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Study on nitrogen pollution in waterbodies and it's control strategy
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《Global Geology》 1998年第1期28-28,共1页
关键词 study on nitrogen pollution in waterbodies and it’s control strategy
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Synchronous Control of Complex Networks with Fuzzy Connections
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作者 Wei Chen Yuanguang Zheng 《Open Journal of Applied Sciences》 2023年第12期2273-2281,共9页
This article is based on the T-S fuzzy control theory and investigates the synchronization control problem of complex networks with fuzzy connections. Firstly, the main stability equation of a complex network system i... This article is based on the T-S fuzzy control theory and investigates the synchronization control problem of complex networks with fuzzy connections. Firstly, the main stability equation of a complex network system is obtained, which can determine the stability of the synchronous manifold. Secondly, the main stable system is fuzzified, and based on fuzzy control theory, the control design of the fuzzified main stable system is carried out to obtain a coupling matrix that enables the complex network to achieve complete synchronization. The numerical analysis results indicate that the control method proposed in this paper can effectively achieve synchronization control of complex networks, while also controlling the transition time for the network to achieve synchronization. 展开更多
关键词 T-s Fuzzy control sYNCHRONIZATION Complex Network
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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change sea level variance X-bar s control charts
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Fuzzy modelling and impulsive control of the hyperchaotic L system 被引量:1
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作者 张小洪 李东 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1774-1779,共6页
This paper presents a novel approach to hyperchaos control of hyperchaotic systems based on impulsive control and the Takagi-Sugeno (T-S) fuzzy model. In this study, the hyperchaotic Lu system is exactly represented... This paper presents a novel approach to hyperchaos control of hyperchaotic systems based on impulsive control and the Takagi-Sugeno (T-S) fuzzy model. In this study, the hyperchaotic Lu system is exactly represented by the T-S fuzzy model and an impulsive control framework is proposed for stabilizing the hyperchaotic Lu system, which is also suitable for classes of T-S fuzzy hyperchaotic systems, such as the hyperchaotic Rossler, Chen, Chua systems and so on. Sufficient conditions for achieving stability in impulsive T-S fuzzy hyperchaotic systems are derived by using Lyapunov stability theory in the form of the linear matrix inequality, and are less conservative in comparison with existing results. Numerical simulations are given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 hyperchaos control impulsive control T-s fuzzy model linear matrix inequalities
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A Novel Stateful PCE-Cloud Based Control Architecture of Optical Networks for Cloud Services 被引量:1
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作者 QIN Panke CHEN Xue +1 位作者 WANG Lei WANG Liqian 《China Communications》 SCIE CSCD 2015年第10期117-127,共11页
The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features ... The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed. 展开更多
关键词 optical networks control plane GMPLs stateful PCE cloud computing Qo s
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车辆主动悬架自适应变论域T-S模糊控制研究
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作者 李韶华 季广港 +1 位作者 冯桂珍 王贺 《振动.测试与诊断》 EI CSCD 北大核心 2024年第4期733-739,828,共8页
针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊... 针对传统变论域模糊控制存在过度依赖专家经验、伸缩因子参数不能自适应调整的问题,提出一种车辆主动悬架自适应变论域T-S模糊控制策略,从而提高车辆的行驶平顺性。结合神经网络和T-S模糊推理建立基于自适应神经模糊推理的一阶T-S模糊控制器,利用神经网络的自学习特性产生完善的模糊规则,进而在传统函数型伸缩因子的基础上,将系统误差和误差变化率作为动态参数引入伸缩因子中,实现伸缩因子参数的自适应调整,解决了传统函数型伸缩因子因参数确定难度大导致控制效果差的问题。通过随机工况下的仿真分析和基于相似理论的缩尺实验,对所提出算法的有效性和工况自适应性进行了验证。结果表明,所提出的自适应变论域T-S模糊控制策略具有较强的工况适应性,在不同车速、路面激励下均可有效提高车辆的平顺性并保证轮胎接地安全性。 展开更多
关键词 主动悬架 变论域 伸缩因子 T-s模糊控制 神经模糊系统
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基于STM32的步进电机加减速轨迹规划算法 被引量:1
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作者 徐建明 徐金辉 《浙江工业大学学报》 CAS 北大核心 2024年第4期465-472,共8页
针对传统步进电机开环控制下加减速过程中柔性冲击大、失步和过冲等问题,结合STM32单片机提出了一种离散化的、带有电流调节的S曲线加减速控制算法。首先,通过多项式算法构建连续光滑的S曲线,根据矩频特性拟合转速和转矩的关系,联立转... 针对传统步进电机开环控制下加减速过程中柔性冲击大、失步和过冲等问题,结合STM32单片机提出了一种离散化的、带有电流调节的S曲线加减速控制算法。首先,通过多项式算法构建连续光滑的S曲线,根据矩频特性拟合转速和转矩的关系,联立转速和功率的关系,推导出电流计算方法;然后,对连续的S曲线进行等时间间隔采样,完成对S曲线的离散化;最后,在Keil平台进行算法代码编写,将编译后的工程文件下载到STM32中,通过步进电机的速度和位置跟踪实验验证了算法的有效性。 展开更多
关键词 步进电机 s曲线 加减速控制
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基于B/S架构的远程会诊质控系统的设计与应用
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作者 路阳 段燕 张雪 《中国卫生标准管理》 2024年第13期1-6,共6页
目的研发远程会诊质控系统,在区域内实现远程会诊质控、管理、监管、考评、统计和持续改进的信息化。方法2020年,组建多学科团队,运用智力激励法和专题小组讨论法,基于B/S架构研发远程会诊质控系统,与既有远程会诊信息系统完全嵌合兼容... 目的研发远程会诊质控系统,在区域内实现远程会诊质控、管理、监管、考评、统计和持续改进的信息化。方法2020年,组建多学科团队,运用智力激励法和专题小组讨论法,基于B/S架构研发远程会诊质控系统,与既有远程会诊信息系统完全嵌合兼容,满足远程会诊全流程质量管理的功能需求。结果针对远程会诊质控工作要求,系统设计研发了质控管理、质控考评、实时监管、统计分析4个子模块,可满足远程会诊全流程质量管理的功能需求。结论该质控系统创新了远程会诊信息化质量管理模式,在区域内实现了远程会诊全流程的信息化管理,取得了较好的质量管理成效,有效促进区域内远程会诊工作的推进和发展。 展开更多
关键词 远程会诊 B/s架构 质量控制 信息系统 设计 应用
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基于Super-Twisting滑模S面的无人机路径跟踪控制
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作者 张国兵 石上瑶 +2 位作者 李佳成 常哲 陈鹏云 《火力与指挥控制》 CSCD 北大核心 2024年第2期11-17,共7页
针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控... 针对小型固定翼无人机在执行任务时跟踪精度低以及容易受外界风影响的问题,设计基于Super-Twisting滑模S面(STSM S-Plane)的路径跟踪控制器,同时采用内外双环控制模式。外环即速度环采用Super-Twisting滑模控制,内环即姿态环采用S面控制。考虑到S面控制求导易导致积分爆炸的问题引入了二阶微分器,并对外界风组成进行建模研究。最后通过空间特殊曲线来验证所设计算法的控制性能。仿真结果表明,所设计的算法可以实现固定翼无人机对期望路径的精确跟踪,并具有良好的鲁棒性和抗干扰性能。 展开更多
关键词 固定翼无人机 super-Twisting滑模 s面控制 风干扰
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售货机升降系统S型速度控制策略
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作者 冯高明 邱文仙 金明磊 《电子科技》 2024年第5期54-61,共8页
在传统三闭环控制方式下,售货机升降接货系统易因启停过程中加速度突变产生冲击,导致系统运行不平稳。针对这一问题,文中对传统升降系统加减速控制策略进行改进,加入前馈和微分负反馈,提出一种S型速度曲线控制算法。根据路径规划判别条... 在传统三闭环控制方式下,售货机升降接货系统易因启停过程中加速度突变产生冲击,导致系统运行不平稳。针对这一问题,文中对传统升降系统加减速控制策略进行改进,加入前馈和微分负反馈,提出一种S型速度曲线控制算法。根据路径规划判别条件将S型速度曲线分为七段式、六段式和四段式3种,并给出各路径约束条件下的参数求解方法和具体执行流程。将该算法运用到升降控制系统中进行仿真和实际工况测试,实验结果表明,与传统三闭环控制相比,文中所提控制策略可以提高售货机升降系统运行的平稳性,减小冲击,使速度曲线更加柔和,并能够保持较好的跟踪性能。 展开更多
关键词 加减速控制 s型速度曲线 升降系统 加速度突变 冲击 售货机 控制策略 跟踪性能
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Improved S Surface Controller and Semi-physical Simulation for AUV 被引量:2
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作者 吕翀 庞永杰 +1 位作者 李晔 张磊 《Journal of Marine Science and Application》 2010年第3期301-306,共6页
S surface controllers have been proven to provide effective motion control for an autonomous underwater vehicle (AUV).However, it is difficult to adjust their control parameters manually.Choosing the optimum parameter... S surface controllers have been proven to provide effective motion control for an autonomous underwater vehicle (AUV).However, it is difficult to adjust their control parameters manually.Choosing the optimum parameters for the controller of a particular AUV is a significant challenge.To automate the process, a modified particle swarm optimization (MPSO) algorithm was proposed.It was based on immune theory, and used a nonlinear regression strategy for inertia weight to optimize AUV control parameters.A semi-physical simulation system for the AUV was developed as a platform to verify the proposed control method, and its structure was considered.The simulation results indicated that the semi-physical simulation platform was helpful, the optimization algorithm has good local and global searching abilities, and the method can be reliably used for an AUV. 展开更多
关键词 s surface controller AUV MPsO semi-physical simulation
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Changes in sediment discharge in a sediment-rich region of the Yellow River from 1955 to 2010: implications for further soil erosion control 被引量:7
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作者 JuYing JIAO ZhiJie WANG +2 位作者 GuangJu ZHAO WanZhong WANG XingMin MU 《Journal of Arid Land》 SCIE CSCD 2014年第5期540-549,共10页
The well-documented decrease in the discharge of sediment into the Yellow River has attracted considerable attention in recent years. The present study analyzed the spatial and temporal variation of sediment yield bas... The well-documented decrease in the discharge of sediment into the Yellow River has attracted considerable attention in recent years. The present study analyzed the spatial and temporal variation of sediment yield based on data from 46 hydrological stations in the sediment-rich region of the Yellow River from 1955 to 2010. The results showed that since 1970 sediment yield in the region has clearly decreased at different rates in the 45 sub-areas controlled by hydrological stations. The decrease in sediment yield was closely related to the intensity and extent of soil erosion control measures and rainstorms that occurred in different periods and sub-areas. The average sediment delivery modulus(SDM) in the study area decreased from 7,767.4 t/(km^2·a) in 1951–1969 to 980.5 t/(km^2·a) in 2000–2010. Our study suggested that 65.5% of the study area with the SDM below 1,000 t/(km^2·a) is still necessary to control soil deterioration caused by erosion, and soil erosion control measures should be further strengthened in the areas with the SDM above 1,000 t/(km^2·a). 展开更多
关键词 sediment delivery modulussDM) Yellow River hydrological station(s)-controlled sub-area soil and water conservation
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Gα_s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt/β-catenin signaling 被引量:8
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作者 Ruoshi Xu Sanjoy Kumar Khan +4 位作者 Taifeng Zhou Bo Gao Yaxing Zhou Xuedong Zhou Yingzi Yang 《Bone Research》 CAS CSCD 2018年第4期340-354,共15页
How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated i... How osteoblast cells are induced is a central question for understanding skeletal formation. Abnormal osteoblast differentiation leads to a broad range of devastating craniofacial diseases. Here we have investigated intramembranous ossification during cranial bone development in mouse models of skeletal genetic diseases that exhibit craniofacial bone defects. The GNAS gene encodes Gαs that transduces GPCR signaling. GNAS activation or loss-of-function mutations in humans cause fibrous dysplasia(FD) or progressive osseous heteroplasia(POH) that shows craniofacial hyperostosis or craniosynostosis, respectively. We find here that, while Hh ligand-dependent Hh signaling is essential for endochondral ossification, it is dispensable for intramembranous ossification, where Gαsregulates Hh signaling in a ligand-independent manner. We further show that Gαscontrols intramembranous ossification by regulating both Hh and Wnt/β-catenin signaling. In addition, Gαsactivation in the developing cranial bone leads to reduced ossification but increased cartilage presence due to reduced cartilage dissolution, not cell fate switch. Small molecule inhibitors of Hh and Wnt signaling can effectively ameliorate cranial bone phenotypes in mice caused by loss or gain of Gnas function mutations, respectively. Our work shows that studies of genetic diseases provide invaluable insights in both pathological bone defects and normal bone development, understanding both leads to better diagnosis and therapeutic treatment of bone diseases. 展开更多
关键词 s signaling controls intramembranous ossification during cranial bone development by regulating both Hedgehog and Wnt catenin signaling
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Reliable Fuzzy Control for a Class of Nonlinear Networked Control Systems with Time Delay 被引量:23
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作者 FENG Jian WANG Shen-Quan 《自动化学报》 EI CSCD 北大核心 2012年第7期1091-1099,共9页
关键词 网络控制系统 状态时滞 模糊控制 非线性 LYAPUNOV泛函 线性矩阵不等式 网络诱导时延 执行器故障
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Design of Novel S-plane Controller of Autonomous Underwater Vehicle Established on Sliding Mode Control 被引量:2
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作者 Chunmeng Jiang Lei Wan Yushan Sun 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第2期58-64,共7页
Based on the deep analysis of the mathematical model of an autonomous underwater vehicle( AUV),comprehensive considerations are given to the coupling effect of AUV's longitudinal velocity on the other degrees of f... Based on the deep analysis of the mathematical model of an autonomous underwater vehicle( AUV),comprehensive considerations are given to the coupling effect of AUV's longitudinal velocity on the other degrees of freedom. In the meantime,discussions are made on the influence of residual buoyancy and restoring moment.A novel S-plane controller established on sliding mode control( SMC) is hereby proposed in this study. The strengths of traditional S-plane controller including simple structure and easily adjustable parameters are maintained in the improved design while the weakness of unsatisfactory control effect at the time of high-speed operation is also overcome. Lyapunov function is introduced to make the stability analysis of the controller before it is successfully applied to the basic motion control of AUV-X. Then the comparative experiment test is carried out between the traditional S-plane controller and the novel S-plane controller. The effectiveness and feasibility of the novel S-plane controller established on sliding mode control in the AUV basic motion control is verified by the comparative analysis of experiment results. 展开更多
关键词 sliding mode control s-plane controller stability analysis Lyapunov function autonomous underwater vehicle
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Fault tolerant controlled quantum dialogue against collective noise 被引量:3
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作者 Li-Wei Chang Yu-Qing Zhang +2 位作者 Xiao-Xiong Tian Yu-Hua Qian Shi-Hui Zheng 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期128-139,共12页
Quantum system is inevitably affected by the external environment in the real world.Two controlled quantum dialogue protocols are put forward based on logicalχ-type states under collective noise environment.One is ag... Quantum system is inevitably affected by the external environment in the real world.Two controlled quantum dialogue protocols are put forward based on logicalχ-type states under collective noise environment.One is against collectivedephasing noise,while the other is against collective-rotation noise.Compared with existing protocols,there exist several outstanding advantages in our proposed protocols:Firstly,theχ-type state is utilized as quantum channels,it possesses better entanglement properties than GHZ state,W state as well as cluster state,which make it difficult to be destroyed by local operations.Secondly,two kinds of logicalχ-type states are constructed by us in theory,which can be perfectly immune to the effects of collective noise.Thirdly,the controller can be offline after quantum distribution and permission announcement,without waiting for all the participants to complete the information coding.Fourthly,the security analysis illuminates that our protocols can not only be free from the information leakage,but also resist against the interceptand-resend attack,the entanglement-and-measure attack,the modification attack,the conspiring attack,and especially the dishonest controller’s attacks. 展开更多
关键词 controlled quantum dialogue collective noise logicalχ-type state dishonest controller’s attacks
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On China's Capital Controls 被引量:1
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作者 D.Phil 《经济研究参考》 1999年第70期11-23,共13页
Ⅰ. Introduction In the wake of the Debt Crisis of the early 1980s, the World Bank pub-lished a report to summarize developing countries’ experience in utilizingforeign capital. According to the report, "Foreign... Ⅰ. Introduction In the wake of the Debt Crisis of the early 1980s, the World Bank pub-lished a report to summarize developing countries’ experience in utilizingforeign capital. According to the report, "Foreign finance can promotegrowth through higher investment and technology transfers. It can allowcountries to adjust gradually to new circumstances in the world economy. 展开更多
关键词 On China’s Capital controls MUsT BANK Us FDI THAN
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Statistic PID Tracking Control for Non-Gaussian Stochastic Systems Based on T-S Fuzzy Model 被引量:3
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作者 Yang Yi Hong Shen Lei Gu 《International Journal of Automation and computing》 EI 2009年第1期81-87,共7页
A new robust proportional-integral-derivative (PID) tracking control framework is considered for stochastic systems with non-Gaussian variable based on B-spline neural network approximation and T-S fuzzy model ident... A new robust proportional-integral-derivative (PID) tracking control framework is considered for stochastic systems with non-Gaussian variable based on B-spline neural network approximation and T-S fuzzy model identification. The tracked object is the statistical information of a given target probability density function (PDF), rather than a deterministic signal. Following B-spline approximation to the integrated performance function, the concerned problem is transferred into the tracking of given weights. Different from the previous related works, the time delay T-S fuzzy models with the exogenous disturbances are applied to identify the nonlinear weighting dynamics. Meanwhile, the generalized PID controller structure and the improved convex linear matrix inequalities (LMI) algorithms are proposed to fulfil the tracking problem. Furthermore, in order to enhance the robust performance, the peak-to-peak measure index is applied to optimize the tracking performance. Simulations are given to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Non-Gaussian systems probability density function statistic tracking control T-s fuzzy model proportional-integralderivative control.
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Delay-dependent robust H_∞ control for uncertain discrete time-delay fuzzy systems 被引量:1
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作者 Gong Cheng Su Baoku 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期354-362,共9页
The robust H∞ control problem of norm bounded uncertain discrete Takagi-Sugeno (T-S) fuzzy systems with state delay is addressed. First, by constructing an appropriate basis-dependent Lyapunov-Krasovskii function, ... The robust H∞ control problem of norm bounded uncertain discrete Takagi-Sugeno (T-S) fuzzy systems with state delay is addressed. First, by constructing an appropriate basis-dependent Lyapunov-Krasovskii function, a new delay-dependent sufficient condition on robust H∞-disturbance attenuation is presented, in which both robust stability and prescribed H∞ performance are guaranteed to be achieved. Then based on the condition, a delay-dependent robust Hoo controller design scheme is developed in term of a convex algorithm. Finally, examples are given to illustrate the effectiveness of the proposed method. 展开更多
关键词 discrete T-s fuzzy control DELAY-DEPENDENT robust H∞ control basis-dependent Lyapunov-Krasovskii function
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Numerical Investigation of Electrohydrodynamic (EHD) Flow Control in an S-Shaped Duct 被引量:7
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作者 杨晖 李锋 +1 位作者 宋耀颖 孙佰刚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第10期897-904,共8页
An electrohydrodynamic (EHD) method, which is based on glow discharge plasma, is presented for flow control in an S-shaped duct. The research subject is an expanding channel with a constant width and a rectangular c... An electrohydrodynamic (EHD) method, which is based on glow discharge plasma, is presented for flow control in an S-shaped duct. The research subject is an expanding channel with a constant width and a rectangular cross section. An equivalent divergence angle and basic function are introduced to build the three-dimensional model. Subsequently, the plasma physical models are simplified as the effects of electrical body force and work (done by the force) on the fluid near the wall. With the aid of FLUENT software, the source terms of momentum and energy are added to the Navier-Stokes equation. Finally, the original performance of three models (A, B and C) is studied, in which model A demonstrates better performance. Then EHD control based on model A is discussed. The results show that the EHD method is an effective way of reducing flow loss and improving uniformity at the duct exit. The innovation in this study is the assessment of the EHD control effect on the flow in an S-shaped duct. Both the parametric modeling of the S-shaped duct and the simplified models of plasma provide valuable information for future research on aircraft inlet ducts. 展开更多
关键词 electro hydrodynamic (EHD) s-shaped duct flow control glow discharge plasma total pressure.
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