The Experts below are selected from a list of 1914405 Experts worldwide ranked by ideXlab platform
Shaocheng Tong - One of the best experts on this subject based on the ideXlab platform.
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observer based adaptive fuzzy decentralized optimal control design for strict feedback nonlinear large scale Systems
IEEE Transactions on Fuzzy Systems, 2018Co-Authors: Shaocheng Tong, Kangkang Sun, Shuai SuiAbstract:In this paper, the problem of adaptive fuzzy decentralized optimal control is investigated for a class of nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear Large-Scale Systems contain the unknown nonlinear functions and unmeasured states. By utilizing the fuzzy logic Systems to approximate the unknown nonlinear functions and cost functions, a fuzzy state observer is established to estimate the unmeasured states. The control design is divided into two phases. First, by using the state observer and the backstepping design technique, a feedforward decentralized controller with parameters adaptive laws is designed, by which the original controlled strict-feedback nonlinear Large-Scale system is transformed into an equivalent affine nonlinear Large-Scale system. Second, by using adaptive dynamic programming theory, a feedback decentralized optimal controller is developed for the equivalent affine nonlinear system. The whole adaptive fuzzy decentralized optimal control scheme consists of a feedforward decentralized controller and a feedback decentralized optimal controller. It is shown that the proposed adaptive fuzzy decentralized optimal control approach can guarantee that all the signals in the closed-loop system are bounded, and the tracking errors converge to a small neighborhood of zero. In addition, the proposed control approach can guarantee that the cost functions are minimized. Simulation results are given to demonstrate the effectiveness of the proposed control approach.
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finite time filter decentralized control for nonstrict feedback nonlinear large scale Systems
IEEE Transactions on Fuzzy Systems, 2018Co-Authors: Shuai Sui, Shaocheng Tong, C Philip L ChenAbstract:This paper solves the finite-time decentralized control problem for uncertain nonlinear Large-Scale Systems in nonstrict-feedback form. The considered controlled plants are different from the previous results of finite-time control Systems, which are the nonstrict-feedback Large-Scale Systems with the unknown functions consisting of all states, interactions, and immeasurable states. Fuzzy logic Systems and a filter-based state observer are utilized to model uncertain Systems and deal with the immeasurable states, respectively. By combining the backstepping recursive design with Lyapunov function theory, a finite-time adaptive fuzzy decentralized control approach is raised. It is testified that the developed control strategy can guarantee that the closed-loop signals are bounded, and the outputs of Systems have satisfactory tracking performance in a finite time. A quadruple-tank process system is given to testify the effectiveness and applicability of the proposed approach.
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observed based adaptive fuzzy decentralized tracking control for switched uncertain nonlinear large scale Systems with dead zones
Systems Man and Cybernetics, 2016Co-Authors: Shaocheng Tong, Lili Zhang, Yongming LiAbstract:In this paper, the problem of adaptive fuzzy decentralized output-feedback control design is investigated for a class of switched nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear Large-Scale Systems contain the unknown nonlinearities and dead zones, the switching signals with average dwell time, and without the direct requirement of the states being available for feedback. Fuzzy logic Systems are utilized to approximate the unknown nonlinear functions, a fuzzy switched decentralized state observer is designed and thus via it the immeasurable states are obtained. By applying the adaptive decentralized backstepping design technique, an adaptive fuzzy decentralized output-feedback tracking control approach is developed for the switched subSystems. The stability of the whole closed-loop system is proved by using the Lyapunov function and the average dwell-time methods. Satisfactory tracking performance is achieved under the switching signals with average dwell time. The simulation example is provided to indicate the effectiveness of the proposed control method.
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prescribed performance adaptive fuzzy output feedback dynamic surface control for nonlinear large scale Systems with time delays
Information Sciences, 2015Co-Authors: Shaocheng TongAbstract:The adaptive fuzzy decentralized output-feedback control method is proposed for a class of nonlinear Large-Scale Systems. The considered nonlinear Systems contain unstructured uncertainties, unknown time-varying delays, and immeasurable states. Fuzzy logic Systems are used to approximate the unstructured uncertainties, and a fuzzy state observer is designed to estimate the unmeasured states. Based on the backstepping recursive design technique and the prescribed performance technique, a new adaptive fuzzy output-feedback control method is developed. In order to overcome the problem of "explosion of complexity" inherent in the backstepping control design, the dynamic surface control (DSC) technique is introduced into the control scheme. Based on Lyapunov-Krasovskii functional, it is proved that all the signals in the closed-loop system are bounded and the tracking errors remain an adjustable neighborhood of the origin with the prescribed performance bounds. The simulation examples and comparison with the previous control methods are provided to show the effectiveness of the proposed control approach.
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observer based adaptive decentralized fuzzy fault tolerant control of nonlinear large scale Systems with actuator failures
IEEE Transactions on Fuzzy Systems, 2014Co-Authors: Shaocheng Tong, Yongming LiAbstract:This paper investigates the adaptive fuzzy decentralized fault-tolerant control (FTC) problem for a class of nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear system contains the unknown nonlinear functions, i.e., unmeasured states and actuator faults, which are modeled as both loss of effectiveness and lock-in-place. With the help of fuzzy logic Systems to approximate the unknown nonlinear functions, a fuzzy adaptive observer is designed to estimate the unmeasured states. By combining the backstepping technique with the nonlinear FTC theory, a novel adaptive fuzzy decentralized FTC scheme is developed. It is proved that the proposed control approach can guarantee that all the signals of the resulting closed-loop system are bounded, and the tracking errors between the system outputs and the reference signals converge to a small neighborhood of zero by appropriate choice of the design parameters. Simulation results are provided to show the effectiveness of the control approach.
Yongming Li - One of the best experts on this subject based on the ideXlab platform.
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observed based adaptive fuzzy decentralized tracking control for switched uncertain nonlinear large scale Systems with dead zones
Systems Man and Cybernetics, 2016Co-Authors: Shaocheng Tong, Lili Zhang, Yongming LiAbstract:In this paper, the problem of adaptive fuzzy decentralized output-feedback control design is investigated for a class of switched nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear Large-Scale Systems contain the unknown nonlinearities and dead zones, the switching signals with average dwell time, and without the direct requirement of the states being available for feedback. Fuzzy logic Systems are utilized to approximate the unknown nonlinear functions, a fuzzy switched decentralized state observer is designed and thus via it the immeasurable states are obtained. By applying the adaptive decentralized backstepping design technique, an adaptive fuzzy decentralized output-feedback tracking control approach is developed for the switched subSystems. The stability of the whole closed-loop system is proved by using the Lyapunov function and the average dwell-time methods. Satisfactory tracking performance is achieved under the switching signals with average dwell time. The simulation example is provided to indicate the effectiveness of the proposed control method.
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observer based adaptive decentralized fuzzy fault tolerant control of nonlinear large scale Systems with actuator failures
IEEE Transactions on Fuzzy Systems, 2014Co-Authors: Shaocheng Tong, Yongming LiAbstract:This paper investigates the adaptive fuzzy decentralized fault-tolerant control (FTC) problem for a class of nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear system contains the unknown nonlinear functions, i.e., unmeasured states and actuator faults, which are modeled as both loss of effectiveness and lock-in-place. With the help of fuzzy logic Systems to approximate the unknown nonlinear functions, a fuzzy adaptive observer is designed to estimate the unmeasured states. By combining the backstepping technique with the nonlinear FTC theory, a novel adaptive fuzzy decentralized FTC scheme is developed. It is proved that the proposed control approach can guarantee that all the signals of the resulting closed-loop system are bounded, and the tracking errors between the system outputs and the reference signals converge to a small neighborhood of zero by appropriate choice of the design parameters. Simulation results are provided to show the effectiveness of the control approach.
Shuai Sui - One of the best experts on this subject based on the ideXlab platform.
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observer based adaptive fuzzy decentralized optimal control design for strict feedback nonlinear large scale Systems
IEEE Transactions on Fuzzy Systems, 2018Co-Authors: Shaocheng Tong, Kangkang Sun, Shuai SuiAbstract:In this paper, the problem of adaptive fuzzy decentralized optimal control is investigated for a class of nonlinear Large-Scale Systems in strict-feedback form. The considered nonlinear Large-Scale Systems contain the unknown nonlinear functions and unmeasured states. By utilizing the fuzzy logic Systems to approximate the unknown nonlinear functions and cost functions, a fuzzy state observer is established to estimate the unmeasured states. The control design is divided into two phases. First, by using the state observer and the backstepping design technique, a feedforward decentralized controller with parameters adaptive laws is designed, by which the original controlled strict-feedback nonlinear Large-Scale system is transformed into an equivalent affine nonlinear Large-Scale system. Second, by using adaptive dynamic programming theory, a feedback decentralized optimal controller is developed for the equivalent affine nonlinear system. The whole adaptive fuzzy decentralized optimal control scheme consists of a feedforward decentralized controller and a feedback decentralized optimal controller. It is shown that the proposed adaptive fuzzy decentralized optimal control approach can guarantee that all the signals in the closed-loop system are bounded, and the tracking errors converge to a small neighborhood of zero. In addition, the proposed control approach can guarantee that the cost functions are minimized. Simulation results are given to demonstrate the effectiveness of the proposed control approach.
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finite time filter decentralized control for nonstrict feedback nonlinear large scale Systems
IEEE Transactions on Fuzzy Systems, 2018Co-Authors: Shuai Sui, Shaocheng Tong, C Philip L ChenAbstract:This paper solves the finite-time decentralized control problem for uncertain nonlinear Large-Scale Systems in nonstrict-feedback form. The considered controlled plants are different from the previous results of finite-time control Systems, which are the nonstrict-feedback Large-Scale Systems with the unknown functions consisting of all states, interactions, and immeasurable states. Fuzzy logic Systems and a filter-based state observer are utilized to model uncertain Systems and deal with the immeasurable states, respectively. By combining the backstepping recursive design with Lyapunov function theory, a finite-time adaptive fuzzy decentralized control approach is raised. It is testified that the developed control strategy can guarantee that the closed-loop signals are bounded, and the outputs of Systems have satisfactory tracking performance in a finite time. A quadruple-tank process system is given to testify the effectiveness and applicability of the proposed approach.
Jianbin Qiu - One of the best experts on this subject based on the ideXlab platform.
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decentralized fixed order piecewise affine dynamic output feedback controller design for discrete time nonlinear large scale Systems
IEEE Access, 2017Co-Authors: Anqing Wang, Jianbin QiuAbstract:This paper proposes a novel decentralized robust $\mathscr H_{\infty }$ fixed-order dynamic output feedback (DOF) controller design approach for discrete-time nonlinear Large-Scale Systems via Takagi-Sugeno fuzzy-affine models. By a state-input augmentation method and piecewise quadratic Lyapunov functions, some sufficient conditions for decentralized fixed-order piecewise affine DOF controller synthesis are given. It is shown that by some convexification techniques, the controller gains can be obtained by solving a set of linear matrix inequalities. Two simulation examples are carried out to verify the effectiveness of the proposed design method.
Paulo Verissimo - One of the best experts on this subject based on the ideXlab platform.
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cesiumspray a precise and accurate global time servicefor large scale Systems
Real-time Systems, 1997Co-Authors: Paulo Verissimo, Luis Rodrigues, Antonio CasimiroAbstract:In Large-Scale Systems, such as Internet-based distributed Systems, classical clock-synchronization solutions become impractical or poorly performing, due to the number of nodes and/or the distance among them. We present a global time service for world-wide Systems, based on an innovative clock synchronization scheme, named CesiumSpray. The service exhibits high precision and accuracy; it is virtually indefinitely scalable; and it is fault-tolerant. It is deterministic for real-time machinery in the local area, which makes it particularly well-suited for, though not limited to, Large-Scale real-time Systems. The main features of our clock synchronization scheme can be summarized as follows: hybrid external/internal synchronization protocol improves effectiveness of synchronization; heterogeneous failure semantics for clocks and processors improves previous lower bounds on processors; two-level hierarchy improves scalability. The root of the hierarchy is the GPS satellite constellation, which ’’sprays‘‘ its reference time over a set of nodes provided with GPS receivers, one per local network. The second level of the hierarchy performs internal synchronization, further ’’spraying‘‘ the external time inside the local network.
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totally ordered multicast in large scale Systems
International Conference on Distributed Computing Systems, 1996Co-Authors: Luis Rodrigues, Henrique Fonseca, Paulo VerissimoAbstract:Totally ordered multicast protocols have proved to be extremely useful in supporting fault-tolerant distributed applications. This paper compares the performance of the two main classes of protocols providing total order in Large-Scale Systems (token-site and symmetric protocols) and proposes a new dynamic hybrid protocol that, when applied to Systems where the topology/traffic patterns are not known a priori, offers a much lower latency than any of the previous classes of protocols in isolation.
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totally ordered multicast in large scale Systems
Large scale systems, 1995Co-Authors: Luis Rodrigues, Henrique Fonseca, Paulo VerissimoAbstract:Totally ordered multicast protocols have proved to be extremely useful in supporting fault-tolerant distributed applications. This paper compares the performance of the two main classes of protocols providing total order in Large-Scale Systems: token-site and symmetric protocols. The paper shows that both classes of protocols can exhibit a latency close to 2D, where D is the message transit delay between two processes. In the face of these observations, the paper makes the following contributions: it presents a rate-synchronization scheme for symmetric protocols that exhibits a latency close to D+t, where t is the inter-message transmission time; it proposes a new hybrid protocol and shows that the hybrid scheme for heterogeneous topologies performs better than any of the previous classes of protocols in isolation; finally, the paper presents an algorithm that allows a process to dynamically adapt to changes in throughput and in network delays. The combination of these three techniques results in a dynamic hybrid scheme that, when applied to Systems where the topology/traffic patterns are not known a priori, offers a much lower latency than non-hybrid approaches.
