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石蜡切片温度调控对组织切片厚度及HE染色质量影响的研究
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作者 于澍泽 宋晓艳 +2 位作者 徐心怡 王雯婷 许海敏 《现代生物医学进展》 2026年第1期22-29,共8页
目的:评估不同温度管理方式对石蜡切片厚度及苏木素-伊红(H&E)染色质量的影响,探讨石蜡切片温度管理在病理实验操作中的意义。方法:选取消化系统石蜡包埋人体病理组织块,分为预冷后常温切片组(常温组)和预冷后冰盒降温切片(低温组)... 目的:评估不同温度管理方式对石蜡切片厚度及苏木素-伊红(H&E)染色质量的影响,探讨石蜡切片温度管理在病理实验操作中的意义。方法:选取消化系统石蜡包埋人体病理组织块,分为预冷后常温切片组(常温组)和预冷后冰盒降温切片(低温组)进行连续切片。比较两组在表面温度变化、厚度、染色阳性比方面的差异。结果:常温组石蜡块表面温度随切片时间持续上升,低温组温度呈波动式变化,整体维持在8-11℃。常温组切片平均厚度和染色阳性百分比显著高于低温组(P<0.001),常温组厚度与染色结果分布宽散且存在长尾,低温组分布集中,呈单峰形态。线性回归分析表明切片厚度与染色阳性百分比呈显著正相关(R^(2)=0.6069,P<0.0001),厚度增加导致阳性面积系统性升高。结论:石蜡切片温度管理是影响石蜡切片质量的关键因素,采用冰盒降温能够提高厚度均一性并改善苏木素-伊红(H&E)染色一致性,为常规病理实验室提供了一种简便、可行的质量控制手段。 展开更多
关键词 石蜡切片 质量控制 苏木素-伊红(h&E)制片 石蜡切片温度管理
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基于模糊滑模控制策略的H桥并联逆变电源系统研究
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作者 付宗杰 高格 汪舒生 《佳木斯大学学报(自然科学版)》 2026年第1期34-37,共4页
目前在全超导托卡马克核聚变实验装置(EAST)中,采用传统的比例-积分(PI)控制策略时,内真空室电源系统的输出电流会可能出现谐波、超调和稳定时间过慢等问题。为了应对谐波影响和提高快速准确跟踪能力,提出一种基于模糊切换增益的改进滑... 目前在全超导托卡马克核聚变实验装置(EAST)中,采用传统的比例-积分(PI)控制策略时,内真空室电源系统的输出电流会可能出现谐波、超调和稳定时间过慢等问题。为了应对谐波影响和提高快速准确跟踪能力,提出一种基于模糊切换增益的改进滑模控制策略。建立H桥并联逆变系统的数学模型,根据建立的系统模型设计出了滑模控制器;同时引入连续的双曲正切函数,并且采用了模糊控制切换增益方法,根据系统的误差来动态调整滑模控制器增益,不仅提高系统稳态精度,还减小了系统的抖振。仿真结果表明,相较于采用传统PI控制策略,模糊滑模控制策略具有更加优良的抑制谐波效果和电流跟踪特性。 展开更多
关键词 h桥并联逆变系统 滑模控制 模糊切换增益 谐波抑制
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时滞耦合神经网络的分散式H∞脉冲簇同步
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作者 王圆 陈武华 《广西大学学报(自然科学版)》 北大核心 2026年第1期188-202,共15页
为了研究具有传输时滞和外部干扰的时滞耦合神经网络的H∞簇同步问题,提出分散式时滞脉冲簇同步策略。借助增维技术,将时滞脉冲建模为切换脉冲。在此基础上发展切换加权时变Lyapunov泛函方法,该方法能充分利用增维模型的混杂结构信息以... 为了研究具有传输时滞和外部干扰的时滞耦合神经网络的H∞簇同步问题,提出分散式时滞脉冲簇同步策略。借助增维技术,将时滞脉冲建模为切换脉冲。在此基础上发展切换加权时变Lyapunov泛函方法,该方法能充分利用增维模型的混杂结构信息以及节点间的耦合关系。基于线性矩阵不等式,建立时滞耦合神经网络H∞簇同步准则,该准则能刻画脉冲驻留时间和脉冲时滞对簇同步性能的影响。数值算例进一步验证结果的有效性。研究结果表明:提出的分散式时滞脉冲簇同步方案允许同时考虑神经元内部时滞、不同节点之间的耦合时滞、外部干扰以及节点采样信息的传输时滞,与已有的脉冲簇同步方案相比,更具普适性。基于系统增维建模技术和加权时变Lyapunov泛函技术,提出簇同步误差系统稳定性和H∞簇同步性能分析的新方法,该方法能有效构建同步增益、脉冲驻留时间、脉冲时滞以及H∞簇同步性能之间的内在联系。 展开更多
关键词 h∞簇同步 时滞耦合神经网络 分散脉冲控制 时滞脉冲 切换时变Lyapunov泛函
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基于级联H桥的混合潮流控制器及控制策略研究 被引量:2
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作者 杨用春 杜翔宇 +3 位作者 李旭东 杨鹏 董增波 马源媛 《华北电力大学学报(自然科学版)》 北大核心 2025年第4期44-52,共9页
随着高比例新能源替代传统火电机组大规模接入电网,潮流动态控制能力大幅降低,区域电网输电通道潮流分布不均匀情况加剧,部分输电通道和断面潮流过重、N-1过负荷情况突出,电网中输电断面瓶颈和线路输电能力闲置的情况并存,严重影响了电... 随着高比例新能源替代传统火电机组大规模接入电网,潮流动态控制能力大幅降低,区域电网输电通道潮流分布不均匀情况加剧,部分输电通道和断面潮流过重、N-1过负荷情况突出,电网中输电断面瓶颈和线路输电能力闲置的情况并存,严重影响了电网整体输供电能力发挥和安全可靠性水平。论文针对新能源潮流外送通道受阻的应用场景,提出了一种基于级联H桥的混合潮流控制器(HPFC),结合了无源的移相变压器(PST)和有源的级联H桥型换流器的优点,通过对线路阻抗幅值和相角大范围柔性化连续调节,可以实现对潮流的精准快速的控制;其次理论分析了PST的潮流调控方法和级联H桥的工作原理确定了HPFC的工作方式和运行范围,再次针对HPFC中有源和无源部分调节区域、调节速度之间的差异提出一种协同控制策略,最后基于220 kV电网双回线路应用场景,在PSCAD/EMTDC环境中进行仿真分析,验证了所提出的基于级联H桥的混合潮流控制器控制策略的可行性。 展开更多
关键词 混合潮流控制器 移相变压器 级联h 潮流控制 分层控制
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H_∞ Consensus Control of Discrete-Time Multi-Agent Systems Under Network Imperfections and External Disturbance 被引量:13
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作者 Arezou Elahi Alireza Alfi Hamidreza Modares 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第3期667-675,共9页
This paper presents a distributed control protocol for consensus control of multi-agent systems(MASs) under external disturbances and network imperfections, including communication delay and random packet dropout. To ... This paper presents a distributed control protocol for consensus control of multi-agent systems(MASs) under external disturbances and network imperfections, including communication delay and random packet dropout. To comply with the discrete nature of networked systems, in contrast to most of the existing work for MASs under network imperfections,the agents are modeled by discrete-time dynamics. The communication network is considered to be undirected, its delay is considered to be time-varying but bounded, and its packet dropout is modeled by a Bernoulli distributed white sequence.Sufficient conditions in terms of linear matrix inequalities(LMIs)for asymptotic mean-square consensus stability are derived under network imperfections without considering external disturbances.A desired disturbance attenuation level in the presence of both external disturbances and network imperfections is also provided.A simulation example is given to verify the effectiveness of the proposed approach in coping with network imperfection and disturbances. 展开更多
关键词 CONSENSUS distributed control h control packet DROPOUT stability time delay
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H_∞ Control of Bio-dissimilation Process of Glycerol to 1,3-Propanediol 被引量:10
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作者 XU Gong-Xian SHAO Cheng XIU Zhi-Long 《自动化学报》 EI CSCD 北大核心 2006年第1期112-119,共8页
A robust controller is designed by using the bilinear transformation and H∞ mixed sensitivity method for bio-dissimilation process of glycerol to 1,3-propanediol. Under the controller the system works near an optimal... A robust controller is designed by using the bilinear transformation and H∞ mixed sensitivity method for bio-dissimilation process of glycerol to 1,3-propanediol. Under the controller the system works near an optimal steady-state for the volumetric productivity of 1,3-propanediol attaining its maximization. The design procedure is carried out by tuning the transformation parameter and DC gain of the performance weighted function, which is an iterative and optimal search process. Simulation results are presented which show that the designed robust controller not only ensures the robust stability of the system in face of the parametric variations in the model, but also makes the system have a favourable robust tracking performance. The validity of the proposed H∞ controller has been tested. 展开更多
关键词 h∞控制 混合灵敏度 双线性转换 生物过程控制 鲁棒控制
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Delay-dependent Robust H∞ Control for Uncertain Singular Systems with State Delay 被引量:22
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作者 FANG Mei 《自动化学报》 EI CSCD 北大核心 2009年第1期65-70,共6页
这份报纸讨论延期依赖者的问题为有州的延期的不明确的单个系统的柔韧的 H 控制。把途径基于线性矩阵不平等(LMI ) ,我们设计一个州的反馈控制器,它保证为所有可被考虑的无常,结果的靠近环的系统是常规的,推动与 H 免费、稳定的标... 这份报纸讨论延期依赖者的问题为有州的延期的不明确的单个系统的柔韧的 H 控制。把途径基于线性矩阵不平等(LMI ) ,我们设计一个州的反馈控制器,它保证为所有可被考虑的无常,结果的靠近环的系统是常规的,推动与 H 免费、稳定的标准界限限制。所有获得的结果是延期依赖者并且由不包含系统矩阵的分解的严格的 LMI 提出。数字例子证明建议方法不比存在的保守。 展开更多
关键词 奇数时间延误系统 延迟依赖 自动控制 线性平均直径
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Improved Hybrid Robust Control Method for the Electromechanical Actuator in Aircrafts 被引量:9
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作者 LU Hao LI Yunhu +1 位作者 TIAN Shengli NIE Zhenjin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期443-450,共8页
In the flight process of aircrafts, their electromechanical actuators(EMA) must have the ability of enduring uncertainties caused by factors such as load disturbance, the variation of work temperature and the EMA's... In the flight process of aircrafts, their electromechanical actuators(EMA) must have the ability of enduring uncertainties caused by factors such as load disturbance, the variation of work temperature and the EMA's nonlinearity. At present, in order to increase the EMA's robustness on the uncertainties, the H, control method has been applied in aircrafts. The major problems with standard H∞ control lie in the large overshoot of step response and the high orders of the controller. For the purpose of addressing the two problems, this paper investigates several kinds of robust control strategies of the EMA. A mathematical model of the EMA is first built, and then with MATLAB software a H∞ controller and an improved hybrid robust controller composed of a reduced order H∞controller and a lead compensator are designed. In order to make a scientific comparison of the control effects of H∞ controller, hybrid controller and classic proportion-integral-differential(PID) controller, a simulation research is made in respect of the open loop frequency response and the closed loop step response of the three controllers. For comparing the robustness of the three controllers, the load torque is entered as a disturbance and the disturbance response of error and control input are thus obtained. The experiments with the three controllers are also conducted. Through giving the EMA a command and a disturbance torque successively, the transient response and disturbing process of EMA are recorded. The simulation and experiment results show that with the help of the hybrid controller, the EMA not only guarantees good dynamic characteristics, but also has strong robustness of disturbance rejection. Therefore, the excogitated H∞ hybrid control method effectively solves the problem of large overshoot in dynamic response, and moderately meets the requirement of overcoming the uncertainties in the EMA of aircrafts. 展开更多
关键词 aircrafts electromechanical actuator h control hybrid robust control disturbance rejection
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Improved Results on Delay-dependent H∞ Control for Singular Time-delay Systems 被引量:14
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作者 WU Zheng-Guang SU Hong-Ye CHU Jian 《自动化学报》 EI CSCD 北大核心 2009年第8期1101-1106,共6页
关键词 时滞广义系统 控制方法 泛函系统 计算方法
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Adaptive H~∞ Control of Nonlinear Systems with Neural Networks 被引量:6
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作者 姜长生 陈谋 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2003年第1期36-41,共6页
The discussion is devoted to the adaptive H ∞ control method based on RBF neural networks for uncertain nonlinear systems in this paper. The controller consists of an equivalent controller and an H ∞ cont... The discussion is devoted to the adaptive H ∞ control method based on RBF neural networks for uncertain nonlinear systems in this paper. The controller consists of an equivalent controller and an H ∞ controller. The RBF neural networks are used to approximate the nonlinear functions and the approximation errors of the neural networks are used in the adaptive law to improve the performance of the systems. The H ∞ controller is designed for attenuating the influence of external disturbance and neural network approximation errors. The controller can not only guarantee stability of the nonlinear systems, but also attenuate the effect of the external disturbance and neural networks approximation errors to reach performance indexes. Finally, an example validates the effectiveness of this method. 展开更多
关键词 neural networks nonlinear systems adaptive control h control
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Quantized Dynamic Output Feedback H∞ Control for Discrete-time Systems with Quantizer Ranges Consideration 被引量:7
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作者 CHE Wei-Wei YANG Guang-Hong 《自动化学报》 EI CSCD 北大核心 2008年第6期652-658,共7页
使量子化的动态产量反馈 H 控制为的问题分离时间线性时间不变(LTI ) 系统在这份报纸被调查。考虑的 quantizer 动态、镇静一可调节激增参数和静态的 quantizer。静态的 quantizer 范围具有实际意义并且充分被考虑。首先,考虑量子化错... 使量子化的动态产量反馈 H 控制为的问题分离时间线性时间不变(LTI ) 系统在这份报纸被调查。考虑的 quantizer 动态、镇静一可调节激增参数和静态的 quantizer。静态的 quantizer 范围具有实际意义并且充分被考虑。首先,考虑量子化错误,使量子化的控制策略控制器状态依赖于不仅而且在系统测量产量上,它被建议以便使量子化的靠近环的系统是 asymptotically 稳定的,与规定 H,性能跳。根据这结果,然后,一个反复的基于 LMI 的优化算法被开发优化静态的 quantizer 范围为靠近环的系统满足 H 表演要求。一个例子被举说明建议方法的有效性。 展开更多
关键词 离散时间系统 量子学 动力系统 反馈控制系统
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Distributed H_∞ control of multi-agent systems with directed networks 被引量:6
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作者 刘伟 柳爱利 周绍磊 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期73-79,共7页
This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communica... This paper studies the distributed H∞control problem of identical linear time invariant multi-agent systems subject to external disturbances. A directed graph containing a spanning tree is used to model the communication topology. Based on the relative states of the neighbor agents and a subset of absolute states of the agents, distributed static H∞controllers are proposed. The concept of an H∞performance region is extended to the directed graph situation. Then the results are used to solve the leader–follower H∞consensus problem. Sufficient conditions are proposed based on bounded real lemma and algebraic graph theory. The effectiveness of the theoretical results is illustrated via numerical simulations. 展开更多
关键词 multi-agent systems h control performance region leader–follower h consensus
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Finite Horizon H∞ Preview Control 被引量:5
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作者 WANG Hong-Xia ZHANG Huan-Shui 《自动化学报》 EI CSCD 北大核心 2010年第2期327-331,共5页
关键词 h 控制 控制理论 系统工程 稳定性
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Robust and Non-fragile H_∞ Control for a Class of Uncertain Jump Linear Systems 被引量:6
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作者 KANG Yu XI Hong-Sheng ZHANG Da-Li JI Hai-Bo 《自动化学报》 EI CSCD 北大核心 2006年第3期438-443,共6页
This paper describes the synthesis of robust and non-fragile H∞ state feedback controllers for a class of uncertain jump linear systems with Markovian jumping parameters and state multiplicative noises. Under the ass... This paper describes the synthesis of robust and non-fragile H∞ state feedback controllers for a class of uncertain jump linear systems with Markovian jumping parameters and state multiplicative noises. Under the assumption of a complete access to the norm-bounds of the system uncertainties and controller gain variations, sufficient conditions on the existence of robust stochastic stability and γ-disturbance attenuation H∞ property are presented. A key feature of this scheme is that the gain matrices of controller are only based on It, the observed projection of the current regime rt. 展开更多
关键词 鲁棒控制 Markovian过程 跳跃参数 稳定性
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Robust H-infinity fault-tolerant control for uncertain descriptor systems by dynamical compensators 被引量:7
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作者 BingLIANG GuangrenDUAN 《控制理论与应用(英文版)》 EI 2004年第3期288-292,共5页
The problem of robust H-infinity fault-tolerant control against sensor failures for a class of uncertain descriptor systems via dynamical compensators is considered. Based on H-infinity theory in descriptor systems, a... The problem of robust H-infinity fault-tolerant control against sensor failures for a class of uncertain descriptor systems via dynamical compensators is considered. Based on H-infinity theory in descriptor systems, a sufficient condition for the existence of dynamical compensators with H-infinity fault-tolerant function is derived and expressions for the gain matrices in the compensators are presented. The dynamical compensator guarantees that the resultant colsed-loop system is admissible; furthermore, it maintains certain H-infinity norm performance in the normal condition as well as in the event of sensor failures and parameter uncertainties. A numerical example shows the effect of the proposed method. 展开更多
关键词 Fault-tolerant control h-infinity control Uncertain descriptor systems Sensor failures
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H_∞ Control for 2-D Discrete State Delayed Systems in the Second FM Model 被引量:3
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作者 XU Jian-Ming YU Li 《自动化学报》 EI CSCD 北大核心 2008年第7期809-813,共5页
这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个... 这份报纸涉及 H 控制的问题为二维(2-D ) 分离州的延期系统由第二 Fornasini 和 Marchesini (FM ) 描述了州空间当模特儿。为这个 2-D 系统有 H 噪音变细的一个足够的条件以某个线性矩阵不平等(LMI ) 被给。最佳的 H 控制器被解决一个凸的优化问题获得。最后,一个模拟例子被给说明建议结果的有效性。 展开更多
关键词 二维离散系统 控制方法 计算方法 自动化技术 智能系统
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Stability Analysis of Continuous-time Iterative Learning Control Systems with Multiple State Delays 被引量:11
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作者 MENG De-Yuan JIA Ying-Min +1 位作者 DU Jun-Ping YU Fa-Shan 《自动化学报》 EI CSCD 北大核心 2010年第5期696-703,共8页
关键词 连续系统 稳定性 自动化 TDS
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Sliding mode H_∞ control for a class of uncertain nonlinear state-delayed systems 被引量:4
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作者 Wu Ligang Wang Changhong Gao Huijun Zhang Lixian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期576-585,共10页
A new proportional-integral (PI) sliding surface is designed for a class of uncertain nonlinear state-delayed systems. Based on this, an adaptive sliding mode controller (ASMC) is synthesized, which guarantees the... A new proportional-integral (PI) sliding surface is designed for a class of uncertain nonlinear state-delayed systems. Based on this, an adaptive sliding mode controller (ASMC) is synthesized, which guarantees the occurrence of sliding mode even when the system is undergoing parameter uncertainties and external disturbance. The resulting sliding mode has the same order as the original system, so that it becomes easy to solve the H∞ control problem by designing a memoryless H∞ state feedback controller. A delay-dependent sufficient condition is proposed in terms of linear matrix inequalities (LMIs), which guarantees the sliding mode robust asymptotically stable and has a noise attenuation level γ in an H∞ sense. The admissible state feedback controller can be found by solving a sequential minimization problem subject to LMI constraints by applying the cone complementary linearization method. This design scheme combines the strong robustness of the sliding mode control with the H∞ norm performance. A numerical example is given to illustrate the effectiveness of the proposed scheme. 展开更多
关键词 sliding mode control h control NONLINEARITY state-delayed system linear matrix inequality (LMIs)
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Robust H_∞ Controller Design for Uncertain Neutral Systems via Dynamic Observer Based Output Feedback 被引量:5
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作者 Fatima El Haoussi El Houssaine Tissir 《International Journal of Automation and computing》 EI 2009年第2期164-170,共7页
In this paper, the dynamic observer-based controller design for a class of neutral systems with H∞ control is considered. An observer-based output feedback is derived for systems with polytopic parameter uncertaintie... In this paper, the dynamic observer-based controller design for a class of neutral systems with H∞ control is considered. An observer-based output feedback is derived for systems with polytopic parameter uncertainties. This controller assures delay-dependent stabilization and H∞ norm bound attenuation from the disturbance input to the controlled output. Numerical examples are provided for illustration and comparison of the proposed conditions. 展开更多
关键词 Neutral systems delay-dependent conditions h control design OBSERVER linear matrix inequality (LMI) time varyingdelay systems polytopic uncertainties.
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Acceleration Feedback Enhanced H_∞Disturbance Attenuation Control for a Class of Nonlinear Underactuated Vehicle Systems 被引量:3
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作者 HE Yu-Qing HAN Jian-Da 《自动化学报》 EI CSCD 北大核心 2008年第5期558-564,共7页
在这篇论文,一个概括加速反馈控制(声频抗流圈) 设计方法,命名声频抗流圈提高了 H ∞控制器,为两个被建议完整激活并且在激活的非线性的自治车辆系统下面。声频抗流圈基于已知的动力学作为柔韧的改进被设计到正常控制。首先,以便拒... 在这篇论文,一个概括加速反馈控制(声频抗流圈) 设计方法,命名声频抗流圈提高了 H ∞控制器,为两个被建议完整激活并且在激活的非线性的自治车辆系统下面。声频抗流圈基于已知的动力学作为柔韧的改进被设计到正常控制。首先,以便拒绝不确定性和外部骚乱,线性 prefilter 在新声频抗流圈设计方法被使用在正常声频抗流圈代替高获得。然后,背走算法被用于 AFC 设计在激活的系统下面。两个的分析在有限获得 L2 稳定性显示出的频率领域和输入产量的骚乱变细新控制器设计方法是适用的。最后,模拟关于无人的模型直升飞机的追踪的控制被进行。结果与没有声频抗流圈,追踪的控制获得验证新方法的可行性的那些相比。 展开更多
关键词 干扰弱化 加速反馈控制 非线性h∞控制 自动控制系统
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