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A novel adaptive finite-time controller for synchronizing chaotic gyros with nonlinear inputs 被引量:1
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作者 Mohammad Pourmahmood Aghababa 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期86-91,共6页
In this paper, the problem of the finite-time synchronization of two uncertain chaotic gyros is discussed. The parameters of both the master and the slave gyros are assumed to be unknown in advance. The effects of mod... In this paper, the problem of the finite-time synchronization of two uncertain chaotic gyros is discussed. The parameters of both the master and the slave gyros are assumed to be unknown in advance. The effects of model uncertainties and input nonlinearities are also taken into account. An appropriate adaptation law is proposed to tackle the gyros' unknown parameters. Based on the adaptation law and the finite-time control technique, proper control laws are introduced to ensure that the trajectories of the slave gyro converge to the trajectories of the master gyro in a given finite time. Simulation results show the applicability and the efficiency of the proposed finite-time controller. 展开更多
关键词 chaotic gyro finite-time synchronization model uncertainty nonlinear input
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Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer 被引量:1
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作者 Chi Ma Dianbiao Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1039-1050,共12页
This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eli... This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm. 展开更多
关键词 finite-time control multi-agent systems neural network prescribed performance control time-varying formation control
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Controlling chaos in permanent magnet synchronous motor based on finite-time stability theory 被引量:15
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作者 韦笃取 张波 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第4期1399-1403,共5页
This paper reports that the performance of permanent magnet synchronous motor (PMSM) degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in PMSM, a nonlinear... This paper reports that the performance of permanent magnet synchronous motor (PMSM) degrades due to chaos when its systemic parameters fall into a certain area. To control the undesirable chaos in PMSM, a nonlinear controller, which is simple and easy to be constructed, is presented to achieve finite-time chaos control based on the finite-time stability theory. Computer simulation results show that the proposed controller is very effective. The obtained results may help to maintain the industrial servo driven system's security operation. 展开更多
关键词 chaos control finite-time stability theory permanent magnet synchronous motor
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A finite-time fuzzy adaptive output-feedback fault-tolerant control for underactuated wheeled mobile robots systems 被引量:1
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作者 Pingfan Liu Shaocheng Tong 《Journal of Automation and Intelligence》 2024年第2期111-118,共8页
This paper investigates the adaptive fuzzy finite-time output-feedback fault-tolerant control (FTC) problemfor a class of nonlinear underactuated wheeled mobile robots (UWMRs) system with intermittent actuatorfaults. ... This paper investigates the adaptive fuzzy finite-time output-feedback fault-tolerant control (FTC) problemfor a class of nonlinear underactuated wheeled mobile robots (UWMRs) system with intermittent actuatorfaults. The UWMR system includes unknown nonlinear dynamics and immeasurable states. Fuzzy logic systems(FLSs) are utilized to work out immeasurable functions. Furthermore, with the support of the backsteppingcontrol technique and adaptive fuzzy state observer, a fuzzy adaptive finite-time output-feedback FTC scheme isdeveloped under the intermittent actuator faults. It is testifying the scheme can ensure the controlled nonlinearUWMRs is stable and the estimation errors are convergent. Finally, the comparison results and simulationvalidate the effectiveness of the proposed fuzzy adaptive finite-time FTC approach. 展开更多
关键词 Underactuated wheeled mobile robots system finite-time Fuzzy adaptive fault-tolerant control OUTPUT-FEEDBACK Intermittent actuator faults
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Finite-Time Synchronization for Heterogeneous Complex Networks with Time-Varying Delays 被引量:1
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作者 Yicong Ma Yali Tai 《Applied Mathematics》 2020年第10期1000-1012,共13页
This paper studies the problem of finite-time synchronization for a class of heterogeneous complex networks which not only have node time-varying delays and coupled time-varying delays but also contain uncertain distu... This paper studies the problem of finite-time synchronization for a class of heterogeneous complex networks which not only have node time-varying delays and coupled time-varying delays but also contain uncertain disturbance. An appropriate controller is designed such that this type of network can be synchronized within a finite time. By constructing a proper Lyapunov function and using the finite-time stability theory, the sufficient conditions for the network to achieve finite-time synchronization are given and the finite time is estimated. Finally, the conclusions obtained are extended to the case of homogeneous complex networks with time-varying delays and uncertain disturbance. 展开更多
关键词 finite-time synchronization HETEROGENEOUS Time-Varying Delays Uncertain Disturbance
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Finite-Time Synchronization of Fractional-Order Chaotic Systems with Different Structures under Stochastic Disturbances 被引量:1
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作者 Weiqiu Pan Tianzeng Li 《Journal of Computer and Communications》 2021年第6期120-137,共18页
This paper studies the finite-time synchronization of fractional-order chaotic systems with different structures under parameter disturbance and external disturbance. We put forward a fractional-order controller that ... This paper studies the finite-time synchronization of fractional-order chaotic systems with different structures under parameter disturbance and external disturbance. We put forward a fractional-order controller that can achieve the finite-time synchronization of any-order fractional-order chaotic systems under stochastic disturbances. This controller has good robustness and anti-interference performance. With the concept of the finite-time stability theory given, some judgment criterions for the synchronization of fractional-order chaotic systems are proved. This method can not only make the error systems have a faster convergence rate but also can be implemented in engineering easily. The numerical simulations of two specific examples demonstrate the effectiveness of the method. At the same time, the synchronised time of finite-time synchronization is shorter and faster than the complete synchronization and the time can be adjusted according to the parameters in the controller. 展开更多
关键词 Fractional Order CHAOS finite-time synchronization Stochastic Disturbance
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Fault-tolerant finite-time dynamical consensus of double-integrator multi-agent systems with partial agents subject to synchronous self-sensing function failure 被引量:1
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作者 Zhi-Hai Wu Lin-Bo Xie 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第12期719-725,共7页
This paper investigates fault-tolerant finite-time dynamical consensus problems of double-integrator multi-agent systems(MASs)with partial agents subject to synchronous self-sensing function failure(SSFF).A strategy o... This paper investigates fault-tolerant finite-time dynamical consensus problems of double-integrator multi-agent systems(MASs)with partial agents subject to synchronous self-sensing function failure(SSFF).A strategy of recovering the connectivity of network topology among normal agents based on multi-hop communication and a fault-tolerant finitetime dynamical consensus protocol with time-varying gains are proposed to resist synchronous SSFF.It is proved that double-integrator MASs with partial agents subject to synchronous SSFF using the proposed strategy of network topology connectivity recovery and fault-tolerant finite-time dynamical consensus protocol with the proper time-varying gains can achieve finite-time dynamical consensus.Numerical simulations are given to illustrate the effectiveness of the theoretical results. 展开更多
关键词 multi-agent systems synchronous self-sensing function failure finite-time dynamical consensus network topology connectivity recovery
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Hyperbolic Tangent Function-Based Protocols for Global/Semi-Global Finite-Time Consensus of Multi-Agent Systems
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作者 Zongyu Zuo Jingchuan Tang +1 位作者 Ruiqi Ke Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1381-1397,共17页
This paper investigates the problem of global/semi-global finite-time consensus for integrator-type multi-agent sys-tems.New hyperbolic tangent function-based protocols are pro-posed to achieve global and semi-global ... This paper investigates the problem of global/semi-global finite-time consensus for integrator-type multi-agent sys-tems.New hyperbolic tangent function-based protocols are pro-posed to achieve global and semi-global finite-time consensus for both single-integrator and double-integrator multi-agent systems with leaderless undirected and leader-following directed commu-nication topologies.These new protocols not only provide an explicit upper-bound estimate for the settling time,but also have a user-prescribed bounded control level.In addition,compared to some existing results based on the saturation function,the pro-posed approach considerably simplifies the protocol design and the stability analysis.Illustrative examples and an application demonstrate the effectiveness of the proposed protocols. 展开更多
关键词 Consensus protocol finite-time consensus hyper-bolic tangent function multi-agent systems.
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Finite-Time Stabilization for Constrained Discrete-time Systems by Using Model Predictive Control
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作者 Bing Zhu Xiaozhuoer Yuan +1 位作者 Li Dai Zhiwen Qiang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1656-1666,共11页
In this paper, a model predictive control(MPC)framework is proposed for finite-time stabilization of linear and nonlinear discrete-time systems subject to state and control constraints. The proposed MPC framework guar... In this paper, a model predictive control(MPC)framework is proposed for finite-time stabilization of linear and nonlinear discrete-time systems subject to state and control constraints. The proposed MPC framework guarantees the finite-time convergence property by assigning the control horizon equal to the dimension of the overall system, and only penalizing the terminal cost in the optimization, where the stage costs are not penalized explicitly. A terminal inequality constraint is added to guarantee the feasibility and stability of the closed-loop system.Initial feasibility can be improved via augmentation. The finite-time convergence of the proposed MPC is proved theoretically,and is supported by simulation examples. 展开更多
关键词 CONSTRAINTS deadbeat control finite-time stabilization model predictive control(MPC)
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Robust Finite-time Synchronization of Non-identical Fractional-order Hyperchaotic Systems and Its Application in Secure Communication 被引量:5
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作者 Hadi Delavari Milad Mohadeszadeh 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期228-235,共8页
This paper proposes a novel adaptive sliding mode control(SMC) method for synchronization of non-identical fractional-order(FO) chaotic and hyper-chaotic systems. Under the existence of system uncertainties and extern... This paper proposes a novel adaptive sliding mode control(SMC) method for synchronization of non-identical fractional-order(FO) chaotic and hyper-chaotic systems. Under the existence of system uncertainties and external disturbances,finite-time synchronization between two FO chaotic and hyperchaotic systems is achieved by introducing a novel adaptive sliding mode controller(ASMC). Here in this paper, a fractional sliding surface is proposed. A stability criterion for FO nonlinear dynamic systems is introduced. Sufficient conditions to guarantee stable synchronization are given in the sense of the Lyapunov stability theorem. To tackle the uncertainties and external disturbances, appropriate adaptation laws are introduced. Particle swarm optimization(PSO) is used for estimating the controller parameters. Finally, finite-time synchronization of the FO chaotic and hyper-chaotic systems is applied to secure communication. 展开更多
关键词 Adaptive SLIDING mode control (ASMC) CHAOS synchronization FRACTIONAL order (FO) hyper-chaotic system LYAPUNOV THEOREM SECURE communication
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Finite-time decentralized event-triggered state estimation for coupled neural networks under unreliable Markovian network against mixed cyberattacks
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作者 Xiulin Wang Youzhi Cai Feng Li 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期175-183,共9页
This article investigates the issue of finite-time state estimation in coupled neural networks under random mixed cyberattacks,in which the Markov process is used to model the mixed cyberattacks.To optimize the utiliz... This article investigates the issue of finite-time state estimation in coupled neural networks under random mixed cyberattacks,in which the Markov process is used to model the mixed cyberattacks.To optimize the utilization of channel resources,a decentralized event-triggered mechanism is adopted during the information transmission.By establishing the augmentation system and constructing the Lyapunov function,sufficient conditions are obtained for the system to be finite-time bounded and satisfy the H_(∞ )performance index.Then,under these conditions,a suitable state estimator gain is obtained.Finally,the feasibility of the method is verified by a given illustrative example. 展开更多
关键词 Markov jump systems coupled neural networks decentralized event-triggered mechanism finite-time state estimation
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Prescribed finite-time stabilization of fuzzy neural networks with time-varying controller
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作者 Yufeng Zhou Yawen Zhou Peng Wan 《Journal of Automation and Intelligence》 2024年第3期176-184,共9页
This paper investigates the exponential and prescribed finite-time stabilization with time-varying controller.First,the constraints of boundedness and differentiability on time delays are simultaneously relaxed,the Li... This paper investigates the exponential and prescribed finite-time stabilization with time-varying controller.First,the constraints of boundedness and differentiability on time delays are simultaneously relaxed,the Lipschitz condition for activation function is also relaxed.Second,different from the traditional Lyapunov function,two different time-varying Lyapunov functions are respectively constructed to achieve the exponential and prescribed finite-time stabilization.Significantly,the exponential convergence rate and the settling time are constants that can be given in advance and are not affected by system parameters and initial states.In addition,the time-varying controllers have good tolerance for disturbance caused by discontinuous functions and the disturbance is perfectly resolved and does not affect the control performance.Especially,the form of controllers is relatively simple and there is not necessary to design the fractional-order controllers for prescribed finite-time stabilization.Furthermore,the exponential and prescribed finite-time stabilization for FNNs without delay are respectively established via continuous time-varying state feedback control.Finally,examples show the effectiveness of the proposed control methods. 展开更多
关键词 Fuzzy neural networks Exponential stabilization Prescribed finite-time stabilization Time delay Discontinuous activation
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Finite-time synchronization of uncertain fractional-order multi-weighted complex networks with external disturbances via adaptive quantized control
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作者 Hongwei Zhang Ran Cheng Dawei Ding 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第10期341-351,共11页
The finite-time synchronization of fractional-order multi-weighted complex networks(FMCNs)with uncertain parameters and external disturbances is studied.Firstly,based on fractional calculus characteristics and Lyapuno... The finite-time synchronization of fractional-order multi-weighted complex networks(FMCNs)with uncertain parameters and external disturbances is studied.Firstly,based on fractional calculus characteristics and Lyapunov stability theory,quantized controllers are designed to guarantee that FMCNs can achieve synchronization in a limited time with and without coupling delay,respectively.Then,appropriate parameter update laws are obtained to identify the uncertain parameters in FMCNs.Finally,numerical simulation examples are given to validate the correctness of the theoretical results. 展开更多
关键词 fractional-order complex networks uncertain parameter finite-time synchronization quantized control
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Distributed dynamic event-based finite-time dissipative synchronization control for semi-Markov switched fuzzy cyber-physical systems against random packet losses
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作者 伍锡如 张煜翀 +1 位作者 张畑畑 张斌磊 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期328-342,共15页
This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzz... This paper is concerned with the finite-time dissipative synchronization control problem of semi-Markov switched cyber-physical systems in the presence of packet losses, which is constructed by the Takagi–Sugeno fuzzy model. To save the network communication burden, a distributed dynamic event-triggered mechanism is developed to restrain the information update. Besides, random packet dropouts following the Bernoulli distribution are assumed to occur in sensor to controller channels, where the triggered control input is analyzed via an equivalent method containing a new stochastic variable. By establishing the mode-dependent Lyapunov–Krasovskii functional with augmented terms, the finite-time boundness of the error system limited to strict dissipativity is studied. As a result of the help of an extended reciprocally convex matrix inequality technique, less conservative criteria in terms of linear matrix inequalities are deduced to calculate the desired control gains. Finally, two examples in regard to practical systems are provided to display the effectiveness of the proposed theory. 展开更多
关键词 cyber-physical systems finite-time synchronization distributed dynamic event-triggered mechanism random packet losses
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Dynamic modeling and aperiodically intermittent strategy for adaptive finite-time synchronization control of the multi-weighted complex transportation networks with multiple delays
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作者 Ning Li Haiyi Sun +1 位作者 Xin Jing Zhongtang Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期184-193,共10页
The idea of network splitting according to time delay and weight is introduced.Based on the cyber physical systems(CPS),a class of multi-weighted complex transportation networks with multiple delays is modeled.The fin... The idea of network splitting according to time delay and weight is introduced.Based on the cyber physical systems(CPS),a class of multi-weighted complex transportation networks with multiple delays is modeled.The finite-time synchronization of the proposed complex transportation networks model is studied systematically.On the basis of the theory of stability,the technique of adaptive control,aperiodically intermittent control and finite-time control,the aperiodically intermittent adaptive finite-time synchronization controller is designed.The controller designed in this paper is beneficial for understanding the synchronization in multi-weighted complex transportation networks with multiple delays.In addition,the conditions for the existence of finite time synchronization have been discussed in detail.And the specific value of the settling finite time for synchronization is obtained.Moreover,the outer coupling configuration matrices are not required to be irreducible or symmetric.Finally,simulation results of the finite-time synchronization problem are given to illustrate the correctness of the results obtained. 展开更多
关键词 complex transportation networks adaptive finite-time synchronization multiple delays and multi-weighted aperiodically intermittent control
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Finite-time complex projective synchronization of fractional-order complex-valued uncertain multi-link network and its image encryption application
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作者 Yong-Bing Hu Xiao-Min Yang +1 位作者 Da-Wei Ding Zong-Li Yang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期244-255,共12页
Multi-link networks are universal in the real world such as relationship networks,transportation networks,and communication networks.It is significant to investigate the synchronization of the network with multi-link.... Multi-link networks are universal in the real world such as relationship networks,transportation networks,and communication networks.It is significant to investigate the synchronization of the network with multi-link.In this paper,considering the complex network with uncertain parameters,new adaptive controller and update laws are proposed to ensure that complex-valued multilink network realizes finite-time complex projective synchronization(FTCPS).In addition,based on fractional-order Lyapunov functional method and finite-time stability theory,the criteria of FTCPS are derived and synchronization time is given which is associated with fractional order and control parameters.Meanwhile,numerical example is given to verify the validity of proposed finite-time complex projection strategy and analyze the relationship between synchronization time and fractional order and control parameters.Finally,the network is applied to image encryption,and the security analysis is carried out to verify the correctness of this method. 展开更多
关键词 multi-links network fractional order complex-valued network finite-time complex projective synchronization image encryption
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Finite-time Mittag-Leffler synchronization of fractional-order complex-valued memristive neural networks with time delay
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作者 Guan Wang Zhixia Ding +2 位作者 Sai Li Le Yang Rui Jiao 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第10期297-306,共10页
Without dividing the complex-valued systems into two real-valued ones, a class of fractional-order complex-valued memristive neural networks(FCVMNNs) with time delay is investigated. Firstly, based on the complex-valu... Without dividing the complex-valued systems into two real-valued ones, a class of fractional-order complex-valued memristive neural networks(FCVMNNs) with time delay is investigated. Firstly, based on the complex-valued sign function, a novel complex-valued feedback controller is devised to research such systems. Under the framework of Filippov solution, differential inclusion theory and Lyapunov stability theorem, the finite-time Mittag-Leffler synchronization(FTMLS) of FCVMNNs with time delay can be realized. Meanwhile, the upper bound of the synchronization settling time(SST) is less conservative than previous results. In addition, by adjusting controller parameters, the global asymptotic synchronization of FCVMNNs with time delay can also be realized, which improves and enrich some existing results. Lastly,some simulation examples are designed to verify the validity of conclusions. 展开更多
关键词 finite-time Mittag-Leffler synchronization fractional-order complex-valued memristive neural networks time delay
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Finite-time sliding mode synchronization of chaotic systems
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作者 倪骏康 刘崇新 +1 位作者 刘凯 刘凌 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期80-86,共7页
A new finite-time sliding mode control approach is presented for synchronizing two different topological structure chaotic systems. With the help of the Lyapunov method, the convergence property of the proposed contro... A new finite-time sliding mode control approach is presented for synchronizing two different topological structure chaotic systems. With the help of the Lyapunov method, the convergence property of the proposed control strategy is discussed in a rigorous manner. Furthermore, it is mathematically proved that our control strategy has a faster convergence speed than the conventional finite-time sliding mode control scheme. In addition, the proposed control strategy can ensure the finite-time synchronization between the master and the slave chaotic systems under internal uncertainties and external disturbances. Simulation results are provided to show the speediness and robustness of the proposed scheme. It is worth noticing that the proposed control scheme is applicable for secure communications. 展开更多
关键词 finite-time control sliding mode control chaos synchronization secure communication
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Design of an adaptive finite-time controller for synchronization of two identical/different non-autonomous chaotic flywheel governor systems
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作者 Mohammad Pourmahmood Aghababa 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期101-111,共11页
The centrifugal flywheel governor (CFG) is a mechanical device that automatically controls the speed of an engine and avoids the damage caused by sudden change of load torque. It has been shown that this system exhi... The centrifugal flywheel governor (CFG) is a mechanical device that automatically controls the speed of an engine and avoids the damage caused by sudden change of load torque. It has been shown that this system exhibits very rich and complex dynamics such as chaos. This paper investigates the problem of robust finite-time synchronization of non-autonomous chaotic CFGs. The effects of unknown parameters, model uncertainties and external disturbances are fully taken into account. First, it is assumed that the parameters of both master and slave CFGs have the same value and a suitable adaptive finite-time controller is designed. Second, two CFGs are synchronized with the parameters of different values via a robust adaptive finite-time control approach. Finally, some numerical simulations are used to demonstrate the effectiveness and robustness of the proposed finite-time controllers. 展开更多
关键词 finite-time controller chaos synchronization non-autonomous centrifugal flywheel gov-ernor chaotic system
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Fixed-Time and Finite-Time Synchronization for a Class of Output-Coupling Complex Networks via Continuous Control
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作者 Zhiwei Li 《International Journal of Communications, Network and System Sciences》 2019年第10期151-169,共19页
This paper mainly investigates the finite-time and fixed-time synchronization problem for a class of general output-coupling complex networks with output feedback nodes. The fixed-time and finite-time synchronization ... This paper mainly investigates the finite-time and fixed-time synchronization problem for a class of general output-coupling complex networks with output feedback nodes. The fixed-time and finite-time synchronization protocols are presented based on continuous controller strategies which can efficaciously eliminate chattering phenomenon existing in some previous results. Several sufficient conditions ensuring fixed-time and finite-time synchronization are derived by employing Lyapunov stability theory, linear matrix inequality (LMI) and adaptive technique. Furthermore, aimed at the model of this article, we study the problem of adaptive coupling strength in fixed-time synchronization which is rarely involved in previous results. Finally, several numerical examples are given to illustrate the effectiveness of our results. 展开更多
关键词 Output-Coupling Complex Networks Fixed-Time synchronIZATION finite-time synchronIZATION CONTINUOUS Controller
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