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Existence and Uniqueness Results for a Fully Third-Order Boundary Value Problem
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作者 Xiaoming Liu Yongxiang Li 《Advances in Pure Mathematics》 2023年第8期495-503,共14页
The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have stud... The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained. 展开更多
关键词 fully Third-order BVP SOLUTION Positive Solution Existence and Uniqueness Inequality Conditions
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SHARP ESTIMATES OF ALL HOMOGENEOUS EXPANSIONS FOR A SUBCLASS OF QUASI-CONVEX MAPPINGS OF TYPE B AND ORDER α IN SEVERAL COMPLEX VARIABLES 被引量:1
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作者 刘小松 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1804-1818,共15页
In this article, first, the sharp estimates of all homogeneous expansions for a subclass of quasi-convex mappings of type B and order B on the unit ball in complex Ba- nach spaces are given. Second, the sharp estimat... In this article, first, the sharp estimates of all homogeneous expansions for a subclass of quasi-convex mappings of type B and order B on the unit ball in complex Ba- nach spaces are given. Second, the sharp estimates of all homogeneous expansions for the above generalized mappings on the unit polydisk in (in are also established. In particular, the sharp estimates of all homogeneous expansions for a subclass of quasi-convex mappings (include quasi-convex mappings of type A and quasi-convex mappings of type B) in several complex variables are get accordingly. Our results state that a weak version of the Bieber- bach conjecture for quasi-convex mappings of type B and order a in several complex variables is proved, and the derived conclusions are the generalization of the classical results in one complex variable. 展开更多
关键词 homogeneous expansion quasi-convex mapping of type B and order a quasi-convex mapping quasi-convex mapping of type A quasi-convex mapping oftype B
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SHARP ESTIMATES OF QUASI-CONVEX MAPPINGS OF TYPE B AND ORDER α 被引量:2
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作者 Mingsheng LIU Fen WU Yan YANG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第5期1265-1276,共12页
In this paper,we first establish several sharp inequalities of homogeneous expansion for biholomorphic quasi-convex mappings of type B and order a on the unit ball E in a complex Banach space X by applying the method ... In this paper,we first establish several sharp inequalities of homogeneous expansion for biholomorphic quasi-convex mappings of type B and order a on the unit ball E in a complex Banach space X by applying the method and technique of complex analysis.Then,as the application of these sharp inequalities,we derive the sharp estimate of third homogeneous expansions for the above mappings defined on the unit polydisk U^n in C^n. 展开更多
关键词 quasi-convex MAPPINGS of TYPE B and order α INEQUALITIES of HOMOGENEOUS EXPANSIONS the SHARP estimate of third HOMOGENEOUS EXPANSIONS
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The Ellipsoidal Invariant Set of Fractional Order Systems Subject to Actuator Saturation:The Convex Combination Form 被引量:1
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作者 Kai Chen Junguo Lu Chuang Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期311-319,共9页
The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper,... The domain of attraction of a class of fractional order systems subject to saturating actuators is investigated in this paper. We show the domain of attraction is the convex hull of a set of ellipsoids. In this paper, the Lyapunov direct approach and fractional order inequality are applied to estimating the domain of attraction for fractional order systems subject to actuator saturation. We demonstrate that the convex hull of ellipsoids can be made invariant for saturating actuators if each ellipsoid with a bounded control of the saturating actuators is invariant. The estimation on the contractively invariant ellipsoid and construction of the continuous feedback law are derived in terms of linear matrix inequalities (LMIs). Two numerical examples illustrate the effectiveness of the developed method. © 2014 Chinese Association of Automation. 展开更多
关键词 ALGEBRA Computational geometry Linear matrix inequalities Numerical methods Saturation (materials composition)
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ON FULLY CONVEX AND LOCALLY FULLY CONVEX BANACH SPACE*
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作者 那启元 《Acta Mathematica Scientia》 SCIE CSCD 1990年第3期327-343,共17页
In this paper, we introduce the concept of locally fully convexity. We study the properties of fully convex and locally fully convex Banach spaces and the relations between them. We also give some applications of the ... In this paper, we introduce the concept of locally fully convexity. We study the properties of fully convex and locally fully convex Banach spaces and the relations between them. We also give some applications of the fully convex and locally fully convex Banach spaces. 展开更多
关键词 LFC TH LIM ON fully convex AND LOCALLY fully convex BANACH SPACE
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On a subclass of bi-univalent functions defined by convex combination of order α with the Faber polynomial expansion
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作者 Wurenqiqige LI Shu-hai Tsedenbayar Dashdondog 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期278-286,共9页
In this paper,we define new subclasses of bi-univalent functions involving a differ-ential operator in the open unit disc△={z:z∈C and|z|<1}:Moreover,we use the Faber polynomial expansion to obtain the bounds of t... In this paper,we define new subclasses of bi-univalent functions involving a differ-ential operator in the open unit disc△={z:z∈C and|z|<1}:Moreover,we use the Faber polynomial expansion to obtain the bounds of the coefficients for functions belong to the subclasses. 展开更多
关键词 bi-univalent functions convex combination Faber polynomial expansion coefficient bounds su bordination combination of orderα
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Maximal Above and Below Pairs of Abelian Fully Ordered Groups
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作者 郑熙强 《Northeastern Mathematical Journal》 CSCD 2000年第4期445-450,共6页
In this paper, maximal above and below pairs of fully ordered groups (o groups) are studied. It is shown that maximal above and below pairs of an divisible abelian o group have some specific properties, and by using... In this paper, maximal above and below pairs of fully ordered groups (o groups) are studied. It is shown that maximal above and below pairs of an divisible abelian o group have some specific properties, and by using these properties another embedding method of an abelian o group to real valued functions is discussed. 展开更多
关键词 ordered group convex subgroup above and below subgroup
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On a-order-convexity of Fuzzy Syntopogenous Spaces
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作者 WANG Hong 《现代电子技术》 2007年第1期179-181,共3页
In this paper,we combine L-fuzzy syntopogenous structure on X with algebraic structure on X.First,the *-increasing and *-decreasing spaces have been studied.Second,we define a-order-convexity on syntopogenous structur... In this paper,we combine L-fuzzy syntopogenous structure on X with algebraic structure on X.First,the *-increasing and *-decreasing spaces have been studied.Second,we define a-order-convexity on syntopogenous structures(X,S,≤).some important properties of a-order-convexity have been obtained. 展开更多
关键词 模糊拓扑学 代数结构 一阶凸性 模糊拓扑空间
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Higher-Order Minimizers and Generalized (F,<i>ρ</i>)-Convexity in Nonsmooth Vector Optimization over Cones
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作者 S. K. Suneja Sunila Sharma Malti Kapoor 《Applied Mathematics》 2015年第1期7-19,共13页
In this paper, we introduce the concept of a (weak) minimizer of order k for a nonsmooth vector optimization problem over cones. Generalized classes of higher-order cone-nonsmooth (F, ρ)-convex functions are introduc... In this paper, we introduce the concept of a (weak) minimizer of order k for a nonsmooth vector optimization problem over cones. Generalized classes of higher-order cone-nonsmooth (F, ρ)-convex functions are introduced and sufficient optimality results are proved involving these classes. Also, a unified dual is associated with the considered primal problem, and weak and strong duality results are established. 展开更多
关键词 NONSMOOTH Vector Optimization OVER CONES (Weak) MINIMIZERS of order k NONSMOOTH (F ρ)-convex Function of order k
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Fast First-Order Methods for Minimizing Convex Composite Functions
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作者 Qipeng Li Hongwei Liu Zexian Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第6期46-52,共7页
Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ ... Two new versions of accelerated first-order methods for minimizing convex composite functions are proposed. In this paper, we first present an accelerated first-order method which chooses the step size 1/ Lk to be 1/ L0 at the beginning of each iteration and preserves the computational simplicity of the fast iterative shrinkage-thresholding algorithm. The first proposed algorithm is a non-monotone algorithm. To avoid this behavior, we present another accelerated monotone first-order method. The proposed two accelerated first-order methods are proved to have a better convergence rate for minimizing convex composite functions. Numerical results demonstrate the efficiency of the proposed two accelerated first-order methods. 展开更多
关键词 first-order method iterative shrinkage-thresholding algorithm convex programming adaptive restart composite functions.
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On new classes of strongly Janowski type functions of complex order
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作者 Khalil Ahmad Khudija Bibi M.Sajjad Shabbir 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期89-99,共11页
We investigate some new subclasses of analytic functions of Janowski type of complex order.We also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the functions.Moreover,an... We investigate some new subclasses of analytic functions of Janowski type of complex order.We also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the functions.Moreover,analytic properties of these classes under certain integral operator are also discussed.Our findings are more comprehensive than the existing results in the literature. 展开更多
关键词 SUBORDINATION Janowski function starlike function convex function complex order
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A higher-order porous thermoelastic problem with microtemperatures
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作者 J.R.FERNáNDEZ R.QUINTANILLA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第11期1911-1926,共16页
In this paper,we study a porous thermoelastic problem with microtemperatures assuming parabolic higher order in time derivatives for the thermal variables.The model is derived and written as a coupled linear system.Th... In this paper,we study a porous thermoelastic problem with microtemperatures assuming parabolic higher order in time derivatives for the thermal variables.The model is derived and written as a coupled linear system.Then,a uniqueness result is proved by using the logarithmic convexity method in the case that we do not assume that the mechanical energy is positive definite.Finally,the existence of the solution is obtained by introducing an energy function and applying the theory of linear semigroups. 展开更多
关键词 higher order THERMOELASTICITY microtemperature logarithmic convexity method existence and uniqueness
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Multiple Solutions for a Class of Variable-Order Fractional Laplacian Equations with Concave-Convex Nonlinearity
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作者 Canlin Gan Ting Xiao Qiongfen Zhang 《Journal of Applied Mathematics and Physics》 2022年第3期837-849,共13页
This paper is concerned with the following variable-order fractional Laplacian equations , where N ≥ 1 and N > 2s(x,y) for (x,y) ∈ Ω × Ω, Ω is a bounded domain in R<sup>N</sup>, s(&#8901;)... This paper is concerned with the following variable-order fractional Laplacian equations , where N ≥ 1 and N > 2s(x,y) for (x,y) ∈ Ω × Ω, Ω is a bounded domain in R<sup>N</sup>, s(&#8901;) ∈ C (R<sup>N</sup> × R<sup>N</sup>, (0,1)), (-Δ)<sup>s(&#8901;)</sup> is the variable-order fractional Laplacian operator, λ, μ > 0 are two parameters, V: Ω → [0, ∞) is a continuous function, f ∈ C(Ω × R) and q ∈ C(Ω). Under some suitable conditions on f, we obtain two solutions for this problem by employing the mountain pass theorem and Ekeland’s variational principle. Our result generalizes the related ones in the literature. 展开更多
关键词 Concave-convex Nonlinearity Variable-order Fractional Laplacian Variational Methods Fractional Elliptic Equation
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The Second-Order Differential Equation System with the Feedback Controls for Solving Convex Programming
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作者 Xingxu Chen Li Wang +1 位作者 Juhe Sun Yanhong Yuan 《Open Journal of Applied Sciences》 2022年第6期977-989,共13页
In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent opera... In this paper, we establish the second-order differential equation system with the feedback controls for solving the problem of convex programming. Using Lagrange function and projection operator, the equivalent operator equations for the convex programming problems under the certain conditions are obtained. Then a second-order differential equation system with the feedback controls is constructed on the basis of operator equation. We prove that any accumulation point of the trajectory of the second-order differential equation system with the feedback controls is a solution to the convex programming problem. In the end, two examples using this differential equation system are solved. The numerical results are reported to verify the effectiveness of the second-order differential equation system with the feedback controls for solving the convex programming problem. 展开更多
关键词 convex Programming Lagrange Function Projection Operator Second-order Differential Equation
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基于凸包理论的含风电电力系统负荷恢复方案优化 被引量:1
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作者 伊昆明 孙磊 +1 位作者 丁江 丁明 《电力系统自动化》 EI CSCD 北大核心 2024年第5期77-87,共11页
大停电事故后,合理的负荷恢复策略对加快电力系统恢复、减少停电损失具有重要意义。针对标准交流潮流方程的非凸性导致负荷恢复模型求解效率低的问题,提出了基于凸包理论的含风电电力系统负荷恢复方案优化方法。首先,简要介绍了凸包理... 大停电事故后,合理的负荷恢复策略对加快电力系统恢复、减少停电损失具有重要意义。针对标准交流潮流方程的非凸性导致负荷恢复模型求解效率低的问题,提出了基于凸包理论的含风电电力系统负荷恢复方案优化方法。首先,简要介绍了凸包理论以及非线性函数的凸包构建方法。其次,针对风电出力的不确定性,采用条件风险价值理论处理风电波动带来的风险,进而建立了直角坐标系下基于凸包理论的电力系统负荷恢复二阶锥优化模型,其中,交流潮流方程中的非线性项采用凸包表达。针对无法精确确定凸包参数的问题,提出了基于迭代更新的参数优化方法,减少因凸包引入的松弛误差。所提出的模型为混合整数二阶锥规划模型,可采用商业求解器高效求解。最后,采用IEEE 39节点系统和改进的广东电力系统验证了所提出模型的有效性。 展开更多
关键词 电力系统 风电 潮流 负荷恢复 凸包理论 直角坐标 混合整数二阶锥规划
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RSS和AOA融合的单站低空无线电辐射源定位算法
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作者 戎俊樵 仇洪冰 李燕龙 《计算机应用与软件》 北大核心 2024年第8期126-131,174,共7页
提出一种在低空场景下基于接收信号强度(Rcecived Signal Strength,RSS)与到达角度(Angle of Arrival,AOA)信息融合的单站无源定位算法。该算法采用单架无人机设备虚拟多站设备接收无线电辐射源信号,融合RSS估计的距离信息与AOA方向角信... 提出一种在低空场景下基于接收信号强度(Rcecived Signal Strength,RSS)与到达角度(Angle of Arrival,AOA)信息融合的单站无源定位算法。该算法采用单架无人机设备虚拟多站设备接收无线电辐射源信号,融合RSS估计的距离信息与AOA方向角信息,依据最小二乘准则(LS)构造算法的优化目标函数,采用凸松弛技术将目标函数等价为二阶锥规划(SOCP)问题并通过内点法求解。实验结果表明,该算法的定位精度在2 km范围内可达20 m,其定位性能优于单站无源定位算法,且由于采用单架无人机采集信号,其设备复杂度相较于多站无源定位较低。 展开更多
关键词 室外定位 接收信号强度 到达角度 二阶锥规划 凸松弛技术
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高次凸非球面补偿检验方法研究
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作者 陈光宇 胡明勇 +4 位作者 杨传龙 封志伟 徐剑锋 白茜 崔金龙 《量子电子学报》 CAS CSCD 北大核心 2024年第1期57-66,共10页
高次凸非球面镜是光学系统中至关重要的元件,通常作为次镜来补偿光学系统的轴外像差,但其检验方法一直是一大难点。基于背向零位检测方法,提出利用三透镜与单折射面组合的形式来补偿高次非球面的法线像差。首先选取高次非球面的二次比... 高次凸非球面镜是光学系统中至关重要的元件,通常作为次镜来补偿光学系统的轴外像差,但其检验方法一直是一大难点。基于背向零位检测方法,提出利用三透镜与单折射面组合的形式来补偿高次非球面的法线像差。首先选取高次非球面的二次比较面来简化计算,基于三级像差理论求解系统的初始结构,对高次非球面的法线像差进行补偿,使用ZEMAX软件仿真与优化后,设计结果完全满足要求。随后结合一块有效通光口径为170 mm、顶点曲率半径为266.8 mm的高次凸非球面反射镜,测得镜面的面形精度均方根为0.019λ(λ=632.8 nm),满足实际检测要求,验证了所提设计方法的可行性。此方法为大口径高次凸非球面的检验提供了一个新的思路。 展开更多
关键词 几何光学 高次凸非球面 零位补偿 三级像差
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基于双凹凸变换的高阶模糊认知图天然气消费预测
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作者 王青青 骆正山 +1 位作者 高懿琼 王晓敏 《运筹与管理》 CSCD 北大核心 2024年第4期206-211,I0075-I0081,共13页
为解决高阶模糊认知图难以处理一维时间序列预测问题,提出基于双凹凸变换的高阶模糊认知图。为增加数据维度,采用特定函数对一维时间序列作凹凸变换,其次为改善高阶模糊认知图非线性表达能力,设计了具有凹凸特征的新传递函数,并结合全国... 为解决高阶模糊认知图难以处理一维时间序列预测问题,提出基于双凹凸变换的高阶模糊认知图。为增加数据维度,采用特定函数对一维时间序列作凹凸变换,其次为改善高阶模糊认知图非线性表达能力,设计了具有凹凸特征的新传递函数,并结合全国及30个省份的2000—2019年天然气消费数据进行实证分析。结果表明,在对数据作增维凹凸变换基础上,采用新设计传递函数的高阶模糊认知图和基于传统传递函数的高阶模糊认知图预测结果相比更优,新传递函数适用率高达96.4%;其次将其两者预测结果和ARIMA及GM(1,1)相比,得出所提方法的适用率可达87.1%,进一步验证了提出方法的有效性。 展开更多
关键词 双凹凸变换 高阶模糊认知图 天然气消费预测
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计及压缩机运行域的动态最优电-气能流凸化算法
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作者 陈飞雄 郑翔昊 +2 位作者 邵振国 林勇棋 颜熙颖 《中国电机工程学报》 EI CSCD 北大核心 2024年第14期5548-5561,I0009,共15页
压缩机是电-气互联系统的关键元件,其运行工作点是否位于运行域内关系到系统的安全稳定运行,同时其模型非凸性大幅增加了最优电-气能流的求解难度。为此,该文在压缩机准确建模的基础上,针对电力和天然气系统迥异的传输特性,提出一种计... 压缩机是电-气互联系统的关键元件,其运行工作点是否位于运行域内关系到系统的安全稳定运行,同时其模型非凸性大幅增加了最优电-气能流的求解难度。为此,该文在压缩机准确建模的基础上,针对电力和天然气系统迥异的传输特性,提出一种计及压缩机运行域的动态最优电-气能流凸化算法。首先,根据压缩机运行参数与状态变量间的映射关系,构建压缩机三维运行域模型,并利用超平面实现运行域的凸包络松弛。其次,考虑差异化传输特性建立动态最优电-气能流模型,实现模型的混合整数二阶锥凸重构,并提出一种基于动态线性化与紧缩凸包络的凸化算法。最后,算例验证所提模型的有效性,表明所提算法在计算精度和效率上均优于连续锥规划算法。 展开更多
关键词 电-气互联系统 最优电-气能流 压缩机运行域 凸包络 二阶锥松弛
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基于全驱系统方法的高阶严反馈系统时变输出约束控制
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作者 蔡光斌 肖永强 +2 位作者 胡昌华 杨小冈 凡永华 《自动化学报》 EI CAS CSCD 北大核心 2024年第2期372-385,共14页
针对输出受不对称时变约束的不确定高阶严反馈系统,提出一种基于全驱系统方法的高阶自适应动态面输出约束控制方法.所研究的高阶严反馈系统,每个子系统都是高阶形式,通过非线性转换函数将原输出约束系统转换为新的无约束系统,从而将原... 针对输出受不对称时变约束的不确定高阶严反馈系统,提出一种基于全驱系统方法的高阶自适应动态面输出约束控制方法.所研究的高阶严反馈系统,每个子系统都是高阶形式,通过非线性转换函数将原输出约束系统转换为新的无约束系统,从而将原系统输出约束问题转化为新系统输出有界的问题.进一步结合全驱系统方法和自适应动态面控制,直接将每个高阶子系统作为一个整体进行控制器设计,而不需要将其转化为一阶系统形式,有效简化了设计步骤;同时通过引入一系列低通滤波器来获得虚拟控制律的高阶导数,以代替复杂的微分运算.基于Lyapunov稳定性理论证明闭环系统所有信号是一致最终有界的,系统输出在满足约束的条件下能有效跟踪期望的参考信号,且可通过调整参数使得系统跟踪误差收敛到零附近的足够小的邻域内.最后,通过对柔性关节机械臂系统进行仿真,验证了所提出控制方法的有效性. 展开更多
关键词 全驱系统方法 高阶严反馈系统 时变输出约束 非线性转换函数 自适应动态面控制
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