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Correlation Degree and Correlation Coefficient of Multi-Output Functions 被引量:1
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作者 JUGui-zhi ZHAOYa-qun 《Wuhan University Journal of Natural Sciences》 EI CAS 2005年第1期195-198,共4页
We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlati... We present definitions of the correlation degree and correlation coefficient of multi-output functions. Two relationships about the correlation degree of multi-output functions are proved. One is between the correlation degree and independency, the other is between the correlation degree and balance. Especially the paper discusses the correlation degree of affine multioutput functions. We demonstrate properties of the correlation coefficient of multi-output functions. One is the value range of the correlation coefficient, one is the relationship between the correlation coefficient and independency, and another is the sufficient and necessary condition that two multi-output functions are equivalent to each other. 展开更多
关键词 Key words multi output functions independency correlation degree BALANCE correlation coefficient
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Walsh Spectral Characteristics and the Auto-Correlation Function Characteristics of Forming Orthomorphic Permutations of Multi-Output Functions 被引量:4
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作者 ZHAO Yaqun WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1895-1898,共4页
Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalize... Orthomorphic permutations have good characteristics in cryptosystems. In this paper, by using of knowledge about relation between orthomorphic permutations and multi-output functions, and conceptions of the generalized Walsh spectrum of multi-output functions and the auto-correlation function of multi-output functions to investigate the Walsh spectral characteristics and the auto-correlation function characteristics of orthormophic permutations, several results are obtained. 展开更多
关键词 orthomorphic permutation multi-output functions walsh spectral auto-correlation function
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Dynamics Analysis of Active Variable Stiffness Vibration Isolator for Whole-Spacecraft Systems Based on Nonlinear Output Frequency Response Functions 被引量:3
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作者 Kefan Xu Yewei Zhang +2 位作者 Yunpeng Zhu Jian Zang Liqun Chen 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2020年第6期731-743,共13页
In order to improve the harsh dynamic environment experienced by heavy rockets during different external excitations,this study presents a novel active variable stiffness vibration isolator(AVS-VI)used as the vibratio... In order to improve the harsh dynamic environment experienced by heavy rockets during different external excitations,this study presents a novel active variable stiffness vibration isolator(AVS-VI)used as the vibration isolation device to reduce excessive vibration of the whole-spacecraft isolation system.The AVS-VI is composed of horizontal stiffness spring,positive stiffness spring,parallelogram linkage mechanism,piezoelectric actuator,acceleration sensor,viscoelastic damping,and PID active controller.Based on the AVS-VI,the generalized vibration transmissibility determined by the nonlinear output frequency response functions and the energy absorption rate is applied to analyze the isolation performance of the whole-spacecraft system with AVS-VI.The AVS-VI can conduct adaptive vibration suppression with variable stiffness to the whole-spacecraft system,and the analysis results indicate that the AVS-VI is efTective in reducing the extravagant vibration of the whole-spacecraft system,where the vibration isolation is decreased up to above 65%under different acceleration excitations.Finally,different parameters of AVS-VI are considered to optimize the whole-spacecraft system based on the generalized vibration transmissibility and the energy absorption rate. 展开更多
关键词 Vibration isolation Active variable stiffness vibration isolator Nonlinear output frequency response functions(NOFRFs) TRANSMISSIBILITY
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Relationship between Multi-Output Partially Bent Functions and Multi-Output Bent Functions 被引量:2
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作者 ZHAO Yaqun JU Guizhi WANG Jue 《Wuhan University Journal of Natural Sciences》 CAS 2006年第6期1887-1890,共4页
In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent function... In this paper, the definition of multl-output partially Bent functions is presented and some properties are discussed. Then the relationship between multi-output partially Bent functions and multi-output Bent functions is given in Theorem 4, which includes Walsh spectrum expression and function expression. This shows that multi-output partially Bent functions and multi-output Bent functions can define each other in principle. So we obtain the general method to construct multi-output partially Bent functions from multi-output Bent functions. 展开更多
关键词 multi-output partially Bent functions multi-output Bent functions Walsh spectrum CONSTRUCTING
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Dynamic design of a nonlinear energy sink with NiTiNOL-steel wire ropes based on nonlinear output frequency response functions 被引量:7
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作者 Yewei ZHANG Kefan XU +3 位作者 Jian ZANG Zhiyu NI Yunpeng ZHU Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第12期1791-1804,共14页
A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is cou... A novel vibration isolation device called the nonlinear energy sink(NES)with NiTiNOL-steel wire ropes(NiTi-ST)is applied to a whole-spacecraft system.The NiTi-ST is used to describe the damping of the NES,which is coupled with the modified Bouc-Wen model of hysteresis.The NES with NiTi-ST vibration reduction principle uses the irreversibility of targeted energy transfer(TET)to concentrate the energy locally on the nonlinear oscillator,and then dissipates it through damping in the NES with NiTi-ST.The generalized vibration transmissibility,obtained by the root mean square treatment of the harmonic response of the nonlinear output frequency response functions(NOFRFs),is first used as the evaluation index to analyze the whole-spacecraft system in the future.An optimization analysis of the impact of system responses is performed using different parameters of NES with NiTi-ST based on the transmissibility of NOFRFs.Finally,the effects of vibration suppression by varying the parameters of NiTi-ST are analyzed from the perspective of energy absorption.The results indicate that NES with NiTi-ST can reduce excessive vibration of the whole-spacecraft system,without changing its natural frequency.Moreover,the NES with NiTi-ST can be directly used in practical engineering applications. 展开更多
关键词 NONLINEAR energy sink(NES) vibration isolation NiTiNOL-steel wire ROPE (NiTi-ST) NONLINEAR output frequency response function(NOFRF) ROOT mean square TRANSMISSIBILITY
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IMPROVEMENT OF THE ALGORITHM PRINCIPLES FOR MINIMIZATION OF MULTI-OUTPUT FUNCTIONS
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作者 陈苏 许道荣 《Journal of Electronics(China)》 1993年第2期116-123,共8页
In this paper,the application of extraction principle for logic function minimiza-tion to multi-output case is studied.A defect in original algorithm in dealing with multi-outputextrema is made up,and on this base,thr... In this paper,the application of extraction principle for logic function minimiza-tion to multi-output case is studied.A defect in original algorithm in dealing with multi-outputextrema is made up,and on this base,three kinds of less-than terms in different conditions aredefined.In addition,three kinds of generalized definition of less-than terms are given,so as to findout more efficiently the covers with minimal number of terms and irredundant function outputs.This work makes the multi-output extraction principle closer to perfection.An algorithm basedon the work is presented. 展开更多
关键词 MULTI-output function MINIMIZATION Reduction of PLA MINIMAL AND-OR expression
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An Analysis of the Relationship between Output Corpus and Language Output Function
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作者 罗珂 《海外英语》 2019年第4期93-94,共2页
The study is to verify the relationship between the output corpus and language output function and to test the three func-tions of pushed output. It attempts to give some implications for non-English major and English... The study is to verify the relationship between the output corpus and language output function and to test the three func-tions of pushed output. It attempts to give some implications for non-English major and English-learning. The results show that theoutput corpus is related to language output function. 展开更多
关键词 output CORPUS language output function pushed output TEACHER feedback students’discourse
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Tool Condition Monitoring Based on Nonlinear Output Frequency Response Functions and Multivariate Control Chart
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作者 Yufei Gui Ziqiang Lang +1 位作者 Zepeng Liu Hatim Laalej 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第4期243-251,共9页
Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significa... Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significant damage to workpieces and reduce manufacturing costs.Recently,an innovative TCM approach based on sensor data modelling and model frequency analysis has been proposed.Different from traditional signal feature-based monitoring,the data from sensors are utilized to build a dynamic process model.Then,the nonlinear output frequency response functions,a concept which extends the linear system frequency response function to the nonlinear case,over the frequency range of the tooth passing frequency of the machining process are extracted to reveal tool health conditions.In order to extend the novel sensor data modelling and model frequency analysis to unsupervised condition monitoring of cutting tools,in the present study,a multivariate control chart is proposed for TCM based on the frequency domain properties of machining processes derived from the innovative sensor data modelling and model frequency analysis.The feature dimension is reduced by principal component analysis first.Then the moving average strategy is exploited to generate monitoring variables and overcome the effects of noises.The milling experiments of titanium alloys are conducted to verify the effectiveness of the proposed approach in detecting excessive flank wear of solid carbide end mills.The results demonstrate the advantages of the new approach over conventional TCM techniques and its potential in industrial applications. 展开更多
关键词 intelligent manufacturing multivariate control chart Nonlinear Autoregressive with eXogenous Input modelling Nonlinear output Frequency Response functions tool condition monitoring
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Spectral Characteristics of the Best Affine Approach of Multi-Output m-Valued Logical Functions
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作者 ZHAO Yaqun YING Dinghai FENG Dengguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第1期185-188,共4页
This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine func... This paper discusses the best affine approach (BAA) of multi-output m-valued logical functions. First, it gives the spectra of rate of accordance between multi-output m-valued logical functions and their affine functions, then analyzes the BAA of multi-output m-valued logical functions and finally gives the spectral characteristics of BAA of multi-output m-valued logical functions. 展开更多
关键词 multi-output m-valued logical functions linear spectrum cyclic spectrum BAA(best affine approach)
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具有时滞与状态约束的一类非线性系统自适应跟踪控制
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作者 范永青 李培龙 《西安邮电大学学报》 2026年第1期128-136,共9页
针对具有输入时滞和状态约束的一类非线性自适应系统,提出一种基于障碍Lyapunov函数与模糊切换控制的自适应跟踪控制方法。该方法利用Pade近似对输入时滞进行补偿,引入平滑切换函数构造连续控制律,确保系统状态始终满足预设约束条件。同... 针对具有输入时滞和状态约束的一类非线性自适应系统,提出一种基于障碍Lyapunov函数与模糊切换控制的自适应跟踪控制方法。该方法利用Pade近似对输入时滞进行补偿,引入平滑切换函数构造连续控制律,确保系统状态始终满足预设约束条件。同时,设计基于状态误差的模糊逻辑控制器,通过模糊规则提高控制精度,并增强系统的鲁棒性。为降低计算复杂度,采用参数自适应律对隶属函数向量的范数进行在线更新,有效简化了模糊系统的设计。所提控制方案无需先验系统模型信息,可适应多种复杂非线性动态特性。仿真实验以倒立摆系统为例,在不同输入时滞条件下验证了该方法的有效性,结果表明该控制器具有良好的跟踪性能、稳定性和约束保持能力。 展开更多
关键词 模糊控制 非线性控制系统 输入延迟 输出约束 反推设计技术 切换函数
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农机投入结构优化对农业产出的影响机制——基于东北三省粮食种植户的实证分析
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作者 徐霞 耿献辉 +1 位作者 吕杰 尹冠球 《中国农业大学学报》 北大核心 2026年第3期320-333,共14页
针对农业劳动力成本攀升与土地资源约束趋紧的现实问题,基于2023年我国东北三省1526户粮食种植户调查数据,构建“农机投入结构—要素重组—农业产出”的理论框架,采用连续型农机投入结构指数(农机外包服务投入占比)嵌入超越对数生产函数... 针对农业劳动力成本攀升与土地资源约束趋紧的现实问题,基于2023年我国东北三省1526户粮食种植户调查数据,构建“农机投入结构—要素重组—农业产出”的理论框架,采用连续型农机投入结构指数(农机外包服务投入占比)嵌入超越对数生产函数,并引入三阶交互项,实证分析农机投入结构对农业产出的影响及其机制。结果表明:1)农机投入结构显著促进粮食产量提升,主要采用土地扩张与劳动力替代效应实现;2)高质量农机外包服务及联合购买模式显著增强了农机投入结构的增产作用;3)异质性分析表明,农机投入结构对小规模农户和兼业农户的粮食产量促进效果更为显著。基于研究结果提出如下政策建议:推动农机补贴从购置补贴向应用补贴转型,提升农机外包服务质量,推广联合购买模式,并加强对小规模及兼业农户的支持,为服务规模经营与土地规模经营的协同推进提供实践路径。 展开更多
关键词 农机投入结构 超越对数生产函数 要素配置 粮食产量
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约束非线性系统的固定时间滤波反步控制
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作者 李爽 周超 王芳 《控制理论与应用》 北大核心 2026年第2期406-414,共9页
针对一类带有输出误差约束和外界干扰的非线性系统,结合固定时间干扰观测器,本文设计滤波反步控制策略.首先,设计预定性能函数,处理输出误差约束问题.其次,利用固定时间滤波器和固定时间干扰观测器,分别解决反步控制的“计算爆炸”问题... 针对一类带有输出误差约束和外界干扰的非线性系统,结合固定时间干扰观测器,本文设计滤波反步控制策略.首先,设计预定性能函数,处理输出误差约束问题.其次,利用固定时间滤波器和固定时间干扰观测器,分别解决反步控制的“计算爆炸”问题和外界干扰问题,干扰估计误差在固定时间内收敛到零.再次,采用Lyapunov理论分析闭环系统是固定时间稳定的,且输出误差在预设时间内满足约束要求.最后,通过比仿真验证控制策略的有效性. 展开更多
关键词 非线性系统 输出误差约束 预定性能函数 固定时间干扰观测器 固定时间控制 滤波器
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基于高阶障碍李雅普诺夫函数的约束非线性系统的预定跟踪精度控制
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作者 练桂铭 乔瑜姣 +1 位作者 李明 黄宇导 《现代信息科技》 2026年第6期131-135,共5页
针对一类不确定非线性系统,文章研究了自适应预定跟踪精度控制问题。该研究构造了一种新的障碍函数,在存在未知参数和外界干扰的情况下,通过控制参数与自适应参数的调整,使输出跟踪误差保持在任意小区域内,并扩大了系统输出初始值的取... 针对一类不确定非线性系统,文章研究了自适应预定跟踪精度控制问题。该研究构造了一种新的障碍函数,在存在未知参数和外界干扰的情况下,通过控制参数与自适应参数的调整,使输出跟踪误差保持在任意小区域内,并扩大了系统输出初始值的取值范围。在此基础上,结合障碍函数与反步法,设计了一种自适应跟踪控制方法,该方法能够避免输出约束被违反并保证跟踪误差收敛至预设紧集。仿真结果验证了方法的有效性。 展开更多
关键词 非线性系统 障碍李雅普诺夫函数 预定跟踪精度 输出约束 光滑函数
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基于高阶滤波超螺旋ESO的单电感双输出Buck变换器滑模自抗扰控制
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作者 李聪林 皇金锋 +1 位作者 章乾 陈旭 《上海交通大学学报》 北大核心 2026年第1期87-99,I0004,共14页
单电感双输出(SIDO)Buck变换器在受到负载扰动时,支路间存在严重交叉耦合影响,输出信号易受到高频测量噪声等不确定因素影响.针对上述问题,提出一种基于高阶滤波超螺旋扩张状态观测器(ESO)的滑模自抗扰控制策略.首先,根据SIDO Buck变换... 单电感双输出(SIDO)Buck变换器在受到负载扰动时,支路间存在严重交叉耦合影响,输出信号易受到高频测量噪声等不确定因素影响.针对上述问题,提出一种基于高阶滤波超螺旋扩张状态观测器(ESO)的滑模自抗扰控制策略.首先,根据SIDO Buck变换器的数学模型,将内部参数影响和外部扰动等不确定因素分离为集总扰动,建立不考虑物理参数的自抗扰模型;其次,设计一种高阶滤波超螺旋扩张状态观测器,更精准地估计补偿集总扰动,提高抑制噪声和交叉影响的能力,并根据有限时间稳定性理论证明其稳定性;再次,设计改进的超螺旋滑模反馈控制律,保证滑动模态阶段和到达阶段能快速收敛,同时更好地抑制抖振,并选取李雅普诺夫函数对反馈控制律进行稳定性分析;最后,利用仿真和实验对比验证了所提控制策略能有效减小交叉影响、抑制噪声、提高系统的暂态性能. 展开更多
关键词 扩张状态观测器 自抗扰控制 单电感双输出Buck变换器 李雅普诺夫函数
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基于观测器的状态约束Hamilton系统的输出调节
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作者 周粤 徐松 《宁波大学学报(理工版)》 2026年第2期113-120,共8页
针对具有状态约束的Hamilton系统的鲁棒输出调节问题,提出了一种基于观测器的输出调节方法。利用内模原理和障碍存储函数(BSF)方法,给出了系统BSF存在的充分条件,所得到的调节器在保证闭环系统满足状态约束条件的同时,解决系统输出调节... 针对具有状态约束的Hamilton系统的鲁棒输出调节问题,提出了一种基于观测器的输出调节方法。利用内模原理和障碍存储函数(BSF)方法,给出了系统BSF存在的充分条件,所得到的调节器在保证闭环系统满足状态约束条件的同时,解决系统输出调节问题。该方法能保持Hamilton系统耗散结构,将系统鲁棒输出调节问题转化为镇定问题,从而避免求解调节器方程和Hamilton-Jacobi-Issacs不等式。数值仿真结果表明该方法具有有效性。 展开更多
关键词 状态约束 HAMILTON系统 输出调节 障碍存储函数
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ON THE DEGREE OF COMPLETENESS OF CRYPTOGRAPHIC FUNCTIONS 被引量:1
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作者 Liu Jian Chen Lusheng 《Journal of Electronics(China)》 2014年第5期489-495,共7页
This paper discusses the degree of completeness of cryptographic functions, which is one of the cryptographic criteria should be considered in the design of stream ciphers. We establish the relationships between the d... This paper discusses the degree of completeness of cryptographic functions, which is one of the cryptographic criteria should be considered in the design of stream ciphers. We establish the relationships between the degree of completeness and other cryptographic criteria. For resilient Boolean functions, a method to enhance the degree of completeness is proposed, while the nonlinearity and the algebraic degree do not decrease. Moreover, two constructions of resilient functions are provided, which have optimal degree of completeness, high nonlinearity, and high algebraic degree. 展开更多
关键词 Degree of completeness Multi-output Boolean functions NONLINEARITY Resiliency Linear structures
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基于Output Control函数生成缓存文件为php页面提速
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作者 陈海虹 《电脑知识与技术(过刊)》 2009年第4X期4444-4445,4466,共3页
根据PHP Out Control函数的特点,为PHP输出的内容和函数调用结果生成缓存文件,提高了PHP执行的速度。介绍了利用Output Control函数生成缓存文件的设计思想及实现过程,并对其中采用的相关技术进行了探讨。
关键词 PHP output Control函数 缓存文件
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Extended ambiguity function for bistatic MIMO radar 被引量:2
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作者 Haowen Chen Yiping Chen +1 位作者 Zhaocheng Yang Xiang Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第2期195-200,共6页
This paper derives the extended ambiguity function for a bistatic multiple-input multiple-output (MIMO) radar system, which includes the whole radar system parameters: geometric sensor configuration, waveforms, ran... This paper derives the extended ambiguity function for a bistatic multiple-input multiple-output (MIMO) radar system, which includes the whole radar system parameters: geometric sensor configuration, waveforms, range, range rate, target scattering and noise characteristics. Recent research indicates the potential pa- rameter estimate performance of bistatic MIMO radars. And this ambiguity function can be used to analyze the parameter estimate performance for the relationship with the Cramer-Rao bounds of the estimated parameters. Finally, some examples are given to demonstrate the good parameter estimate performance of the bistatic MIMO radar, using the quasi-orthogonal waveforms based on Lorenz chaotic systems. 展开更多
关键词 bistatic multiple-input multiple-output (MIMO) radar ambiguity function parameter estimate Cramer-Rao bound (CRB) quasi-orthogonal waveforms.
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Stabilization of a class of discrete-time switched systems via observer-based output feedback 被引量:1
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作者 Jiao LI Yuzhong LIU 《控制理论与应用(英文版)》 EI 2007年第3期307-311,共5页
In this paper, observer-based static output feedback control problem for discrete-time uncertain switched systems is investigated under an arbitrary switching rule. The main method used in this note is combining switc... In this paper, observer-based static output feedback control problem for discrete-time uncertain switched systems is investigated under an arbitrary switching rule. The main method used in this note is combining switched Lyapunov function (SLF) method with Finsler's Lemma. Based on linear matrix inequality (LMI) a less conservative stability condition is established and this condition allows extra degree of freedom for stability analysis. Finally, a simulation example is given to illustrate the efficiency of the result. 展开更多
关键词 Discrete-time switched systems STABILIZATION UNCERTAINTY output feedback Switched Lyapunov function (SLF) Linear matrix inequality (LMI)
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Function Observer Based Event-triggered Control for Linear Systems with Guaranteed L_∞-Gain
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作者 Pei Jia Fei Hao Hao Yu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2015年第4期394-402,共9页
This paper is devoted to event-triggered control design for linear systems based on function observer. More specifically, the main purpose is to design event-triggered mechanisms that trigger transmissions when the di... This paper is devoted to event-triggered control design for linear systems based on function observer. More specifically, the main purpose is to design event-triggered mechanisms that trigger transmissions when the difference between the current value of the system and its previously transmitted value which includes the plant output or the function observer output exceeds an additional threshold. For such an eventtriggered mechanism, we derive conditions in terms of matrix inequality to guarantee the stability as well as longer inter-event time. We propose two approaches to investigate the closed-loop model, namely, reformulating the event-triggered control system as a hybrid system and interpreting the event-induced error as exogenous disturbance. Furthermore, the minimum inter-event time is guaranteed to be strictly positive. An example is presented to illustrate the feasibility and efficiency of the theoretic results. © 2014 Chinese Association of Automation. 展开更多
关键词 Dynamical systems Hybrid systems
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