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Nonlocal symmetry, optimal systems, and explicit solutions of the mKdV equation 被引量:2
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作者 辛祥鹏 苗倩 陈勇 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第1期49-54,共6页
The nonlocal symmetry of the mKdV equation is obtained from the known Lax pair; it is successfully localized to Lie point symmetries in the enlarged space by introducing suitable auxiliary dependent variables. For the... The nonlocal symmetry of the mKdV equation is obtained from the known Lax pair; it is successfully localized to Lie point symmetries in the enlarged space by introducing suitable auxiliary dependent variables. For the closed prolongation of the nonlocal symmetry, the details of the construction for a one-dimensional optimal system are presented. Furthermore, using the associated vector fields of the obtained symmetry, we give the reductions by the one-dimensional sub-algebras and the explicit analytic interaction solutions between cnoidal waves and kink solitary waves, which provide a way to study the interactions among these types of ocean waves. For some of the interesting solutions, the figures are given to show their properties. 展开更多
关键词 nonlocal symmetry optimal system prolonged system explicit solutions
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One-Dimensional Optimal System and Similarity Reductions of Wu–Zhang Equation 被引量:1
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作者 熊娜 李玉奇 +1 位作者 陈俊超 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第7期1-11,共11页
The one-dimensional optimal system for the Lie symmetry group of the(2+1)-dimensional Wu–Zhan equation is constructed by the general and systematic approach. Based on the optimal system, the complete and inequivalent... The one-dimensional optimal system for the Lie symmetry group of the(2+1)-dimensional Wu–Zhan equation is constructed by the general and systematic approach. Based on the optimal system, the complete and inequivalent symmetry reduction systems are presented in the form of table. It is noteworthy that a new Painlev integrable equation with constant coefficient is in the table besides the classic Boussinesq equation and the steady cas of the Wu–Zhang equation. 展开更多
关键词 Wu–Zhang equation optimal system similarity reduction Painlev integrability
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Lie Symmetries,1-Dimensional Optimal System and Optimal Reductions of(1+2)-Dimensional Nonlinear Schrodinger Equation 被引量:1
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作者 Meirong Mu Chaolu Temuer 《Journal of Applied Mathematics and Physics》 2014年第7期603-620,共18页
For a class of (1 + 2)-dimensional nonlinear Schrodinger equations, classical symmetry algebra is found and 1-dimensional optimal system, up to conjugacy, is constructed. Its symmetry reductions are performed for each... For a class of (1 + 2)-dimensional nonlinear Schrodinger equations, classical symmetry algebra is found and 1-dimensional optimal system, up to conjugacy, is constructed. Its symmetry reductions are performed for each class, and someexamples of exact invainvariant solutions are given. 展开更多
关键词 Nonlinear Schrodinger Equation Classical Symmetry optimal system Symmetry Reductions Invariant Solutions
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ONEOptimal:A Maple Package for Generating One-Dimensional Optimal System of Finite Dimensional Lie Algebra
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作者 苗倩 胡晓瑞 陈勇 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第2期160-170,共11页
We present a Maple computer algebra package, ONEOptimal, which can calculate one-dimensional optimal system of finite dimensional Lie algebra for nonlinear equations automatically based on Olver's theory. The core... We present a Maple computer algebra package, ONEOptimal, which can calculate one-dimensional optimal system of finite dimensional Lie algebra for nonlinear equations automatically based on Olver's theory. The core of this theory is viewing the Killing form of the Lie algebra as an invariant for the adjoint representation. Some examples are given to demonstrate the validity and efficiency of the program. 展开更多
关键词 group-invariant solutions optimal system group classification Lie algebra symbolic computation
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Lie symmetry analysis, optimal system and conservation laws of a new(2+1)-dimensional KdV system
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作者 Mengmeng Wang Shoufeng Shen Lizhen Wang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第8期41-49,共9页
In this paper, Lie point symmetries of a new(2+1)-dimensional KdV system are constructed by using the symbolic computation software Maple. Then, the one-dimensional optimal system,associated with corresponding Lie alg... In this paper, Lie point symmetries of a new(2+1)-dimensional KdV system are constructed by using the symbolic computation software Maple. Then, the one-dimensional optimal system,associated with corresponding Lie algebra, is obtained. Moreover, the reduction equations and some explicit solutions based on the optimal system are presented. Finally, the nonlinear selfadjointness is provided and conservation laws of this KdV system are constructed. 展开更多
关键词 Lie point symmetry optimal system symmetry reduction exact solution conservation law
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A Direct Algorithm Maple Package of One-Dimensional Optimal System for Group Invariant Solutions
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作者 Lin Zhang Zhong Han Yong Chen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第1期14-22,共9页
To construct the one-dimensional optimal system of finite dimensional Lie algebra automatically,we develop a new Maple package One Optimal System.Meanwhile,we propose a new method to calculate the adjoint transformati... To construct the one-dimensional optimal system of finite dimensional Lie algebra automatically,we develop a new Maple package One Optimal System.Meanwhile,we propose a new method to calculate the adjoint transformation matrix and find all the invariants of Lie algebra in spite of Killing form checking possible constraints of each classification.Besides,a new conception called invariance set is raised.Moreover,this Maple package is proved to be more efficiency and precise than before by applying it to some classic examples. 展开更多
关键词 symbolic computation mathematics mechanization direct algorithm optimal system
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Lie Symmetries,One-Dimensional Optimal System and Optimal Reduction of(2+1)-Coupled nonlinear Schrodinger Equations
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作者 A.Li Chaolu Temuer 《Journal of Applied Mathematics and Physics》 2014年第7期677-690,共14页
For a class of (1 + 2)-dimensional nonlinear Schrodinger equations, the infinite dimensional Lie algebra of the classical symmetry group is found and the one-dimensional optimal system of an 8-dimensional subalgebra o... For a class of (1 + 2)-dimensional nonlinear Schrodinger equations, the infinite dimensional Lie algebra of the classical symmetry group is found and the one-dimensional optimal system of an 8-dimensional subalgebra of the infinite Lie algebra is constructed. The reduced equations of the equations with respect to the optimal system are derived. Furthermore, the one-dimensional optimal systems of the Lie algebra admitted by the reduced equations are also constructed. Consequently, the classification of the twice optimal symmetry reductions of the equations with respect to the optimal systems is presented. The reductions show that the (1 + 2)-dimensional nonlinear Schrodinger equations can be reduced to a group of ordinary differential equations which is useful for solving the related problems of the equations. 展开更多
关键词 Nonlinear Schrodinger Equations Lie Aymmetry Group Lie algebra optimal system
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Optimal System and Invariant Solutions on ((U<sub>yy</sub>(t,s,y)-U<sub>t</sub>(t,s,y))y-2sU<sub>sy</sub>(t,s,y))y+(s<sup>2</sup>+1)U<sub>ss</sub>(t,s,y)+2sU<sub>s</sub>=0
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作者 Sopita Khamrod 《Applied Mathematics》 2013年第8期1154-1162,共9页
The purpose of this paper is to find the invariant solutions of the reduction of the Navier-Stokes equations where s=z/y ((Uyy(t,s,y)-Ut(t,s,y))y-2sUsy(t,s,y))y+(s2+1)Uss(t,s,y)+2sUs=0 This equation is constructed fro... The purpose of this paper is to find the invariant solutions of the reduction of the Navier-Stokes equations where s=z/y ((Uyy(t,s,y)-Ut(t,s,y))y-2sUsy(t,s,y))y+(s2+1)Uss(t,s,y)+2sUs=0 This equation is constructed from the Navier-Stokes equations rising to a partially invariant solutions of the Navier-Stokes equations. Group classification of the admitted Lie algebras of this equation is obtained. Two-dimensional optimal system is constructed from classification of their subalgebras. All invariant solutions corresponding to these subalgebras are presented. 展开更多
关键词 optimal system INVARIANT SOLUTIONS Partially INVARIANT SOLUTIONS Navier-Stokes Equations
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Optimal System of Subalgebras for the Reduction of the Navier-Stokes Equations
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作者 Sopita Khamrod 《Applied Mathematics》 2013年第1期124-134,共11页
The purpose of this paper is to find the admitted Lie group of the reduction of the Navier-Stokes equationswhere using the basic Lie symmetry method. This equation is constructed from the Navier-Stokes equations risin... The purpose of this paper is to find the admitted Lie group of the reduction of the Navier-Stokes equationswhere using the basic Lie symmetry method. This equation is constructed from the Navier-Stokes equations rising to a partially invariant solutions of the Navier-Stokes equations. Two-dimensional optimal system is determined for symmetry algebras obtained through classification of their subalgebras. Some invariant solutions are also found. 展开更多
关键词 optimal system INVARIANT SOLUTIONS PARTIALLY INVARIANT SOLUTIONS NAVIER-STOKES Equations
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Potential Symmetries, One-Dimensional Optimal System and Invariant Solutions of the Coupled Burgers’ Equations
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作者 Yuexing Bai Sudao Bilige Temuer Chaolu 《Journal of Applied Mathematics and Physics》 2018年第9期1825-1839,共15页
In this paper, we discuss one-dimensional optimal system and the invariant solutions of Coupled Burgers’ equations. By using Wu-differential characteristic set algorithm with the aid of Mathematica software, the clas... In this paper, we discuss one-dimensional optimal system and the invariant solutions of Coupled Burgers’ equations. By using Wu-differential characteristic set algorithm with the aid of Mathematica software, the classical symmetries of the Coupled Burgers’ equations are calculated, and the one-dimensional optimal system of Lie algebra is constructed. And we obtain the invariant solution of the Coupled Burgers’ equations corresponding to one element in one dimensional optimal system by using the invariant method. The results generalize the exact solutions of the Coupled Burgers’ equations. 展开更多
关键词 Potential SYMMETRY ONE-DIMENSIONAL optimal system INVARIANT Solution COUPLED Burgers’ Equations
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Lie Symmetry Analysis, Optimal Systems and Explicit Solutions of the Dispersive Long Wave Equations
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作者 Xiaomei Xue Yushan Bai 《Journal of Applied Mathematics and Physics》 2018年第12期2681-2696,共16页
In this paper, the dispersive long wave equation is studied by Lie symmetry group theory. Firstly, the Lie symmetries of this system are calculated. Secondly, one dimensional optimal systems of Lie algebra and all the... In this paper, the dispersive long wave equation is studied by Lie symmetry group theory. Firstly, the Lie symmetries of this system are calculated. Secondly, one dimensional optimal systems of Lie algebra and all the symmetry reductions are obtained. Finally, based on the power series method and the extended Tanh function method, some new explicit solutions of this system are constructed. 展开更多
关键词 DISPERSIVE Long Wave EQUATIONS LIE SYMMETRY Analysis optimal systems Power Series METHOD Extended Tanh Function METHOD EXPLICIT Solutions
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Actor–Critic Trajectory Controller with Optimal Design for Nonlinear Robotic Systems
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作者 Nien-Tsu Hu Hsiang-Tung Kao +1 位作者 Chin-Sheng Chen Shih-Hao Chang 《Computers, Materials & Continua》 2026年第4期1996-2021,共26页
Trajectory tracking for nonlinear robotic systems remains a fundamental yet challenging problem in control engineering,particularly when both precision and efficiency must be ensured.Conventional control methods are o... Trajectory tracking for nonlinear robotic systems remains a fundamental yet challenging problem in control engineering,particularly when both precision and efficiency must be ensured.Conventional control methods are often effective for stabilization but may not directly optimize long-term performance.To address this limitation,this study develops an integrated framework that combines optimal control principles with reinforcement learning for a single-link robotic manipulator.The proposed scheme adopts an actor–critic structure,where the critic network approximates the value function associated with the Hamilton–Jacobi–Bellman equation,and the actor network generates near-optimal control signals in real time.This dual adaptation enables the controller to refine its policy online without explicit system knowledge.Stability of the closed-loop system is analyzed through Lyapunov theory,ensuring boundedness of the tracking error.Numerical simulations on the single-link manipulator demonstrate that themethod achieves accurate trajectory followingwhile maintaining lowcontrol effort.The results further showthat the actor–critic learning mechanism accelerates convergence of the control policy compared with conventional optimization-based strategies.This work highlights the potential of reinforcement learning integrated with optimal control for robotic manipulators and provides a foundation for future extensions to more complex multi-degree-of-freedom systems.The proposed controller is further validated in a physics-based virtual Gazebo environment,demonstrating stable adaptation and real-time feasibility. 展开更多
关键词 Reinforcement learning optimal control actor–critic algorithm trajectory tracking nonlinear systems robotic manipulator
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A Stochastic Optimal Control for a Class of LTI Systems With a State-Dependent Wiener Process:An Algebraic Approach
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作者 Kento Fujita Daisuke Tsubakino Shiuji Hara 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期489-491,共3页
Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in a... Dear Editor,In this letter,we focus on the algebraic relationship between the coefficient matrices and the solution of the stochastic algebraic Riccati equation.It is revealed that,if the coefficient matrices are in an algebra,then the solution(and also the control gain in many cases)is also in the same algebra.The main result is verified by a numerical simulation. 展开更多
关键词 stochastic optimal control algebraic relationship algebraic approach state dependent Wiener process coefficient matrices stochastic algebraic Riccati equation numerical simulation stochastic algebraic riccati equationit
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Lie Symmetries,Conservation Laws,Optimal System and Similarity Reductions of(2+1)-Dimensional Fractional Hirota-Maccari System
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作者 YU Jicheng FENG Yuqiang 《Journal of Partial Differential Equations》 2025年第2期208-226,共19页
In this paper,Lie symmetry analysis method is applied to one type of mathematical physics equations named the(2+1)-dimensional fractional Hirota-Maccari system.All Lie symmetries and the corresponding conserved vector... In this paper,Lie symmetry analysis method is applied to one type of mathematical physics equations named the(2+1)-dimensional fractional Hirota-Maccari system.All Lie symmetries and the corresponding conserved vectors for the system are obtained.The one-dimensional optimai system is utilized to reduce the aimed equations with Riemann-Liouville fractional derivative to the(1+1)-dimensional fractional partial differential equations with Erdelyi-Kober fractional derivative. 展开更多
关键词 Lie symmetry analysis fractional Hirota-Maccari system one-dimensional optimal system conservation laws
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Bilevel Optimal Scheduling of Island Integrated Energy System Considering Multifactor Pricing 被引量:1
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作者 Xin Zhang Mingming Yao +3 位作者 Daiwen He Jihong Zhang Peihong Yang Xiaoming Zhang 《Energy Engineering》 EI 2025年第1期349-378,共30页
In this paper,a bilevel optimization model of an integrated energy operator(IEO)–load aggregator(LA)is constructed to address the coordinate optimization challenge of multiple stakeholder island integrated energy sys... In this paper,a bilevel optimization model of an integrated energy operator(IEO)–load aggregator(LA)is constructed to address the coordinate optimization challenge of multiple stakeholder island integrated energy system(IIES).The upper level represents the integrated energy operator,and the lower level is the electricity-heatgas load aggregator.Owing to the benefit conflict between the upper and lower levels of the IIES,a dynamic pricing mechanism for coordinating the interests of the upper and lower levels is proposed,combined with factors such as the carbon emissions of the IIES,as well as the lower load interruption power.The price of selling energy can be dynamically adjusted to the lower LA in the mechanism,according to the information on carbon emissions and load interruption power.Mutual benefits and win-win situations are achieved between the upper and lower multistakeholders.Finally,CPLEX is used to iteratively solve the bilevel optimization model.The optimal solution is selected according to the joint optimal discrimination mechanism.Thesimulation results indicate that the sourceload coordinate operation can reduce the upper and lower operation costs.Using the proposed pricingmechanism,the carbon emissions and load interruption power of IEO-LA are reduced by 9.78%and 70.19%,respectively,and the capture power of the carbon capture equipment is improved by 36.24%.The validity of the proposed model and method is verified. 展开更多
关键词 Bilevel optimal scheduling load aggregator integrated energy operator carbon emission dynamic pricing mechanism
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Optimal scheduling method for multi-regional integrated energy system based on dynamic robust optimization algorithm and bi-level Stackelberg model 被引量:1
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作者 Bo Zhou Erchao Li Wenjing Liang 《Global Energy Interconnection》 2025年第3期510-521,共12页
In this study,we construct a bi-level optimization model based on the Stackelberg game and propose a robust optimization algorithm for solving the bi-level model,assuming an actual situation with several participants ... In this study,we construct a bi-level optimization model based on the Stackelberg game and propose a robust optimization algorithm for solving the bi-level model,assuming an actual situation with several participants in energy trading.Firstly,the energy trading process is analyzed between each subject based on the establishment of the operation framework of multi-agent participation in energy trading.Secondly,the optimal operation model of each energy trading agent is established to develop a bi-level game model including each energy participant.Finally,a combination algorithm of improved robust optimization over time(ROOT)and CPLEX is proposed to solve the established game model.The experimental results indicate that under different fitness thresholds,the robust optimization results of the proposed algorithm are increased by 56.91%and 68.54%,respectively.The established bi-level game model effectively balances the benefits of different energy trading entities.The proposed algorithm proposed can increase the income of each participant in the game by an average of 8.59%. 展开更多
关键词 Robust optimization over time Integrated energy system Dynamic problem Stackelberg game
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Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method
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作者 Suliang Ma Zeqing Meng +1 位作者 Mingxuan Chen Yuan Jiang 《Energy Engineering》 EI 2025年第1期63-84,共22页
In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimizatio... In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is crucial.Still,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical dimensions.These deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s values.The optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization methods.The proposed method better balances all optimization objective functions and reduces the impact of their dimensionality.When the cost of BESS decreases by approximately 30%,its participation deepens by about 1 time.Moreover,if the price of the electrolyzer is less than 15¥/kWh or if the cost of the fuel cell drops below 4¥/kWh,their participation will increase substantially.This study aims to provide a more reasonable approach to solving multi-objective optimization problems. 展开更多
关键词 Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system
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Optimal Control of Unknown Collective Spin Systems via a Neural Network Surrogate
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作者 Yaofeng Chen Li You 《Chinese Physics Letters》 2025年第10期117-128,共12页
Quantum optimal control(QOC)relies on accurately modeling system dynamics and is often challenged by unknown or inaccessible interactions in real systems.Taking an unknown collective spin system as an example,this wor... Quantum optimal control(QOC)relies on accurately modeling system dynamics and is often challenged by unknown or inaccessible interactions in real systems.Taking an unknown collective spin system as an example,this work introduces a machine-learning-based,data-driven scheme to overcome the challenges encountered,with a trained neural network(NN)assuming the role of a surrogate model that captures the system’s dynamics and subsequently enables QOC to be performed on the NN instead of on the real system.The trained NN surrogate proves effective for practical QOC tasks and is further demonstrated to be adaptable to different experimental conditions,remaining robust across varying system sizes and pulse durations. 展开更多
关键词 neural network quantum optimal control surrogate model trained neural network nn assuming quantum optimal control qoc relies collective spin system optimal control captures system s dynamics
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Optimal Lyapunov Function and Minimum Amplitude Control for Disturbed Linear Systems
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作者 Xiuchong Liu Zhanshan Wang 《IEEE/CAA Journal of Automatica Sinica》 2025年第11期2264-2274,共11页
It is a challenging issue to obtain the minimum amplitude control for linear systems subject to amplitudebounded disturbances.The difficulty is how to accurately give the quantitative relationship between the system H... It is a challenging issue to obtain the minimum amplitude control for linear systems subject to amplitudebounded disturbances.The difficulty is how to accurately give the quantitative relationship between the system H∞norm and control parameters.An optimal-Lyapunov-function-based controller design concept is proposed,and a minimum amplitude control scheme is presented under amplitude-bounded disturbances.Firstly,the optimal Lyapunov function is proposed by analyzing the geometric characteristics of the system H∞norm,and the necessary and sufficient condition of the optimal Lyapunov function parameter matrix is given.Secondly,the optimal Lyapunov function parameter matrix is constructed in the parameterized matrix equation,and the accurate quantitative relationship between the system H∞norm and control parameters is given.Finally,the control parameter optimization method is proposed according to the quantitative relationship between the system H∞norm and control parameters.Unlike robust optimization control methods,the presented minimum amplitude control scheme avoids the improper selection of the Lyapunov function in the controller design,and provides a novel way to design the minimum amplitude control under the given control accuracy.A buck converter example is given to illustrate the effectiveness and practicability of the presented scheme. 展开更多
关键词 Geometric analysis of H∞norm linear systems minimum amplitude control optimal Lyapunov function parameter optimization Riccati inequality
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A Sine and Wormhole Energy Whale Optimization Algorithm for Optimal FACTS Placement in Uncertain Wind Integrated Scenario Based Power Systems
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作者 Sunilkumar P.Agrawal Pradeep Jangir +4 位作者 Arpita Sundaram B.Pandya Anil Parmar Ahmad O.Hourani Bhargavi Indrajit Trivedi 《Journal of Bionic Engineering》 2025年第4期2115-2134,共20页
The Sine and Wormhole Energy Whale Optimization Algorithm(SWEWOA)represents an advanced solution method for resolving Optimal Power Flow(OPF)problems in power systems equipped with Flexible AC Transmission System(FACT... The Sine and Wormhole Energy Whale Optimization Algorithm(SWEWOA)represents an advanced solution method for resolving Optimal Power Flow(OPF)problems in power systems equipped with Flexible AC Transmission System(FACTS)devices which include Thyristor-Controlled Series Compensator(TCSC),Thyristor-Controlled Phase Shifter(TCPS),and Static Var Compensator(SVC).SWEWOA expands Whale Optimization Algorithm(WOA)through the integration of sine and wormhole energy features thus improving exploration and exploitation capabilities for efficient convergence in complex non-linear OPF problems.A performance evaluation of SWEWOA takes place on the IEEE-30 bus test system through static and dynamic loading scenarios where it demonstrates better results than five contemporary algorithms:Adaptive Chaotic WOA(ACWOA),WOA,Chaotic WOA(CWOA),Sine Cosine Algorithm Differential Evolution(SCADE),and Hybrid Grey Wolf Optimization(HGWO).The research shows that SWEWOA delivers superior generation cost reduction than other algorithms by reaching a minimum of 0.9%better performance.SWEWOA demonstrates superior power loss performance by achieving(P_(loss,min))at the lowest level compared to all other tested algorithms which leads to better system energy efficiency.The dynamic loading performance of SWEWOA leads to a 4.38%reduction in gross costs which proves its capability to handle different operating conditions.The algorithm achieves top performance in Friedman Rank Test(FRT)assessments through multiple performance metrics which verifies its consistent reliability and strong stability during changing power demands.The repeated simulations show that SWEWOA generates mean costs(C_(gen,min))and mean power loss values(P_(loss,min))with small deviations which indicate its capability to maintain cost-effective solutions in each simulation run.SWEWOA demonstrates great potential as an advanced optimization solution for power system operations through the results presented in this study. 展开更多
关键词 Sine and wormhole energy whale optimization algorithm(SWEWOA) optimal power flow(OPF) Wind integration FACTS devices Power system optimization
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