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Numerical Minimum Time Control to a Class of Singular Integro-Differential Equations
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作者 Shihchung Chiang 《Journal of Mathematics and System Science》 2015年第2期72-82,共11页
This study presents a numerical method for determining the minimum time required for the states of one class of integro-differential equations of the first kind to reach its attainable region by assuming the forcing t... This study presents a numerical method for determining the minimum time required for the states of one class of integro-differential equations of the first kind to reach its attainable region by assuming the forcing terms of the equations as controls. These equations consist of integro-differential parts containing weakly singular kernels. The feasibility of the numerical method is demonstrated by comparing the minimum time and corresponding possible time by using extreme controls to reach the attainable region under different initial conditions. 展开更多
关键词 Integro-differential equations weakly singular kernels minimum time control
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Dynamic Event-Triggered Mechanisms With Positive Minimum Inter-Event Times for Linear Multiagent Consensus on Directed Graphs
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作者 Sikang Zhan Xianwei Li +1 位作者 Yuanyuan Zou Shaoyuan Li 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期436-450,共15页
This article studies the consensus problem with directed graphs for general linear multi-agent systems.New distributed state-feedback protocols with dynamic event-triggered(DET)mechanisms are proposed for directed gra... This article studies the consensus problem with directed graphs for general linear multi-agent systems.New distributed state-feedback protocols with dynamic event-triggered(DET)mechanisms are proposed for directed graphs that are strongly connected and weight-balanced,general strongly connected,and have spanning trees,respectively.It is proven that strictly positive minimum inter-event times(MIETs)are ensured using the designed DET mechanisms.Several numerical examples are presented to illustrate the effectiveness of the theoretical results.Compared with existing results,our results have the following merits:1)DET mechanisms are designed to determine the sampling instants,which can reduce the communication frequency between agents compared with static mechanisms;2)We focus on the consensus problem on directed graphs,which is more general than existing related results on undirected graphs;3)The existence of positive MIETs is shown to be guaranteed by the designed DET sampling strategies while existing related results can only exclude Zeno behavior. 展开更多
关键词 CONSENSUS directed graphs event-triggered control linear multi-agent systems minimum inter-event times
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Dynamic Event-Triggered Consensus Control for Input Constrained Multi-Agent Systems With a Designable Minimum Inter-Event Time 被引量:4
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作者 Meilin Li Yue Long +2 位作者 Tieshan Li Hongjing Liang C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期649-660,共12页
This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynami... This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach. 展开更多
关键词 Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control
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Minimum Dwell Time for Global Exponential Stability of a Class of Switched Positive Nonlinear Systems 被引量:4
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作者 Ruicheng Ma Shuang An 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期471-477,共7页
This paper will investigate global exponential stability analysis for a class of switched positive nonlinear systems under minimum dwell time switching, whose nonlinear functions for each subsystem are constrained in ... This paper will investigate global exponential stability analysis for a class of switched positive nonlinear systems under minimum dwell time switching, whose nonlinear functions for each subsystem are constrained in a sector field by two odd symmetric piecewise linear functions and whose system matrices for each subsystem are Metzler. A class of multiple time-varying Lyapunov functions is constructed to obtain the computable sufficient conditions on the stability of such switched nonlinear systems within the framework of minimum dwell time switching.All present conditions can be solved by linear/nonlinear programming techniques. An example is provided to demonstrate the effectiveness of the proposed result. 展开更多
关键词 EXPONENTIAL stability linear/nonlinear PROGRAMMING minimum DWELL time SWITCHED NONLINEAR systems
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Determination of the Minimum Testing Time for Wireline Formation Testing with the Finite Element Method
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作者 Hu Falong Xiao Lizhi +1 位作者 Zhang Yuanzhong Wang Chengwei 《Petroleum Science》 SCIE CAS CSCD 2006年第1期39-44,共6页
The wireline formation tester (WFT) is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil a... The wireline formation tester (WFT) is an important tool for formation evaluation, such as calculating the formation pressure and permeability, identifying the fluid type, and determining the interface between oil and water. However, in a low porosity and low permeability formation, the supercharge pressure effect exists, since the mudcake has a poor sealing ability. The mudcake cannot isolate the hydrostatic pressure of the formation around the borehole and the mud seeps into the formations, leading to inaccurate formation pressure measurement. At the same time, the tool can be easily stuck in the low porosity/low permeability formation due to the long waiting and testing time. We present a method for determining the minimum testing time for the wireline formation tester. The pressure distribution of the mudcake and the formation were respectively calculated with the finite element method (FEM). The radius of the influence of mud pressure was also computed, and the minimum testing time in low porosity/low permeability formations was determined within a range of values for different formation permeabilities. The determination of the minimum testing time ensures an accurate formation pressure measurement and minimizes possible accidents due to long waiting and testing time. 展开更多
关键词 Wireline formation tester the minimum testing time the finite element method
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Cognitive MAC Protocol with Minimum Sampling Time and Cross-Layer Cooperation for Low Signal-to-Noise Ratio Environments
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作者 谢显中 胡小峰 +2 位作者 杨和林 马彬 雷维嘉 《China Communications》 SCIE CSCD 2013年第12期125-138,共14页
The previous Decentralised Cognitive Medium Access Control(DC-MAC) protocol allows Secondary Users(SUs) to independently search for spectrum access opportunities without the need for a central coordinator.DC-MAC assum... The previous Decentralised Cognitive Medium Access Control(DC-MAC) protocol allows Secondary Users(SUs) to independently search for spectrum access opportunities without the need for a central coordinator.DC-MAC assumes that the detection scheme is ideal at the Physical(PHY) layer.In fact,a more complex detection algorithm is impractical in distributed spectrum sharing scenarios.Energy Detection(ED) at the PHY layer has become the most common method because of its low computational and implementation complexities.Thus,it is essential to integrate the DC-MAC with ED at the PHY layer.However,ED requires the Minimum Sampling Time(MST)duration to achieve the target detection probability in low Signal-to-Noise Ratio(SNR)environments.Otherwise,it cannot achieve the expected detection performance.In this paper,we derive an accurate expression of MST for ED in low SNR environments.Then,we propose an Optimised DC-MAC(ODC-MAC) protocol which is based on MST,and which amends the aforementioned problems of DC-MAC with ED.Moreover,the closed-form expressions for the unreliable data transmission probability are derived for both DC-MAC and ODC-MAC.We show that the simulation results agree well with the theoretical analyses.The proposed ODC-MAC can improve the data transmission reliability and enhance the throughput compared to the performance of the traditional DC-MAC. 展开更多
关键词 cognitive radio energy detection MAC minimum sampling time the unreliabledata transmission probability THROUGHPUT
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KINEMATIC MINIMUM-TIME TRAJECTORY PLANNING FOR A MANIPULATOR
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作者 叶桦 冯纯伯 《Journal of Southeast University(English Edition)》 EI CAS 1991年第1期85-90,共6页
By using a phase-plane analysis method,the minimum-time trajectory plan-ning problem of a manipulator moving along a given geometric path subject to the con-straints of joint velocities and accelerations is solved in ... By using a phase-plane analysis method,the minimum-time trajectory plan-ning problem of a manipulator moving along a given geometric path subject to the con-straints of joint velocities and accelerations is solved in this paper.The simulation resultfor the first three joints of PUMA-560 is given. 展开更多
关键词 MANIPULATORS TRAJECTORY planning/minimum-time
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三杆张拉整体机器人多绳索协同的驱动策略研究
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作者 张家成 宋自根 《力学季刊》 北大核心 2026年第1期55-65,共11页
张拉整体机器人凭借其轻质、可变形以及优越的结构适应性,在行星探索、灾害救援等领域展现出广阔的应用前景.现有针对张拉整体机器人驱动控制策略的研究中,主要基于最少个数的绳索驱动设计原则.即在机器人驱动控制设计过程中,如果仅收... 张拉整体机器人凭借其轻质、可变形以及优越的结构适应性,在行星探索、灾害救援等领域展现出广阔的应用前景.现有针对张拉整体机器人驱动控制策略的研究中,主要基于最少个数的绳索驱动设计原则.即在机器人驱动控制设计过程中,如果仅收缩单个绳索即可实现运动,则优先收缩该绳索,而不驱动其他绳索.这就导致了因为需要收缩绳索的长度很大,而引起机器人驱动控制的响应时间变长,使得机器人在移动时运动效率低下,限制了其工程应用.为此,本研究以三杆张拉整体机器人为研究对象,基于力密度法,对张拉结构的几何构型与静力平衡特性进行了系统建模,分析了其受力-变形的响应关系.进一步,利用重心偏移的滚动判定方法,设计了遍历搜索算法,提出了基于多绳索协同驱动的控制策略,实现单个绳索收缩量的减小,从而降低机器人在运动变形过程中的结构变形幅度,实现了驱动控制响应时间的显著缩短.最后,研制了基于ESP32控制系统的三杆张拉整体机器人实验平台,并通过原型实验验证了所提出策略的有效性.结果表明,相较于最少驱动绳索运动控制策略,多绳索协同驱动模式能够显著降低变形幅度,减少响应时间. 展开更多
关键词 张拉整体结构 三杆张拉机器人 运动控制 多绳索协同驱动 响应时间
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Remarkable Findings in Fundamental Theory of Quantum Mechanics—Matter Wave and Discrete Time in Physics 被引量:1
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作者 Takahisa Okino 《Journal of Modern Physics》 2022年第2期256-266,共11页
The relation of matter wave, which is well-known as a hypothesis proposed by de Broglie in 1923, gave basis for establishing the quantum mechanics. After that, experimental results revealed that a micro particle has a... The relation of matter wave, which is well-known as a hypothesis proposed by de Broglie in 1923, gave basis for establishing the quantum mechanics. After that, experimental results revealed that a micro particle has a wave nature. However, the theoretical validity of the relation itself has never been revealed since his proposal. Theoretical basis that a micro particle has a wave nature has been thus disregarded in the unsolved state. The diffusion equation having been accepted as Fick’s second law was derived from the theory of Markov process in mathematics. It was then revealed that the diffusivity D depends on an angular momentum of a micro particle in a local space. The fact being unable to discriminate between micro particles in a local space resulted in having to accept the existence of minimum time t<sub>0 </sub>(>0) in the quantum mechanics. Based on t<sub>0</sub> and D obtained here, the theoretical validity of relation of matter wave was confirmed. Denying the density theorem in mathematics for time in physics indicates that the probabilistic interpretation is essentially indispensable for understanding the quantum mechanics. The logical necessity of quantum theory itself is thus understandable through introducing t<sub>0</sub> into the Newton mechanics. It is remarkable that the value of t<sub>0</sub> between 1.14&times;10<sup>-17</sup> s &le; t<sub>0 </sub>&le;1.76×10<sup>-14 </sup>s obtained here is extremely larger than that of the well-known Planck time t<sub>p</sub>=5.396&times;10<sup>-44 </sup>s. 展开更多
关键词 Quantum Diffusion Particle Matter Wave Planck time minimum time
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Interception time and uncertainty optimization for tangent-impulse orbit interception problem
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作者 Yang Hong Li Xin-hong Ding Wen-zhev 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第3期418-440,共23页
The traditional tangent impulse interception problem does not consider the influence of actual deviation.However,by taking the actual state deviation of the interceptor into the orbit design process,an interception or... The traditional tangent impulse interception problem does not consider the influence of actual deviation.However,by taking the actual state deviation of the interceptor into the orbit design process,an interception orbit that is more robust than the nominal orbit can be obtained.Therefore,we study the minimum time interception problem and the minimum terminal interception error problem under tangent impulse conditions and give an orbit optimization method that considers the interception time and the interception uncertainty.First,we express the interceptor's transfer time equation as a form of flight path angle,establish a global optimization model for solving the minimum time tangent impulse interception and give a hybrid optimization algorithm based on Augmented Lagrange Genetic Algorithm-Sequential Quadratic Programming(ALGA-SQP).Secondly,we use the universal time equation and Bootstrap resampling technology to calculate the interceptor's terminal error distribution and establish the relevant global optimization model by using the circumscribed cuboid volume of the interceptor's terminal position error ellipsoid as the optimization index.Finally,we combined the above two singleobjective optimization models to establish a global multi-objective optimization model that considers interception time and interception uncertainty and gave a hybrid multi-objective optimization algorithm based on Non-dominated Sorting Genetic Algorithm Ⅱ-Goal Achievement Method(NSGA2-GAM).The simulation example verifies the effectiveness of this method. 展开更多
关键词 Tangent impulse interception minimum time Interception uncertainty Multi-objective optimization Hybrid optimization
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时序松弛约束下绕障X结构布线算法
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作者 鲁任 朱予涵 刘耿耿 《小型微型计算机系统》 北大核心 2026年第2期495-503,共9页
超大规模集成电路布线结果的优劣将直接影响芯片设计的质量.随着互连延迟逐渐成为芯片延迟的主要来源,在布线过程中进行时序分析变得愈发重要,同时,考虑到障碍在芯片布线中无法避免,以及X结构的引入可以更充分利用布线空间资源,因此,首... 超大规模集成电路布线结果的优劣将直接影响芯片设计的质量.随着互连延迟逐渐成为芯片延迟的主要来源,在布线过程中进行时序分析变得愈发重要,同时,考虑到障碍在芯片布线中无法避免,以及X结构的引入可以更充分利用布线空间资源,因此,首次综合考虑时序松弛、障碍物以及更具互连优势的X结构,提出了一种时序松弛约束下绕障X结构布线算法.首先,为了避免重复地判断引脚间的连线是否经过障碍,提出一种高效的预处理策略,通过构建边障表来记录任意两引脚间的4种布线方式与所有障碍的关系.其次,为了解决构造Steiner最小树这一离散问题,将遗传算法与粒子群优化算法相结合,引入变异算子和交叉算子作为粒子群的离散更新方式.然后,提出了一种局部时序优化策略,通过优化布线半径达到优化最坏负松弛值的目的.接着,提出了一种有效的绕障策略,使布线在不经过障碍的前提下尽可能优化线长.最后,提出了一种路径精炼策略,选择布线资源共享程度最高的布线结构对原有的布线结构进行替换,进而达到优化线长的目标.实验结果表明,所提算法优化了布线的线长以及半径并在时序的关键性指标—最坏负松弛值上比相关算法分别优化了59%、51%和40%,极大提高了电路的稳定性. 展开更多
关键词 超大规模集成电路 Steiner最小树 绕障 X结构布线 时序松弛约束
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放射性气溶胶浓度在线监测响应时间研究
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作者 吴小平 贾文宇 傅甚杰 《环境监控与预警》 2026年第2期61-65,共5页
放射性气溶胶浓度在线监测装置主要用于检验核设施工艺设备的密封效果,并对放射性气溶胶高活度浓度情况进行报警。当前,此类监测装置通常需要较长的响应时间,导致监测数据存在滞后现象。当出现异常工况时,可能导致工作人员的受照射剂量... 放射性气溶胶浓度在线监测装置主要用于检验核设施工艺设备的密封效果,并对放射性气溶胶高活度浓度情况进行报警。当前,此类监测装置通常需要较长的响应时间,导致监测数据存在滞后现象。当出现异常工况时,可能导致工作人员的受照射剂量偏高。为缩短监测响应时间,通过理论推导与数据计算,定量分析了响应时间与放射性气溶胶浓度的探测下限(C_(C))、监测装置的探测效率(η_(t))和取样流量(L)等因素的关系。结果表明,以上3项均是影响响应时间的主要因素。基于此,通过优化关键参数,制定了缩短响应时间的具体措施,并给出了可供参考的参数值(C_(C)可优化为0.05 Bq/m^(3))和设备选型建议。同时,以某次放射性物料泄漏事件为例,评估响应时间优化对工作人员受照射剂量的影响。结果证实,响应时间优化能使工作人员的受照射剂量降低12.5%~78.8%。 展开更多
关键词 放射性气溶胶浓度在线监测 响应时间 探测下限 探测效率 取样效率 取样流量
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隔震结构中最小地震剪力系数合理取值研究
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作者 关洪成 唐曹明 +3 位作者 罗开海 黄世敏 魏明杰 吴乐乐 《结构工程师》 2026年第1期65-74,共10页
为探讨隔震结构设计中最小地震剪力系数的合理取值,采用2自由度简化隔震模型,运用振型分解反应谱法和时程分析法,推导、计算其底部剪重比,与《建筑隔震设计标准》中所规定的最小地震剪力系数限值进行对比,并通过实际工程对最小地震剪力... 为探讨隔震结构设计中最小地震剪力系数的合理取值,采用2自由度简化隔震模型,运用振型分解反应谱法和时程分析法,推导、计算其底部剪重比,与《建筑隔震设计标准》中所规定的最小地震剪力系数限值进行对比,并通过实际工程对最小地震剪力系数取值进行了分析验证。结果表明:[2.0~5.2)s等效周期范围内,上述两种分析方法得出的剪重比均大于《建筑隔震设计标准》中的最小地震剪力系数限值,等效周期在[5.2~6.0]s时小于《建筑隔震设计标准》中限值;在较宽的等效周期范围内,现行《建筑隔震设计标准》中的最小地震剪力系数限值不起控制作用;故建议适当提高《建筑隔震设计标准》中最小地震剪力系数限值,确保结构具有一定的抗震安全性。 展开更多
关键词 隔震结构 最小地震剪力系数 振型分解反应谱法 时程分析法 等效周期
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实时频谱分析仪全捕获最小脉宽幅度比校准方法探究
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作者 姜琳 于文婷 +2 位作者 刘群 赵航 葛笑佳 《科技创新与应用》 2026年第6期160-162,166,共4页
在使用实时频谱分析仪检测信号时,检测到的信号会出现突发变化、跳频这一时变特性。频谱分析仪目前在部队检定规程是使用GJB 8805—2015《宽频带频谱分析仪检定规程》,该规程主要针对扫频式频谱分析仪和矢量信号分析仪,无法对频谱分析... 在使用实时频谱分析仪检测信号时,检测到的信号会出现突发变化、跳频这一时变特性。频谱分析仪目前在部队检定规程是使用GJB 8805—2015《宽频带频谱分析仪检定规程》,该规程主要针对扫频式频谱分析仪和矢量信号分析仪,无法对频谱分析仪的实时性加以计量。实时频谱分析仪能测量时变这个特点,可以对其全捕获最小脉宽幅度比这个参数进行测量,该文针对其校准方法进行实验验证和不确定度分析与评定。 展开更多
关键词 实时频谱分析仪 全捕获最小脉宽幅度比 射频技术 脉冲宽度 信号
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Joint DOA and time delay estimation method for space-time coherent distributed signals based on search 被引量:1
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作者 Qian Bin Yang Wanlin Wan Qun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第2期341-346,共6页
Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on m... Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on multipath distribution function is given after new space and time manifold is reconstructed. Then joint spacetime signal subspace is obtained by converting acquired channel from time domain to frequency domain .Then space and time spectrum is formulated by the space sub-matrix and time sub-matrix taken out of joint space-time signal subspace, and parameters are estimated by searching the minimum eigenvalues of the space matrix and the time matrix. Lastly, A space and time parameters matching process is performed by using the orthogonal property between joint noise subspace and the space-time manifold. In contrast with tradition MUSIC, the algorithm we present here only need two 1- dimension searching and was not sensitive to different distribution function. 展开更多
关键词 Space-time coherent distribution DOA Relative time delay minimum eigenvalue.
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Finite-Time Stability and Stabilization of Discrete-Time Switching Markov Jump Linear System
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作者 JIN Yunyun SONG Yang +1 位作者 LIU Yongzhuang HOU Weiyan 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第5期674-680,共7页
Switching Markov jump linear system(SMJLS),a special hybrid system,has attracted a lot of studies recently.SMJLS is governed by stochastic and deterministic commutations.This paper focuses on the switching strategy wh... Switching Markov jump linear system(SMJLS),a special hybrid system,has attracted a lot of studies recently.SMJLS is governed by stochastic and deterministic commutations.This paper focuses on the switching strategy which stabilizes the SMJLS in a finite time interval in order to further expand the existing results and investigate new aspects of such systems.Several sufficient conditions for finite-time stability of discrete-time SMJLS are provided,and the numerical problems in these sufficient conditions are solved by solving linear matrix inequalities(LMIs).Finally,numerical examples are given to show the feasibility and effectiveness of the results. 展开更多
关键词 switching Markov jump linear system(SMJLS) finite-time stability stochastic switching deterministic switching minimum dwell time
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Time-optimal Trajectories for a Car-like Robot 被引量:1
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作者 WANG Hui-Fang CHEN Yang-Zhou 《自动化学报》 EI CSCD 北大核心 2008年第4期445-452,共8页
这份报纸为完成时间最佳的轨道的足够的家庭在基于几何最佳的控制理论歧管的 3-dimensional 连接机器人的任何二种配置提供一个新几何方法。我们为分析非线性的问题的这种特殊类型提供一个新观点。从 Pontryagin 的最小的原则(PMP ) 和... 这份报纸为完成时间最佳的轨道的足够的家庭在基于几何最佳的控制理论歧管的 3-dimensional 连接机器人的任何二种配置提供一个新几何方法。我们为分析非线性的问题的这种特殊类型提供一个新观点。从 Pontryagin 的最小的原则(PMP ) 和谎言代数学基于切换的功能和他们的衍生物的结构的特征,我们造一个特殊坐标系统并且介绍新向量。我们发现在这新向量的旋转轨道和最佳的控制轨道之间的一对一的印射。而且,我们定义表示位置和这向量的旋转方向的切换的向量,并且得出一个结论规定起始、最后的切换的向量能特别地决定一条最佳的轨道。另外,它是能直接被使用选择一条时间最佳的轨道的一个条件被提供的第一次。 展开更多
关键词 汽车 机器人 最优化设计 自动化系统
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Estimation of Fading Statistics of Nakagami Channel with Weibull Distributed Tolerable Outage Time
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作者 Anjana Jain Prakash D. Vyavahare Leeladhar Arya 《Wireless Engineering and Technology》 2012年第2期77-82,共6页
Characterization of a mobile radio channel plays an important role in designing a reliable wireless communication system. Such channels are analyzed by two state model, namely satisfactory and outage state. This paper... Characterization of a mobile radio channel plays an important role in designing a reliable wireless communication system. Such channels are analyzed by two state model, namely satisfactory and outage state. This paper presents the analysis to estimate fading parameters of wireless channel with omission of certain outage durations which are considered as “Tolerance time”. Minimum outage duration which can be tolerated by a wireless fading channel to achieve desired packet error rate is defined as tolerance time. Normally a system with tolerable minimum outage time is analyzed based on Fade Duration Distribution (FDD) function over Rayleigh channel. In this paper Weibull function is used as FDD for varying tolerance time. The approach is simple and in general applicable from Rayleigh to Nakagami channels. The analysis is extended to study the effect of Tolerance time on channel fading statistics such as Average Fade Duration (AFD) and frequency of outage. Further the effects of various fade margin and Doppler spread on fading parameters are also investigated. The analysis can also be used in case of timeout expiration, connection resetting and congestion window control. 展开更多
关键词 Fading Statistics Tolerance time FADE Duration Distribution FUNCTION Weibull FUNCTION NAKAGAMI Wireless CHANNEL minimum OUTAGE time
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Calculation Method and Analysis of Blockage Time of Cluster Munitions Against Runway
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作者 黄寒砚 王正明 王菖 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第3期234-240,共7页
The blockage probability and the blockage time are two important indexes for assessing the blockage efficiency of cluster munitions against the runway. The improved region-by-region searching method and the random sam... The blockage probability and the blockage time are two important indexes for assessing the blockage efficiency of cluster munitions against the runway. The improved region-by-region searching method and the random sampling method are proposed to calculate the blockage time by considering the minimum number of craters which need to be repaired after attack. A minimum leave window (MLW) with the minimum number of craters is found out as a region to be repaired,the blockage probability and the blockage time are calculated by the two methods in which the impact points of the sub-munitions are generated with Monte-Carlo simulation technique. An example is given to show the reasonableness of the two methods under the conditions of adequacy simulating times and enough sampling times,and how to choose the methods in application. 展开更多
关键词 时间分析 计算方法 跑道 淤塞 弹药 集束 蒙特卡罗方法 模拟技术
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Receding horizon H_∞ control for discrete-time Markovian jump linear systems
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作者 Jiwei Wen Fei Liu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期292-299,共8页
Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given qua... Receding horizon H∞ control scheme which can deal with both the H∞ disturbance attenuation and mean square stability is proposed for a class of discrete-time Markovian jump linear systems when minimizing a given quadratic performance criteria. First, a control law is established for jump systems based on pontryagin’s minimum principle and it can be constructed through numerical solution of iterative equations. The aim of this control strategy is to obtain an optimal control which can minimize the cost function under the worst disturbance at every sampling time. Due to the difficulty of the assurance of stability, then the above mentioned approach is improved by determining terminal weighting matrix which satisfies cost monotonicity condition. The control move which is calculated by using this type of terminal weighting matrix as boundary condition naturally guarantees the mean square stability of the closed-loop system. A sufficient condition for the existence of the terminal weighting matrix is presented in linear matrix inequality (LMI) form which can be solved efficiently by available software toolbox. Finally, a numerical example is given to illustrate the feasibility and effectiveness of the proposed method. 展开更多
关键词 Marker jump linear systems receding horizon H∞ control mean square stability terminal weighting matrix pontrya-gin's minimum principle current time jump mode.
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