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The Time-Optimal Problems for Controlled Fuzzy R-Solutions
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作者 Andrej V. Plotnikov Tatyana A. Komleva Irina V. Molchanyuk 《Intelligent Control and Automation》 2011年第2期152-159,共8页
In the present paper, we show the some properties of the fuzzy R-solution of the control linear fuzzy differential inclusions and research the time-optimal problems for it.
关键词 FUZZY DIFFERENTIAL INCLUSIONS control problems time-optimal problems FUZZY R-Solution
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Time-Optimal Control Problem for <i>n</i>×<i>n</i>Co-Operative Parabolic Systems with Control in Initial Conditions
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作者 Mohammed A. Shehata 《Advances in Pure Mathematics》 2013年第9期38-43,共6页
In this paper, time-optimal control problem for a liner n× n co-operative parabolic system involving Laplace operator is considered. This problem is, steering an initial state y(0)=u?, with control u?so that an o... In this paper, time-optimal control problem for a liner n× n co-operative parabolic system involving Laplace operator is considered. This problem is, steering an initial state y(0)=u?, with control u?so that an observation y(t) hitting a given target set in minimum time. First, the existence and uniqueness of solutions of such system under conditions on the coefficients are proved. Afterwards necessary and sufficient conditions of optimality are obtained. Finally a scaler case is given. 展开更多
关键词 time-optimal control problems Bang-Bang controlS PARABOLIC System Co-Operative Systems
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Nonlocal controllability for semilinear problems in Banach spaces
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作者 薛星美 吕忠 《Journal of Southeast University(English Edition)》 EI CAS 2008年第4期541-544,共4页
If A: D(A) X→X is a densely defined and closed linear operator, which generates a linear semigroup S (t) in Banach space X. The nonlocal control/ability for the following nonlocal semilinear problems: u' (t... If A: D(A) X→X is a densely defined and closed linear operator, which generates a linear semigroup S (t) in Banach space X. The nonlocal control/ability for the following nonlocal semilinear problems: u' (t) = Au (t) + Bx( t) + f( t, u(t) ), 0≤t ≤ T with nonlocal initial condition u(0) = u0 + g(u) is discussed in Banach space X. The results show that if semigroup S(t) is strongly continuous, the functionsf and g are compact and the control B is bounded, then it is nonlocally controllable. The nonlocal controllability for the above nonlocal problem is also studied when B and W are unbounded and the semigroup S(t) is compact or strongly continuous. For illustration, a partial differential equation is worked out. 展开更多
关键词 nonlocal problem nonlocal controllability mild solution completely continuous
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Solving the Optimal Control Problems of Nonlinear Duffing Oscillators By Using an Iterative Shape Functions Method 被引量:2
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作者 Cheinshan Liu Chunglun Kuo Jiangren Chang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第1期33-48,共16页
In the optimal control problem of nonlinear dynamical system,the Hamiltonian formulation is useful and powerful to solve an optimal control force.However,the resulting Euler-Lagrange equations are not easy to solve,wh... In the optimal control problem of nonlinear dynamical system,the Hamiltonian formulation is useful and powerful to solve an optimal control force.However,the resulting Euler-Lagrange equations are not easy to solve,when the performance index is complicated,because one may encounter a two-point boundary value problem of nonlinear differential algebraic equations.To be a numerical method,it is hard to exactly preserve all the specified conditions,which might deteriorate the accuracy of numerical solution.With this in mind,we develop a novel algorithm to find the solution of the optimal control problem of nonlinear Duffing oscillator,which can exactly satisfy all the required conditions for the minimality of the performance index.A new idea of shape functions method(SFM)is introduced,from which we can transform the optimal control problems to the initial value problems for the new variables,whose initial values are given arbitrarily,and meanwhile the terminal values are determined iteratively.Numerical examples confirm the high-performance of the iterative algorithms based on the SFM,which are convergence fast,and also provide very accurate solutions.The new algorithm is robust,even large noise is imposed on the input data. 展开更多
关键词 Nonlinear Duffing oscillator optimal control problem Hamiltonian formulation shape functions method iterative algorithm
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Parametric Iteration Method for Solving Linear Optimal Control Problems 被引量:1
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作者 Abdolsaeed Alavi Aghileh Heidari 《Applied Mathematics》 2012年第9期1059-1064,共6页
This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of func... This article presents the Parametric Iteration Method (PIM) for finding optimal control and its corresponding trajectory of linear systems. Without any discretization or transformation, PIM provides a sequence of functions which converges to the exact solution of problem. Our emphasis will be on an auxiliary parameter which directly affects on the rate of convergence. Comparison of PIM and the Variational Iteration Method (VIM) is given to show the preference of PIM over VIM. Numerical results are given for several test examples to demonstrate the applicability and efficiency of the method. 展开更多
关键词 PARAMETRIC ITERATION METHOD Optimal control problem Pontryagin’s Maximum Principle He’s VARIATIONAL ITERATION METHOD
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Data-Driven Learning Control Algorithms for Unachievable Tracking Problems 被引量:1
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作者 Zeyi Zhang Hao Jiang +1 位作者 Dong Shen Samer S.Saab 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期205-218,共14页
For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to in... For unachievable tracking problems, where the system output cannot precisely track a given reference, achieving the best possible approximation for the reference trajectory becomes the objective. This study aims to investigate solutions using the Ptype learning control scheme. Initially, we demonstrate the necessity of gradient information for achieving the best approximation.Subsequently, we propose an input-output-driven learning gain design to handle the imprecise gradients of a class of uncertain systems. However, it is discovered that the desired performance may not be attainable when faced with incomplete information.To address this issue, an extended iterative learning control scheme is introduced. In this scheme, the tracking errors are modified through output data sampling, which incorporates lowmemory footprints and offers flexibility in learning gain design.The input sequence is shown to converge towards the desired input, resulting in an output that is closest to the given reference in the least square sense. Numerical simulations are provided to validate the theoretical findings. 展开更多
关键词 Data-driven algorithms incomplete information iterative learning control gradient information unachievable problems
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Convergence and Superconvergence of Fully Discrete Finite Element for Time Fractional Optimal Control Problems 被引量:1
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作者 Yuelong Tang 《American Journal of Computational Mathematics》 2021年第1期53-63,共11页
In this paper, we consider a fully discrete finite element approximation for time fractional optimal control problems. The state and adjoint state are approximated by triangular linear fi nite elements in space and &l... In this paper, we consider a fully discrete finite element approximation for time fractional optimal control problems. The state and adjoint state are approximated by triangular linear fi nite elements in space and <em>L</em>1 scheme in time. The control is obtained by the variational discretization technique. The main purpose of this work is to derive the convergence and superconvergence. A numerical example is presented to validate our theoretical results. 展开更多
关键词 Time Fractional Optimal control problems Finite Element Convergence and Superconvergence
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Problems and Strategies in Applications of Advanced Process Control in China
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作者 Luo Xionglin Zuo Xin 《Petroleum Science》 SCIE CAS CSCD 2005年第3期44-49,共6页
Advanced Process Control (APC) is necessary for oil refining and chemical process in China, but some problems have emerged in the application of APC techniques in this field. This paper discusses the conditions of A... Advanced Process Control (APC) is necessary for oil refining and chemical process in China, but some problems have emerged in the application of APC techniques in this field. This paper discusses the conditions of APC application concerning process design, distributed control system (DCS) choice and regular control. It analyzes the problems and strategies in APC application. Some suggestions are proposed for the enterprise to benefit from APC application. 展开更多
关键词 China petrochemical process advanced process control application problem STRATEGY
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TIME AND NORM OPTIMAL CONTROLS:A SURVEY OF RECENT RESULTS AND OPEN PROBLEMS
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作者 H. O. Fattorini 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2203-2218,共16页
We present in this paper a survey of recent results on the relation between time and norm optimality for linear systems and the infinite dimensional version of Pontryagin's maximum principle. In particular, we discus... We present in this paper a survey of recent results on the relation between time and norm optimality for linear systems and the infinite dimensional version of Pontryagin's maximum principle. In particular, we discuss optimality (or nonoptimality) of singular controls satisfying the maximum principle and smoothness of the costate in function of smoothness of the target. 展开更多
关键词 linear control systems in Banach spaces time optimal problem norm optimal problem
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Time-optimal control for hybrid systems based on the nitrogen-vacancy center
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作者 Shanping YU Na LI +1 位作者 Peng WEI Zairong XI 《Control Theory and Technology》 EI CSCD 2017年第3期219-225,共7页
Fast and high fidelity quantum control is the key technology of quantum computing. The hybrid system composed of the nitrogen-vacancy center and nearby Carbon-13 nuclear spin is expected to solve this problem. The nit... Fast and high fidelity quantum control is the key technology of quantum computing. The hybrid system composed of the nitrogen-vacancy center and nearby Carbon-13 nuclear spin is expected to solve this problem. The nitrogen-vacancy center electron spin enables fast operations for its strong coupling to the control field, whereas the nuclear spins preserve the coherence for their weak coupling to the environment. In this paper, we describe a strategy to achieve time-optimal control of the Carbon-13 nuclear spin qubit by alternating controlling the nitrogen-vacancy center electron spin as an actuator. We transform the qubit gate operation into a switched system. By using the maximum principle, we study the minimum time control of the switched system and obtain the time-optimal control of the qubit gate operation. We show that the X gate and Y gate operations are within 10μs while the fidelity reaches 0.995. 展开更多
关键词 time-optimal control nitrogen-vacancy center qubit gate operations switched system
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Iterative Solution Methods for a Class of State and Control Constrained Optimal Control Problems
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作者 Erkki Laitinen Alexander Lapin 《Applied Mathematics》 2012年第12期1862-1867,共6页
Iterative methods for solving discrete optimal control problems are constructed and investigated. These discrete problems arise when approximating by finite difference method or by finite element method the optimal co... Iterative methods for solving discrete optimal control problems are constructed and investigated. These discrete problems arise when approximating by finite difference method or by finite element method the optimal control problems which contain a linear elliptic boundary value problem as a state equation, control in the righthand side of the equation or in the boundary conditions, and point-wise constraints for both state and control functions. The convergence of the constructed iterative methods is proved, the implementation problems are discussed, and the numerical comparison of the methods is executed. 展开更多
关键词 CONSTRAINED Optimal control problem SADDLE Point problem Finite Element Method ITERATIVE Algorithm
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Realization of high-fidelity and robust geometric gates with time-optimal control technique in superconducting quantum circuit
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作者 王治旻 马壮 +9 位作者 喻祥敏 郑文 周坤 张宇佳 张钰 兰栋 赵杰 谭新生 李邵雄 于扬 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期205-209,共5页
One of the key features required to realize fault-tolerant quantum computation is the robustness of quantum gates against errors.Since geometric quantum gate is naturally insensitivity to noise,it appears to be a prom... One of the key features required to realize fault-tolerant quantum computation is the robustness of quantum gates against errors.Since geometric quantum gate is naturally insensitivity to noise,it appears to be a promising routine to achieve high-fidelity,robust quantum gates.The implementation of geometric quantum gate however faces some troubles such as its complex interaction among multiple energy levels.Moreover,traditional geometric schemes usually take more time than equivalent dynamical ones.Here,we experimentally demonstrate a geometric gate scheme with the time-optimal control(TOC)technique in a superconducting quantum circuit.With a transmon qubit and operations restricted to two computational levels,we implement a set of geometric gates which exhibit better robustness features against control errors than the dynamical counterparts.The measured fidelities of TOC X gate and X/2 gate are 99.81%and 99.79%respectively.Our work shows a promising routine toward scalable fault-tolerant quantum computation. 展开更多
关键词 superconducting qubits geometric quantum computation time-optimal control
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SEQUENTIAL QUADRATIC PROGRAMMING METHODS FOR OPTIMAL CONTROL PROBLEMS WITH STATE CONSTRAINTS
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作者 徐成贤 Jong de J. L. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1993年第2期163-174,共12页
A kind of direct methods is presented for the solution of optimal control problems with state constraints. These methods are sequential quadratic programming methods. At every iteration a quadratic programming which i... A kind of direct methods is presented for the solution of optimal control problems with state constraints. These methods are sequential quadratic programming methods. At every iteration a quadratic programming which is obtained by quadratic approximation to Lagrangian function and linear approximations to constraints is solved to get a search direction for a merit function. The merit function is formulated by augmenting the Lagrangian function with a penalty term. A line search is carried out along the search direction to determine a step length such that the merit function is decreased. The methods presented in this paper include continuous sequential quadratic programming methods and discreate sequential quadratic programming methods. 展开更多
关键词 Optimal control problems with State Constraints Sequential Quadratic Programming Lagrangian Function. Merit Function Line Search.
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The Similar Structures and Control Problems of Complex Systems 被引量:1
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作者 张嗣瀛 《系统仿真学报》 CAS CSCD 2002年第11期1455-1457,共3页
In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between t... In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between the functions and behaviors of these systems and their similar structures will be studied. Owing to the management of social systems and the course of evolution of biotic systems may be regarded as control processes, the researches will be within the scope of control problems. Moreover, since it is difficult to model for biotic and social systems, it will start with the control problems of complex systems, possessing similar structures, in engineering. The obtained results show that for either linear or nonlinear systems and for a lot of control problems similar structures lead to a series of simplifications. In general, the original system may be decomposed into reduced amount of subsystems with lower dimensions and simpler structures. By virtue of such subsystems, the control problems of original system can be solved more simply. At last, it turns round to observe the biotic and social systems and some analyses are given. 展开更多
关键词 复杂系统 相似结构 可控制性
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Linear Problems of Optimal Control of Fuzzy Maps
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作者 Andrej V. PLOTNIKOV Tatyana A. KOMLEVA 《Intelligent Information Management》 2009年第3期139-144,共6页
In the present paper, we show the some properties of the fuzzy R-solution of the control linear fuzzy differential inclusions and research the optimal time problems for it.
关键词 FUZZY DIFFERENTIAL INCLUSIONS control problems
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Iterative Solution of Mesh Constrained Optimal Control Problems with Two-Level Mesh Approximations of Parabolic State Equation
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作者 A. Lapin E. Laitinen 《Journal of Applied Mathematics and Physics》 2018年第1期58-68,共11页
We consider a linear-quadratical optimal control problem of a system governed by parabolic equation with distributed in right-hand side control and control and state constraints. We construct a mesh approximation of t... We consider a linear-quadratical optimal control problem of a system governed by parabolic equation with distributed in right-hand side control and control and state constraints. We construct a mesh approximation of this problem using different two-level approximations of the state equation, ADI and fractional steps approximations in time among others. Iterative solution methods are investigated for all constructed approximations of the optimal control problem. Their implementation can be carried out in parallel manner. 展开更多
关键词 PARABOLIC Optimal control State Constraints Finite Difference METHOD CONSTRAINED SADDLE Point problem Iterative METHOD
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A BICUBIC B-SPLINE FINITE ELEMENT METHOD FOR FOURTH-ORDER SEMILINEAR PARABOLIC OPTIMAL CONTROL PROBLEMS
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作者 Fangfang DU Tongjun SUN 《Acta Mathematica Scientia》 SCIE CSCD 2024年第6期2411-2421,共11页
A bicubic B-spline finite element method is proposed to solve optimal control problems governed by fourth-order semilinear parabolic partial differential equations.Its key feature is the selection of bicubic B-splines... A bicubic B-spline finite element method is proposed to solve optimal control problems governed by fourth-order semilinear parabolic partial differential equations.Its key feature is the selection of bicubic B-splines as trial functions to approximate the state and costate variables in two space dimensions.A Crank-Nicolson difference scheme is constructed for time discretization.The resulting numerical solutions belong to C2in space,and the order of the coefficient matrix is low.Moreover,the Bogner-Fox-Schmit element is considered for comparison.Two numerical experiments demonstrate the feasibility and effectiveness of the proposed method. 展开更多
关键词 bicubic B-spline finite element method optimal control problem Bogner-Fox-Schmit element Crank-Nicolson scheme numerical experiment
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Linear Control Problems of the Fuzzy Maps
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作者 Andrej V. Plotnikov Tatyana A. Komleva Irina V. Molchanyuk 《Journal of Software Engineering and Applications》 2010年第3期191-197,共7页
In the present paper, we show the some properties of the fuzzy R-solution of the control linear fuzzy differential inclu-sions and research the optimal time problems for it.
关键词 FUZZY DIFFERENTIAL INCLUSIONS control problems
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Global Optimization for Solving Linear Non-Quadratic Optimal Control Problems
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作者 Jinghao Zhu 《Journal of Applied Mathematics and Physics》 2016年第10期1859-1869,共11页
This paper presents a global optimization approach to solving linear non-quadratic optimal control problems. The main work is to construct a differential flow for finding a global minimizer of the Hamiltonian function... This paper presents a global optimization approach to solving linear non-quadratic optimal control problems. The main work is to construct a differential flow for finding a global minimizer of the Hamiltonian function over a Euclid space. With the Pontryagin principle, the optimal control is characterized by a function of the adjoint variable and is obtained by solving a Hamiltonian differential boundary value problem. For computing an optimal control, an algorithm for numerical practice is given with the description of an example. 展开更多
关键词 Linear Non-Quadratic Optimal control Pontryagin Principle Global Optimization Hamiltonian Differential Boundary Value problem
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Problems and Measures in Internal Control and Risk Management of Drug Research and Development Enterprises
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作者 Jun Liu 《Proceedings of Business and Economic Studies》 2019年第6期7-12,共6页
The internal control and risk managementof drug research and development enterprises directlyaffects the survival and development of enterprises.With the development of information technologyand the integration with t... The internal control and risk managementof drug research and development enterprises directlyaffects the survival and development of enterprises.With the development of information technologyand the integration with the global economy,pharmaceutical companies are able to achieve moreachievements in development while facing increasingcompetitive pressures. Finance is a pivotal spine of acompany’s development. If the internal control andrisk management of a company are not complete andcomprehensive, the enterprise will inevitably turn intoa crisis. Therefore, it is necessary to strengthen theanalysis of the problems in the internal control andrisk management of drug research and developmententerprises, and propose corresponding solutions. 展开更多
关键词 DRUG research and development ENTERPRISE INTERNAL control Risk management problems Measures
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