential equation (PDE) with an unknown time-varying source term is investigated where only boundary measurements are available. By means of boundary injection, the bilinear adaptive law is developed in the Lyapunov approach. It consists of a state observer and an input adaptation law combined with a bilinear control method derived using an energy-like principle. Both global asymptotic practical convergence of the tracking error and input-to-state stability of the system are guaranteed. A potential application of this control strategy is the one-loop solar collector parabolic trough where the solar irradiance is the unknown input (source term) and the flow rate is the control variable. The objective is to drive the boundary temperature at the outlet to track a desired profile. Simulation results are provided to illustrate the performance of the proposed method. 相似文献