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Novel Model of Proton Exchange Membrane Fuel Cell with Predictive Control Using Hildreth Algorithm Based on Fractional-order Dynamic Model
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作者 Chu Kaihui Qi Zhidong +1 位作者 Qin Hao Shan Liang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期122-135,共14页
Considering the multivariable and fractional-order characteristics of proton exchange membrane fuel cells(PEMFCs),a fractional-order subspace identification method(FOSIM)is proposed in this paper to establish a fracti... Considering the multivariable and fractional-order characteristics of proton exchange membrane fuel cells(PEMFCs),a fractional-order subspace identification method(FOSIM)is proposed in this paper to establish a fractionalorder state space(FOSS)model,which can be expressed as a multivariable configuration with two inputs,hydrogenflow rate and stack current,and two outputs,cell voltage and power.Based on this model,a novel constrained optimal control law named the Hildreth model predictive control(H-MPC)strategy is created,which employs a Hildreth quadratic programming algorithm to adjust the output power of fuel cells through adaptively regulating hydrogen flow and stack current.dSPACE semi-physical simulation results demonstrate that,compared with proportional-integral-derivative and quadratic programming MPC(QP-MPC),the proposed H-MPC exhibits better tracking ability and strong robustness against variations of PEMFC power. 展开更多
关键词 PEMFC fractional-order subspace identification method fractional-order state space H-MPC
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Sliding-mode-based preassigned-time control of a class of memristor chaotic systems
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作者 Jinrong Fan Qiang Lai +1 位作者 Qiming Wang Leimin Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期161-166,共6页
This paper addresses the preassigned-time chaos control problem of memristor chaotic systems with time delays.Since the introduction of memristor,the presented models are nonlinear systems with chaotic dynamics.First,... This paper addresses the preassigned-time chaos control problem of memristor chaotic systems with time delays.Since the introduction of memristor,the presented models are nonlinear systems with chaotic dynamics.First,the TS fuzzy method is adopted to describe the chaotic systems.Then,a sliding-model-based control approach is proposed to achieve the preassigned-time stabilization of the presented models,where the upper bound of stabilization time can be arbitrarily specified in advance.Finally,simulation results demonstrate the validity of presented control approach and theoretic results. 展开更多
关键词 memristor chaotic system TS fuzzy method preassigned-time stabilization sliding-mode control
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True-temperature inversion algorithm for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization
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作者 Mei Liang Zhuo Sun +3 位作者 Jiasong Liu Yongsheng Wang Lei Liang Long Zhang 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第1期55-62,共8页
Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difficult inversion problems with unknown emissivity.Fractional-order... Herein,a method of true-temperature inversion for a multi-wavelength pyrometer based on fractional-order particle-swarm optimization is proposed for difficult inversion problems with unknown emissivity.Fractional-order calculus has the inherent advantage of easily jumping out of local extreme values;here,it is introduced into the particle-swarm algorithm to invert the true temperature.An improved adaptive-adjustment mechanism is applied to automatically adjust the current velocity order of the particles and update their velocity and position values,increasing the accuracy of the true temperature values.The results of simulations using the proposed algorithm were compared with three algorithms using typical emissivity models:the internal penalty function algorithm,the optimization function(fmincon)algorithm,and the conventional particle-swarm optimization algorithm.The results show that the proposed algorithm has good accuracy for true-temperature inversion.Actual experimental results from a rocket-motor plume were used to demonstrate that the true-temperature inversion results of this algorithm are in good agreement with the theoretical true-temperature values. 展开更多
关键词 fractional-order particle swarm True-temperature inversion algorithm Multi-wavelength pyrometer
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Intelligent Fractional-Order Controller for SMES Systems in Renewable Energy-Based Microgrid
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作者 Aadel M.Alatwi Abualkasim Bakeer +3 位作者 Sherif A.Zaid Ibrahem E.Atawi Hani Albalawi Ahmed M.Kassem 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1807-1830,共24页
An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.Howe... An autonomous microgrid that runs on renewable energy sources is presented in this article.It has a supercon-ducting magnetic energy storage(SMES)device,wind energy-producing devices,and an energy storage battery.However,because such microgrids are nonlinear and the energy they create varies with time,controlling and managing the energy inside them is a difficult issue.Fractional-order proportional integral(FOPI)controller is recommended for the current research to enhance a standalone microgrid’s energy management and performance.The suggested dedicated control for the SMES comprises two loops:the outer loop,which uses the FOPI to regulate the DC-link voltage,and the inner loop,responsible for regulating the SMES current,is constructed using the intelligent FOPI(iFOPI).The FOPI+iFOPI parameters are best developed using the dandelion optimizer(DO)approach to achieve the optimum performance.The suggested FOPI+iFOPI controller’s performance is contrasted with a conventional PI controller for variations in wind speed and microgrid load.The optimal FOPI+iFOPI controller manages the voltage and frequency of the load.The behavior of the microgrid as a reaction to step changes in load and wind speed was measured using the proposed controller.MATLAB simulations were used to evaluate the recommended system’s performance.The results of the simulations showed that throughout all interruptions,the recommended microgrid provided the load with AC power with a constant amplitude and frequency.In addition,the required load demand was accurately reduced.Furthermore,the microgrid functioned incredibly well despite SMES and varying wind speeds.Results obtained under identical conditions were compared with and without the best FOPI+iFOPI controller.When utilizing the optimal FOPI+iFOPI controller with SMES,it was found that the microgrid performed better than the microgrid without SMES. 展开更多
关键词 fractional-order proportional integral(FOPI) intelligent controller renewable energy resources superconducting magnetic energy storage OPTIMIZATION
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Numerical Simulation and Parameter Estimation of Fractional-Order Dynamic Epidemic Model for COVID-19
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作者 Rong Kang Tianzeng Li 《Journal of Applied Mathematics and Physics》 2024年第10期3469-3495,共27页
The outbreak of COVID-19 in 2019 resulted in numerous infections and deaths. In order to better study the transmission of COVID-19, this article adopts an improved fractional-order SIR model. Firstly, the properties o... The outbreak of COVID-19 in 2019 resulted in numerous infections and deaths. In order to better study the transmission of COVID-19, this article adopts an improved fractional-order SIR model. Firstly, the properties of the model are studied, including the feasible domain and bounded solutions of the system. Secondly, the stability of the system is discussed, among other things. Then, the GMMP method is introduced to obtain numerical solutions for the COVID-19 system and combined with the improved MH-NMSS-PSO parameter estimation method to fit the real data of Delhi, India from April 1, 2020 to June 30, 2020. The results show that the fitting effect is quite ideal. Finally, long-term predictions were made on the number of infections. We accurately estimate that the peak number of infections in Delhi, India, can reach around 2.1 million. This paper also compares the fitting performance of the integer-order COVID-19 model and the fractional-order COVID-19 model using the real data from Delhi. The results indicate that the fractional-order model with different orders, as we proposed, performs the best. 展开更多
关键词 Parameter Estimation COVID-19 Infectious Disease Model fractional-order Derivative
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Fractional-Order Super-Twisting Sliding-Mode Procedure Design for a Class of Fractional-Order Nonlinear Dynamic Underwater Robots 被引量:1
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作者 Farideh Shahbazi Mahmood Mahmoodi Reza Ghasemi 《Journal of Marine Science and Application》 CSCD 2020年第1期64-71,共8页
The purpose of this study is to design a fractional-order super-twisting sliding-mode controller for a class of nonlinear fractionalorder systems.The proposed method has the following advantages:(1)Lyapunov stability ... The purpose of this study is to design a fractional-order super-twisting sliding-mode controller for a class of nonlinear fractionalorder systems.The proposed method has the following advantages:(1)Lyapunov stability of the overall closed-loop system,(2)output tracking error’s convergence to zero,(3)robustness against external uncertainties and disturbances,and(4)reduction of the chattering phenomenon.To investigate the performance of the method,the proposed controller is applied to an autonomous underwater robot and Lorenz chaotic system.Finally,a simulation is performed to verify the potential of the proposed method. 展开更多
关键词 Underwater robot fractional-order system sliding-mode control Super-twisting algorithm Lyapunov function
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Practical bipartite consensus for multi-agent systems:A barrier function-based adaptive sliding-mode control approach 被引量:3
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作者 Boda Ning Qing-Long Han Xiaohua Ge 《Journal of Automation and Intelligence》 2023年第1期14-19,共6页
This paper is concerned with bipartite consensus tracking for multi-agent systems with unknown disturbances.A barrier function-based adaptive sliding-mode control(SMC)approach is proposed such that the bipartite stead... This paper is concerned with bipartite consensus tracking for multi-agent systems with unknown disturbances.A barrier function-based adaptive sliding-mode control(SMC)approach is proposed such that the bipartite steady-state error is converged to a predefined region of zero in finite time.Specifically,based on an error auxiliary taking neighboring antagonistic interactions into account,an SMC law is designed with an adaptive gain.The gain can switch to a positive semi-definite barrier function to ensure that the error auxiliary is constrained to a predefined neighborhood of zero,which in turn guarantees practical bipartite consensus tracking.A distinguished feature of the proposed controller is its independence on the bound of disturbances,while the input chattering phenomenon is alleviated.Finally,a numerical example is provided to verify the effectiveness of the proposed controller. 展开更多
关键词 Barrier functions Practical bipartite consensus Multi-agent systems Signed graphs sliding-mode control
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Reliability analysis of torpedo loading based on fractional-order optimization model
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作者 YANG Cheng LIANG Qingwei +1 位作者 HAO Xinyu LIN Sheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第3期798-803,共6页
A fractional-order cumulative optimization GM(1,2)model based on grey theory is proposed to study the relationship between torpedo loading and working reliabilities.In this model,the average relative error function re... A fractional-order cumulative optimization GM(1,2)model based on grey theory is proposed to study the relationship between torpedo loading and working reliabilities.In this model,the average relative error function related to order and background value is established.Taking the average relative error function as the objective function,the optimal value of the two parameters is obtained through the optimization method,and the minimum value of the average relative error is determined.The calculation example shows that this method can greatly improve the accuracy of the model and more accurately reflect the relationship between torpedo loading and working reliabilities compared with the traditional GM(1,2)model. 展开更多
关键词 TORPEDO loading reliability working reliability grey theory fractional-order
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Firing activities in a fractional-order Hindmarsh–Rose neuron with multistable memristor as autapse
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作者 李志军 谢文强 +1 位作者 曾金芳 曾以成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期227-238,共12页
Considering the fact that memristors have the characteristics similar to biological synapses, a fractional-order multistable memristor is proposed in this paper. It is verified that the fractional-order memristor has ... Considering the fact that memristors have the characteristics similar to biological synapses, a fractional-order multistable memristor is proposed in this paper. It is verified that the fractional-order memristor has multiple local active regions and multiple stable hysteresis loops, and the influence of fractional-order on its nonvolatility is also revealed. Then by considering the fractional-order memristor as an autapse of Hindmarsh–Rose(HR) neuron model, a fractional-order memristive neuron model is developed. The effects of the initial value, external excitation current, coupling strength and fractional-order on the firing behavior are discussed by time series, phase diagram, Lyapunov exponent and inter spike interval(ISI) bifurcation diagram. Three coexisting firing patterns, including irregular asymptotically periodic(A-periodic)bursting, A-periodic bursting and chaotic bursting, dependent on the memristor initial values, are observed. It is also revealed that the fractional-order can not only induce the transition of firing patterns, but also change the firing frequency of the neuron. Finally, a neuron circuit with variable fractional-order is designed to verify the numerical simulations. 展开更多
关键词 fractional-order multistable NEURON FIRING locally-active memristor
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BIFURCATION CONTROL FOR A FRACTIONAL-ORDER DELAYED SEIR RUMOR SPREADING MODEL WITH INCOMMENSURATE ORDERS
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作者 叶茂林 蒋海军 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2662-2682,共21页
A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation i... A fractional-order delayed SEIR rumor spreading model with a nonlinear incidence function is established in this paper,and a novel strategy to control the bifurcation of this model is proposed.First,Hopf bifurcation is investigated by considering time delay as bifurcation parameter for the system without a feedback controller.Then,a state feedback controller is designed to control the occurrence of bifurcation in advance or to delay it by changing the parameters of the controller.Finally,in order to verify the theoretical results,some numerical simulations are given. 展开更多
关键词 rumor spreading fractional-order time delay bifurcation control
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Robust Stability Analysis of Smith Predictor Based Interval Fractional-Order Control Systems:A Case Study in Level Control Process
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作者 Majid Ghorbani Mahsan Tavakoli-Kakhki +1 位作者 Aleksei Tepljakov Eduard Petlenkov 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期762-780,共19页
The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertaint... The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertainties are a type of parametric uncertainties that cannot be avoided when modeling real-world plants.Also,in the considered Smith predictor control structure it is supposed that the controller is a fractional-order proportional integral derivative(FOPID)controller.To the best of the authors'knowledge,no method has been developed until now to analyze the robust stability of a Smith predictor based fractional-order control system in the presence of the simultaneous uncertainties in gain,time-constants,and time delay.The three primary contributions of this study are as follows:ⅰ)a set of necessary and sufficient conditions is constructed using a graphical method to examine the robust stability of a Smith predictor-based fractionalorder control system—the proposed method explicitly determines whether or not the FOPID controller can robustly stabilize the Smith predictor-based fractional-order control system;ⅱ)an auxiliary function as a robust stability testing function is presented to reduce the computational complexity of the robust stability analysis;andⅲ)two auxiliary functions are proposed to achieve the control requirements on the disturbance rejection and the noise reduction.Finally,four numerical examples and an experimental verification are presented in this study to demonstrate the efficacy and significance of the suggested technique. 展开更多
关键词 Interval uncertainty FOPID controller fractional-order systems robust stability analysis smith predictor
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Quasi-synchronization of fractional-order complex networks with random coupling via quantized control
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作者 张红伟 程然 丁大为 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期355-363,共9页
We investigate the quasi-synchronization of fractional-order complex networks(FCNs) with random coupling via quantized control. Firstly, based on the logarithmic quantizer theory and the Lyapunov stability theory, a n... We investigate the quasi-synchronization of fractional-order complex networks(FCNs) with random coupling via quantized control. Firstly, based on the logarithmic quantizer theory and the Lyapunov stability theory, a new quantized feedback controller, which can make all nodes of complex networks quasi-synchronization and eliminate the disturbance of random coupling in the system state, is designed under non-delay conditions. Secondly, we extend the theoretical results under non-delay conditions to time-varying delay conditions and design another form of quantization feedback controller to ensure that the network achieves quasi-synchronization. Furthermore, the error bound of quasi-synchronization is obtained.Finally, we verify the accuracy of our results using two numerical simulation examples. 展开更多
关键词 complex network fractional-order random coupling time-varying delay QUASI-SYNCHRONIZATION quantized control
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Free vibration of thermo-elastic microplate based on spatiotemporal fractional-order derivatives with nonlocal characteristic length and time
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作者 Lingkang ZHAO Peijun WEI Yueqiu LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第1期109-124,共16页
A fractional-order thermo-elastic model taking into account the small-scale effects of the thermo-elastic coupled behavior is developed to study the free vibration of a higher-order shear microplate.The nonlocal strai... A fractional-order thermo-elastic model taking into account the small-scale effects of the thermo-elastic coupled behavior is developed to study the free vibration of a higher-order shear microplate.The nonlocal strain gradient theory is modified with the introduction of the fractional-order derivatives and the nonlocal characteristic length.The Fourier heat conduction is replaced by the non-Fourier heat conduction with the introduction of the fractional order and the memory characteristic time.Numerical calculations are performed to analyze the effects of the nonlocal strain gradient parameters,the spatiotemporal fractional order,the nonlocal characteristic length,and the memory characteristic time on the natural frequencies,the vibration attenuation,and the phase shift between the temperature field and the displacement field.The numerical results show that the new thermo-elastic model with the spatiotemporal fractional order can provide more exquisite descriptions of the thermo-elastic behavior at a small scale. 展开更多
关键词 orthotropic higher-order plate nonlocal strain gradient thermo-elastic coupling fractional-order derivative free vibration
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Numerical Simulation of the Fractional-Order Lorenz Chaotic Systems with Caputo Fractional Derivative
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作者 Dandan Dai Xiaoyu Li +2 位作者 Zhiyuan Li Wei Zhang Yulan Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1371-1392,共22页
Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to pursue.Based on this problem,this ... Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to pursue.Based on this problem,this paper introduces a high-precision numerical approach.Some complex dynamic behavior of fractional-order Lorenz chaotic systems are shown by using the present method.We observe some novel dynamic behavior in numerical experiments which are unlike any that have been previously discovered in numerical experiments or theoretical studies.We investigate the influence of α_(1),α_(2),α_(3) on the numerical solution of fractional-order Lorenz chaotic systems.The simulation results of integer order are in good agreement with those of othermethods.The simulation results of numerical experiments demonstrate the effectiveness of the present method. 展开更多
关键词 Novel complex dynamic behavior numerical simulation fractional-order lorenz chaotic systems HIGH-PRECISION
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High-speed train cooperativecontrol based on fractional-ordersliding mode adaptive algorithm
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作者 Junting Lin Mingjun Ni Huadian Liang 《Railway Sciences》 2023年第1期84-100,共17页
Purpose–This study aims to propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under disturbance environment in moving block... Purpose–This study aims to propose an adaptive fractional-order sliding mode controller to solve the problem of train speed tracking control and position interval control under disturbance environment in moving block system,so as to improve the tracking efficiency and collision avoidance performance.Design/methodology/approach–The mathematical model of information interaction between trains is established based on algebraic graph theory,so that the train can obtain the state information of adjacent trains,and then realize the distributed cooperative control of each train.In the controller design,the sliding mode control and fractional calculus are combined to avoid the discontinuous switching phenomenon,so as to suppress the chattering of sliding mode control,and a parameter adaptive law is constructed to approximate the time-varying operating resistance coefficient.Findings–The simulation results show that compared with proportional integral derivative(PID)control and ordinary sliding mode control,the control accuracy of the proposed algorithm in terms of speed is,respectively,improved by 25%and 75%.The error frequency and fluctuation range of the proposed algorithm are reduced in the position error control,the error value tends to 0,and the operation trend tends to be consistent.Therefore,the control method can improve the control accuracy of the system and prove that it has strong immunity.Originality/value–The algorithm can reduce the influence of external interference in the actual operating environment,realize efficient and stable tracking of trains,and ensure the safety of train control. 展开更多
关键词 High-speed trains Sliding mode control fractional-order differentiation Adaptive law Cooperative control
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Circuit implementation of a new hyperchaos in fractional-order system 被引量:12
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作者 刘崇新 刘凌 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2829-2836,共8页
This paper introduces a new four-dimensional (4D) hyperchaotic system, which has only two quadratic nonlinearity parameters but with a complex topological structure. Some complicated dynamical properties are then in... This paper introduces a new four-dimensional (4D) hyperchaotic system, which has only two quadratic nonlinearity parameters but with a complex topological structure. Some complicated dynamical properties are then investigated in detail by using bifurcations, Poincare mapping, LE spectra. Furthermore, a simple fourth-order electronic circuit is designed for hardware implementation of the 4D hyperchaotic attractors. In particular, a remarkable fractional-order circuit diagram is designed for physically verifying the hyperchaotic attractors existing not only in the integer-order system but also in the fractional-order system with an order as low as 3.6. 展开更多
关键词 hyperchaotic system fractional-order system integer-order chaotic circuit fractional-order circuit
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Chaotic dynamics of the fractional-order Ikeda delay system and its synchronization 被引量:43
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作者 卢俊国 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第2期301-305,共5页
In this paper we numerically investigate the chaotic behaviours of the fractional-order Ikeda delay system. The results show that chaos exists in the fractional-order Ikeda delay system with order less than 1. The low... In this paper we numerically investigate the chaotic behaviours of the fractional-order Ikeda delay system. The results show that chaos exists in the fractional-order Ikeda delay system with order less than 1. The lowest order for chaos to be a, ble to appear in this system is found to be 0.1. Master-slave synchronization of chaotic fractional-order Ikeda delay systems with linear coupling is also studied. 展开更多
关键词 CHAOS Ikeda delay system fractional-order system fractional calculus
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Chaotic synchronization for a class of fractional-order chaotic systems 被引量:15
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作者 周平 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1263-1266,共4页
In this paper, a very simple synchronization method is presented for a class of fractional-order chaotic systems only via feedback control. The synchronization technique, based on the stability theory of fractional-or... In this paper, a very simple synchronization method is presented for a class of fractional-order chaotic systems only via feedback control. The synchronization technique, based on the stability theory of fractional-order systems, is simple and theoretically rigorous. 展开更多
关键词 SYNCHRONIZATION fractional-order chaotic systems stability theory
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SLIDING-MODE CONTROL OF UNOERTAINTY BILINEAR SYSTEM
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作者 王海涛 王先来 李光泉 《Transactions of Tianjin University》 EI CAS 1999年第1期57-60,共4页
In this paper,the sliding-mode control of a bilinear system is studied. It improves the dynamicresponse of the closedweloop system around the original point and is rather robust to the bounded disturbance. At last,the... In this paper,the sliding-mode control of a bilinear system is studied. It improves the dynamicresponse of the closedweloop system around the original point and is rather robust to the bounded disturbance. At last,the model of an ammonia synthesis reactor is adopted to illustrate the phenomenon described. 展开更多
关键词 bilinear system sliding-mode control ROBUSTNESS
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Realization of fractional-order Liu chaotic system by circuit 被引量:6
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作者 逯俊杰 刘崇新 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第6期1586-1590,共5页
In this paper, chaotic behaviours in the fractional-order Liu system are studied. Based on the approximation theory of fractional-order operator, circuits are designed to simulate the fractional- order Liu system with... In this paper, chaotic behaviours in the fractional-order Liu system are studied. Based on the approximation theory of fractional-order operator, circuits are designed to simulate the fractional- order Liu system with q=0.1 - 0.9 in a step of 0.1, and an experiment has demonstrated the 2.7-order Liu system. The simulation results prove that the chaos exists indeed in the fractional-order Liu system with an order as low as 0.3. The experimental results prove that the fractional-order chaotic system can be realized by using hardware devices, which lays the foundation for its practical applications. 展开更多
关键词 fractional-order Liu system circuit simulation circuit experiment
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