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基于LMI的二自由度飞行器多变量控制
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作者 高兴泉 范砚策 郭峰 《自动化应用》 2024年第3期63-68,共6页
针对二自由度飞行器存在非线性特性、强耦合性以及易受外界干扰等问题,提出了基于LMI的二自由度飞行器多变量控制方法。首先,根据二自由度飞行器系统的输入和输出变量,结合空间动力学方程建立了系统的状态空间模型;其次,设计满足静态输... 针对二自由度飞行器存在非线性特性、强耦合性以及易受外界干扰等问题,提出了基于LMI的二自由度飞行器多变量控制方法。首先,根据二自由度飞行器系统的输入和输出变量,结合空间动力学方程建立了系统的状态空间模型;其次,设计满足静态输出反馈稳定的多变量控制律;然后,通过李亚普托夫稳定性定理与极点配置法,将控制系统稳定性问题转化为优化问题,利用线性矩阵不等式(LMI)求解满足最优性能指标的多变量控制器参数;最后,通过对比仿真分析与单变量PID,表明该方法能有效提升二自由度飞行器的轨迹跟踪精度。 展开更多
关键词 二自由度飞行器 多变量系统 lmi优化 控制器参数整定
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THE LOGARITHMIC SOBOLEV INEQUALITY FOR A SUBMANIFOLD IN MANIFOLDS WITH ASYMPTOTICALLY NONNEGATIVE SECTIONAL CURVATURE
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作者 东瑜昕 林和子 陆琳根 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期189-194,共6页
In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality... In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature. 展开更多
关键词 asymptotically nonnegative sectional curvature logarithmic Sobolev inequality ABP method
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Weak and Strong Convergence of Self Adaptive Inertial Subgradient Extragradient Algorithms for Solving Variational Inequality Problems
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作者 Yao Li Hongwei Liu Jiamin Lv 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期38-49,共12页
Many solutions of variational inequalities have been proposed,among which the subgradient extragradient method has obvious advantages.Two different algorithms are given for solving variational inequality problem in th... Many solutions of variational inequalities have been proposed,among which the subgradient extragradient method has obvious advantages.Two different algorithms are given for solving variational inequality problem in this paper.The problem we study is defined in a real Hilbert space and has L-Lipschitz and pseudomonotone condition.Two new algorithms adopt inertial technology and non-monotonic step size rule,and their convergence can still be proved when the value of L is not given in advance.Finally,some numerical results are designed to demonstrate the computational efficiency of our two new algorithms. 展开更多
关键词 variational inequality inertial method non-monotonic step size rule Lipschitz continuity pseudomonotone mapping
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A Study of Triangle Inequality Violations in Social Network Clustering
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作者 Sanjit Kumar Saha Tapashi Gosswami 《Journal of Computer and Communications》 2024年第1期67-76,共10页
Clustering a social network is a process of grouping social actors into clusters where intra-cluster similarities among actors are higher than inter-cluster similarities. Clustering approaches, i.e. , k-medoids or hie... Clustering a social network is a process of grouping social actors into clusters where intra-cluster similarities among actors are higher than inter-cluster similarities. Clustering approaches, i.e. , k-medoids or hierarchical, use the distance function to measure the dissimilarities among actors. These distance functions need to fulfill various properties, including the triangle inequality (TI). However, in some cases, the triangle inequality might be violated, impacting the quality of the resulting clusters. With experiments, this paper explains how TI violates while performing traditional clustering techniques: k-medoids, hierarchical, DENGRAPH, and spectral clustering on social networks and how the violation of TI affects the quality of the resulting clusters. 展开更多
关键词 CLUSTERING Triangle inequality Violations Traditional Clustering Graph Clustering
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AGGREGATE SPECIAL FUNCTIONS TO APPROXIMATE PERMUTING TRI-HOMOMORPHISMS AND PERMUTING TRI-DERIVATIONS ASSOCIATED WITH A TRI-ADDITIVEψ-FUNCTIONAL INEQUALITY IN BANACH ALGEBRAS
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作者 Safoura Rezaei ADERYANI Azam AHADI +1 位作者 Reza SAADATI Hari M.SRIVASTAVA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期311-338,共28页
In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better... In this paper,we define a new class of control functions through aggregate special functions.These class of control functions help us to stabilize and approximate a tri-additiveψ-functional inequality to get a better estimation for permuting tri-homomorphisms and permuting tri-derivations in unital C*-algebras and Banach algebras by the vector-valued alternative fixed point theorem. 展开更多
关键词 permuting tri-homomorphism in Banach algebra permuting tri-derivation on C*-algebra fixed point theorem Ulam-Hyers-Rassias stability aggregate special functions tri-additiveψ-functional inequality
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基于LMI和扰动观测器的电动伺服系统RBF神经网络控制
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作者 李晓飞 范元勋 许鹿辉 《机械制造与自动化》 2024年第1期113-117,共5页
为了提高电动伺服系统的加载力跟踪精度,基于线性矩阵不等式(LMI)设计扰动观测器和控制器。针对系统中的非线性因素,采用RBF神经网络逼近系统的数学模型;在建立系统跟踪目标模型的基础上,根据LMI设计扰动观测器对控制器进行多余力的补偿... 为了提高电动伺服系统的加载力跟踪精度,基于线性矩阵不等式(LMI)设计扰动观测器和控制器。针对系统中的非线性因素,采用RBF神经网络逼近系统的数学模型;在建立系统跟踪目标模型的基础上,根据LMI设计扰动观测器对控制器进行多余力的补偿,利用李雅普诺夫函数证明扰动观测器和控制器的收敛;在MATLAB/Simulink中搭建仿真模型,分析扰动观测器和RBF神经网络在不同工况下对系统相应量的精准估计,且误差均满足所设定的性能指标,同时与PID控制相比较,证明所提控制策略的控制性能更优。 展开更多
关键词 电动伺服系统 线性矩阵不等式 扰动观测器 RBF神经网络
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基于LMI的框架结构分数阶控制方法研究
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作者 杨柳 周星德 +1 位作者 石贤增 金波 《计算力学学报》 CAS CSCD 北大核心 2023年第3期479-483,共5页
以框架结构为研究对象,采用分数阶状态方程进行控制器设计,提出了基于LMI的分数阶控制器设计方法.首先,把原系统振动方程改为阶次为1~2的分数阶状态方程,同时,构造同阶次分数阶控制器状态方程,进而组装为一个整体状态方程;其次,根据分... 以框架结构为研究对象,采用分数阶状态方程进行控制器设计,提出了基于LMI的分数阶控制器设计方法.首先,把原系统振动方程改为阶次为1~2的分数阶状态方程,同时,构造同阶次分数阶控制器状态方程,进而组装为一个整体状态方程;其次,根据分数阶系统稳定性条件确定满足系统渐进稳定性的不等式.为了获得可行解,在不等式中附加了两个参数,同时,令控制器参数矩阵为对称;再次,从仿真结果来看,控制效果过好,但控制力偏大,为此,控制力计算时附加了调节因子,以期在满足控制效果的基础上,降低所需控制力;最后给出了一个算例说明本文方法的可行性. 展开更多
关键词 框架结构 分数阶 lmi 附加参数 调节因子
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基于LMI的ROV执行器故障艏向容错控制
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作者 唐军 谢彬 +1 位作者 陈善颖 钱明炎 《国外电子测量技术》 北大核心 2023年第12期39-48,共10页
针对无人潜水器(remotely operated vehicle,ROV)的执行器故障问题,提出了一种基于线性矩阵不等式(linear matrix inequality,LMI)的鲁棒控制补偿修复方法。首先,建立了ROV 4自由度动力学模型,并对艏向模型进行线性化;利用自适应故障估... 针对无人潜水器(remotely operated vehicle,ROV)的执行器故障问题,提出了一种基于线性矩阵不等式(linear matrix inequality,LMI)的鲁棒控制补偿修复方法。首先,建立了ROV 4自由度动力学模型,并对艏向模型进行线性化;利用自适应故障估计器对执行器故障大小进行估计,并对控制量进行实时补偿;基于反步法和鲁棒控制技术对其进行控制策略设计;最后,采用Lyapunov相关理论验证了控制系统的稳定性。仿真结果表明,当执行器控制输入效率损失30%时,经过补偿修复后超调量下降13.98%,稳定时间减少50%;当控制输入效率损失40%时,修复后的超调量下降6.65%,稳定时间减少22.86%;实验结果表明,控制方法可在发生故障后40 s内恢复稳定状态,偏航角稳态误差约为±2°。因此,所提出的故障补偿修复策略能够降低对艏向控制的影响程度,保障ROV的稳定控制,并为水下机器人容错控制提供了一种新思路。 展开更多
关键词 无人潜水器 故障补偿修复 线性矩阵不等式 模型线性化 自适应故障估计器
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基于LMI的分段线性系统共存吸引子转迁控制研究
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作者 李得洋 吴少培 +4 位作者 李国芳 丁旺才 丁杰 俞力洋 卫晓娟 《振动与冲击》 EI CSCD 北大核心 2023年第19期30-39,共10页
以一类两自由度含间隙分段线性系统为研究对象,利用线性矩阵不等式(linear matrix inequality,LMI)和线性反馈方法对系统共存的吸引子进行在预期目标轨道引导下的转迁控制。在状态平面上利用胞映射方法对系统随参数变化时的共存吸引子... 以一类两自由度含间隙分段线性系统为研究对象,利用线性矩阵不等式(linear matrix inequality,LMI)和线性反馈方法对系统共存的吸引子进行在预期目标轨道引导下的转迁控制。在状态平面上利用胞映射方法对系统随参数变化时的共存吸引子进行识别,并基于Poincaré映射和Lyapunov指数研究了系统共存吸引子的稳定性及转迁机理。基于LMI和Lyapunov理论,并利用系统的向量场信息和S-procedure,将系统施加线性反馈控制器后的稳定性和反馈增益矩阵的求解问题转化为LMI描述。利用数值方法验证了所应用的线性反馈控制器及其增益矩阵选取方法的可行性及正确性。 展开更多
关键词 分段线性系统 共存吸引子 线性矩阵不等式(lmi) 吸引子转迁控制
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基于LMI的不确定随机时滞系统输出反馈保性能控制 被引量:1
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作者 甄玉婕 王天成 《鲁东大学学报(自然科学版)》 2023年第2期146-152,共7页
针对一类范数有界的随机时滞系统,研究在一定性能指标下的保性能控制问题。本文为获得能够实现系统保性能控制的最优输出反馈控制器,采用Lyapunov稳定性理论与LMI技术相结合的方法,将保性能控制问题转化为LMIs约束下的可行解问题。提出... 针对一类范数有界的随机时滞系统,研究在一定性能指标下的保性能控制问题。本文为获得能够实现系统保性能控制的最优输出反馈控制器,采用Lyapunov稳定性理论与LMI技术相结合的方法,将保性能控制问题转化为LMIs约束下的可行解问题。提出的控制器设计方案能够实现系统是依概率全局渐近稳定的,同时满足对系统性能指标的要求。此外,通过数值算例说明所提出控制方案的可行性。 展开更多
关键词 线性矩阵不等式 保性能控制 随机时滞系统 输出反馈
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基于风云四号卫星LMI数据的黑龙江省闪电活动特征研究
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作者 谢连妮 吴双 +1 位作者 韩书新 徐作敏 《自然灾害学报》 CSCD 北大核心 2023年第3期160-168,共9页
FY-4A闪电成像仪(LMI)为亚太地区首次研制发射的同类载荷,可以实现对闪电活动的实时、连续监测和跟踪。利用2018—2021年6—9月LMI的闪电事件(Event)观测数据,分析了黑龙江省闪电密度和辐亮度变化特征,结果表明:黑龙江省闪电密度和平均... FY-4A闪电成像仪(LMI)为亚太地区首次研制发射的同类载荷,可以实现对闪电活动的实时、连续监测和跟踪。利用2018—2021年6—9月LMI的闪电事件(Event)观测数据,分析了黑龙江省闪电密度和辐亮度变化特征,结果表明:黑龙江省闪电密度和平均辐亮度空间分布不均匀,闪电密度高值区主要分布在黑龙江省北部、中南部和西部;平均辐亮度高值区主要分布在黑龙江省北部、中部和东南部部分地区。黑龙江省东部和西部地区闪电密度和辐亮度呈反相关,西部闪电密度高但辐亮度较低,东部闪电密度低但辐亮度较高。闪电次数高发月份是6—7月,约占闪电事件总数的78.6%,闪电次数日变化呈现“双峰”,凌晨3时和傍晚16时为峰值时刻。闪电平均辐亮度随月份呈线性降低,且辐亮度月分布呈右偏态,日变化呈现“单峰”,峰值为中午12时左右。2018—2021年闪电事件辐亮度分布为偏态单峰型,0~20μJ/m^(2)/ster范围是高频率区间。 展开更多
关键词 黑龙江省 FY-4A lmi 辐亮度 闪电密度 分布特征
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Verification of the Landau Equation and Hardy’s Inequality
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作者 Salih Yousuf Mohamed Salih 《Applied Mathematics》 2023年第3期208-229,共22页
We prove the L estimate for the isotropic version of the homogeneous landau problem, which was explored by M. Gualdani and N. Guillen. As shown in a region of the smooth potentials range under values of the interactio... We prove the L estimate for the isotropic version of the homogeneous landau problem, which was explored by M. Gualdani and N. Guillen. As shown in a region of the smooth potentials range under values of the interaction exponent (2), a weighted Poincaré inequality is a natural consequence of the traditional weighted Hardy inequality, which in turn implies that the norms of solutions propagate in the L1 space. Now, the L estimate is based on the work of De Giorgi, Nash, and Moser, as well as a few weighted Sobolev inequalities. 展开更多
关键词 Hardy’s inequality Sobolev Inequalities the Landau Equation L-Estimate
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NOTES ON THE LOG-BRUNN-MINKOWSKI INEQUALITY
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作者 杨云龙 江楠 张德燕 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2333-2346,共14页
Böröczky-Lutwak-Yang-Zhang proved the log-Brunn-Minkowski inequality for two origin-symmetric convex bodies in the plane in a way that is stronger than for the classical Brunn-Minkowski inequality.In this pa... Böröczky-Lutwak-Yang-Zhang proved the log-Brunn-Minkowski inequality for two origin-symmetric convex bodies in the plane in a way that is stronger than for the classical Brunn-Minkowski inequality.In this paper,we investigate the relative positive center set of planar convex bodies.As an application of the relative positive center,we prove the log-Minkowski inequality and the log-Brunn-Minkowski inequality. 展开更多
关键词 cone-volume measure dilation position log-Brunn-Minkowski's inequality log-Minkowski's inequality relative positive center
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The Bell Inequality, Inviolable by Data Used Consistently with Its Derivation, Is Satisfied by Quantum Correlations Whose Probabilities Satisfy the Wigner Inequality
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作者 Louis Sica 《Journal of Modern Physics》 CAS 2023年第6期802-817,共16页
It is not generally known that the inequality that Bell derived using three random variables must be identically satisfied by any three corresponding data sets of ±1’s that are writable on paper. This surprising... It is not generally known that the inequality that Bell derived using three random variables must be identically satisfied by any three corresponding data sets of ±1’s that are writable on paper. This surprising fact is not immediately obvious from Bell’s inequality derivation based on causal random variables, but follows immediately if the same mathematical operations are applied to finite data sets. For laboratory data, the inequality is identically satisfied as a fact of pure algebra, and its satisfaction is independent of whether the processes generating the data are local, non-local, deterministic, random, or nonsensical. It follows that if predicted correlations violate the inequality, they represent no three cross-correlated data sets that can exist, or can be generated from valid probability models. Reported data that violate the inequality consist of probabilistically independent data-pairs and are thus inconsistent with inequality derivation. In the case of random variables as Bell assumed, the correlations in the inequality may be expressed in terms of the probabilities that give rise to them. A new inequality is then produced: The Wigner inequality, that must be satisfied by quantum mechanical probabilities in the case of Bell experiments. If that were not the case, predicted quantum probabilities and correlations would be inconsistent with basic algebra. 展开更多
关键词 Bell inequality Bell Theorem Wigner inequality Entanglement LOCALITY REALISM
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Some Refinement of Holder’s and Its Reverse Inequality
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作者 Musa O. Tijani Adefisayo Ojo Oludotun Akinsola 《Advances in Pure Mathematics》 2023年第9期597-609,共13页
Holder’s inequality, its refinement, and reverse have received considerable attention in the theory of mathematical analysis and differential equations. In this paper, we give some refinements of Holder’s inequality... Holder’s inequality, its refinement, and reverse have received considerable attention in the theory of mathematical analysis and differential equations. In this paper, we give some refinements of Holder’s inequality and its reverse using a simple analytical technique of algebra and calculus. Our results show many results related to holder’s inequality as special cases of the inequalities presented. 展开更多
关键词 Young’s inequality Kittaneh-Manasrah’s inequality Integrable Function Holder’s Cauchy-Schwarz inequality
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TRANSPORTATION COST-INFORMATION INEQUALITY FOR A STOCHASTIC HEAT EQUATION DRIVEN BY FRACTIONAL-COLORED NOISE
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作者 李瑞因 王新宇 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2519-2532,共14页
In this paper,we prove Talagrand’s T2 transportation cost-information inequality for the law of stochastic heat equation driven by Gaussian noise,which is fractional for a time variable with the Hurst index H∈(1/2,1... In this paper,we prove Talagrand’s T2 transportation cost-information inequality for the law of stochastic heat equation driven by Gaussian noise,which is fractional for a time variable with the Hurst index H∈(1/2,1),and is correlated for the spatial variable.The Girsanov theorem for fractional-colored Gaussian noise plays an important role in the proof. 展开更多
关键词 stochastic heat equation transportation cost-information inequality fractionalcolored noise
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THE FEKETE-SZEG?INEQUALITY AND SUCCESSIVE COEFFICIENTS DIFFERENCE FOR A SUBCLASS OF CLOSE-TO-STARLIKE MAPPINGS IN COMPLEX BANACH SPACES
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作者 徐庆华 方炜康 +1 位作者 冯伟珩 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期2075-2088,共14页
Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 fo... Let C be the familiar class of normalized close-to-convex functions in the unit disk.In[17],Koepf demonstrated that,as to a function■in the class C,■By applying this inequality,it can be proven that‖a3|-|a2‖≤1 for close-to-convex functions.Now we generalized the above conclusions to a subclass of close-to-starlike mappings defined on the unit ball of a complex Banach space. 展开更多
关键词 Fekete and Szego inequality successive coefficients difference bound close-to-starlike mappings complex Banach space
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Structural Gender Inequality and Mental Health among Chinese Men and Women
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作者 Lei Yang Zhipeng Sun 《International Journal of Mental Health Promotion》 2023年第1期31-43,共13页
Little is known about the association between structural gender inequality and health in patriarchal China.This study employed a sample from the Chinese Women’s Social Status,consisting of 26,139 participants aged 18... Little is known about the association between structural gender inequality and health in patriarchal China.This study employed a sample from the Chinese Women’s Social Status,consisting of 26,139 participants aged 18 and 70 years(13,494 women and 12,645 men).Structural gender inequality was assessed at the macro-,meso-,and micro-levels.Mental health was measured by the summed scores of eight questions on depressive symptoms.Multilevel linear regression was applied for analysis.Results showed that total sex ratio at birth was associated with poorer mental health among women and men but sex ratio at birth of the second-born child predicted better mental health.Gender inequality at meso-level resulted in poorer mental health and gender inequality at micro-level was associated with poorer mental health both for men and women.Eliminating structural gender inequality promotes populations’mental health in China. 展开更多
关键词 Structural gender inequality PATRIARCHY mental health men and women social determinants
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Inertial Subgradient Extragradient Algorithm for Solving Variational Inequality Problems with Pseudomonotonicity
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作者 Yuwan Ding Hongwei Liu Xiaojun Ma 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第5期65-75,共11页
In order to solve variational inequality problems of pseudomonotonicity and Lipschitz continuity in Hilbert spaces, an inertial subgradient extragradient algorithm is proposed by virtue of non-monotone stepsizes. More... In order to solve variational inequality problems of pseudomonotonicity and Lipschitz continuity in Hilbert spaces, an inertial subgradient extragradient algorithm is proposed by virtue of non-monotone stepsizes. Moreover, weak convergence and R-linear convergence analyses of the algorithm are constructed under appropriate assumptions. Finally, the efficiency of the proposed algorithm is demonstrated through numerical implementations. 展开更多
关键词 variational inequality extragradient method PSEUDOMONOTONICITY Lipschitz continuity weak and linear convergence
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基于LMI滑模变结构的倒立摆系统稳定控制
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作者 李梦婕 张永立 +1 位作者 崔世钢 索美霞 《天津职业技术师范大学学报》 2023年第1期38-43,49,共7页
以一级倒立摆为研究对象,利用牛顿法建立数学模型,针对其不确定性和稳定性问题,采用指数趋近律,利用线性矩阵不等式方法(LMI)辅助滑模控制策略推导设计出滑模变结构控制器,并结合最优控制理论和饱和函数优化系统参数,提高控制性能。通过... 以一级倒立摆为研究对象,利用牛顿法建立数学模型,针对其不确定性和稳定性问题,采用指数趋近律,利用线性矩阵不等式方法(LMI)辅助滑模控制策略推导设计出滑模变结构控制器,并结合最优控制理论和饱和函数优化系统参数,提高控制性能。通过Matlab对一级倒立摆系统进行性能仿真验证。仿真结果表明:优化改进后的滑模变结构控制方法在克服系统自身参数的不确定性和外界干扰的同时,有效地抑制了系统抖振,且系统响应快、超调小。 展开更多
关键词 倒立摆 滑模控制 线性矩阵不等式 李雅普诺夫 趋近律 稳定性
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