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110m高墩施工控制测量 被引量:1
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作者 蒋临安 《铁道标准设计》 北大核心 2000年第8期1-3,共3页
介绍花土坡特大桥从布设控测网到控测网精度校核、控测网平差、控测表的绘制、激光铅直仪的安放及使用等一系列过程 ,并详细介绍控测网精度校核。
关键词 控测网 精度校核 桥梁 高墩 施工
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NEURAL NETWORK PREDICTIVE CONTROL WITH HIERARCHICAL GENETIC ALGORITHM
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作者 刘宝坤 王慧 李光泉 《Transactions of Tianjin University》 EI CAS 1998年第2期48-50,共3页
A kind of predictive control based on the neural network(NN) for nonlinear systems with time delay is addressed.The off line NN model is obtained by using hierarchical genetic algorithms (HGA) to train a sequence da... A kind of predictive control based on the neural network(NN) for nonlinear systems with time delay is addressed.The off line NN model is obtained by using hierarchical genetic algorithms (HGA) to train a sequence data of input and output.Output predictions are obtained by recursively mapping the NN model.The error rectification term is introduced into a performance function that is directly optimized while on line control so that it overcomes influences of the mismatched model and disturbances,etc.Simulations show the system has good dynamic responses and robustness. 展开更多
关键词 neural networks(NN) predictive control hierarchical genetic algorithms nonlinear system
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Computer Network Control System in Automatic Automobile Detection
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作者 高岩 窦丽华 +1 位作者 高琪 周宁 《Journal of Beijing Institute of Technology》 EI CAS 2001年第4期406-411,共6页
An automobile test controlling and managing system with computer network is introduced. The architecture of the local network, hardware structure, software structure, design of the test process, and error tolerating r... An automobile test controlling and managing system with computer network is introduced. The architecture of the local network, hardware structure, software structure, design of the test process, and error tolerating redundant design in work position substituting are presented. At last, the pivotal questions solved are discussed. With an advanced structure, this system is multi functional and flexible. Furthermore, advanced computer technology is adopted to improve its technical degree. 展开更多
关键词 computer control system local network automobile test error tolerance
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Time-stamped predictive functional control for networked control systems with random delays
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作者 张奇智 张卫东 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期149-152,共4页
The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is... The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is proposed,which generalizes the standard PFC algorithm to networked control systems with random delays.The algorithm uses the time-stamp method to estimate the control delay,predicts the future outputs based on a discrete time delay state space model,and drives the control law that applies to an NCS from the idea of a PFC algorithm.A networked control system was constructed based on TrueTime simulator,with which the time-stamped PFC algorithm was compared with the standard PFC algorithm.The response curves show that the proposed algorithm has better control performance. 展开更多
关键词 networked control systems random delays predictive functional control industrial Ethernet
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APPLICATION OF INTELLIGENCE FORECASTING METHOD IN TRAFFIC ANALYSIS OF EGCS 被引量:2
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作者 宗群 岳有军 +1 位作者 曹燕飞 尚晓光 《Transactions of Tianjin University》 EI CAS 2000年第1期18-21,共4页
Traffic flow forecasting is an important part of elevator group control system (EGCS).This paper applies time series prediction theories based on neural networks(NN) to EGCSs traffic analysis,and establishes a time se... Traffic flow forecasting is an important part of elevator group control system (EGCS).This paper applies time series prediction theories based on neural networks(NN) to EGCSs traffic analysis,and establishes a time series NN traffic flow forecasting model.Simulation results show its validity. 展开更多
关键词 traffic flow time series FORECAST elevator group control system neural networks
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Robust model predictive control with randomly occurred networked packet loss in industrial cyber physical systems 被引量:8
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作者 CAI Hong-bin LI Ping +1 位作者 SU Cheng-li CAO Jiang-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第7期1921-1933,共13页
For a class of linear discrete-time systems that is subject to randomly occurred networked packet loss in industrial cyber physical systems, a novel robust model predictive control method with active compensation mech... For a class of linear discrete-time systems that is subject to randomly occurred networked packet loss in industrial cyber physical systems, a novel robust model predictive control method with active compensation mechanism was proposed. The probability distribution of packet loss is described as the Bernoulli distributed white sequences. By using the Lyapunov stability theory, the existing sufficient conditions of the controller are derived from solving a group of linear matrix inequalities. Moreover, dropout-rate with uncertainty and unknown dropout-rate are also considered, which can greatly reduce the conservativeness of the controller. The designed robust model predictive control method not only efficiently eliminates the negative effects of the networked data loss in industrial cyber physical systems but also ensures the stability of closed-loop system. Two examples were provided to illustrate the superiority and effectiveness of the proposed method. 展开更多
关键词 robust model predictive control networked control system packet loss linear matrix inequalities (LMIs)
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A Method for Surveying Control Network Optimization Based on Reliability Properties 被引量:4
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作者 ZHANG Zhenglu DENG Yong LUO Changlin 《Geo-Spatial Information Science》 2007年第4期235-239,共5页
Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying contro... Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying control network simulation optimization design is proposed. This method is based on the inner reliability index of the observation values. 展开更多
关键词 surveying control network optimization design RELIABILITY redundant observation weight
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On Applications of Selenodesy to Lunar Detection 被引量:1
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作者 WEI Erhu LIU Jingnan 《Geo-Spatial Information Science》 2006年第3期162-170,共9页
According to the history of lunar detection, the relationship between selenodesy and lunar detection is reviewed , and the focus of the lunar detection and the lunar detection plan of China are summarized. The key tec... According to the history of lunar detection, the relationship between selenodesy and lunar detection is reviewed , and the focus of the lunar detection and the lunar detection plan of China are summarized. The key techniques of selenodesy are presented, and the applications of selenodesy to the lunar detection are discussed. 展开更多
关键词 selenodesy lunar detection lunar orbit lunar gravity field lunar reference frame lunar control network lunar topography
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The REMO Ocean Data Assimilation System into HYCOM(RODAS_H):General Description and Preliminary Results 被引量:1
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作者 Clemente Augusto Souza TANAJURA Alex Novaes SANTANA +3 位作者 Davi MIGNAC Leonardo Nascimento LIMA Konstantin BELYAEV XIE Ji-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第5期464-470,共7页
The first version of the Brazilian Oceano- graphic Modeling and Observation Network (REMO) ocean data assimilation system into the Hybrid Coordi- nate Ocean Model (HYCOM) (RODAS H) has recently been constructed ... The first version of the Brazilian Oceano- graphic Modeling and Observation Network (REMO) ocean data assimilation system into the Hybrid Coordi- nate Ocean Model (HYCOM) (RODAS H) has recently been constructed for research and operational purposes. The system is based on a multivariate Ensemble Optimal Interpolation (EnOI) scheme and considers the high fre- quency variability of the model error co-variance matrix. The EnOl can assimilate sea surface temperature (SST), satellite along-track and gridded sea level anomalies (SLA), and vertical profiles of temperature (T) and salinity (S) from Argo. The first observing system experiment was carried out over the Atlantic Ocean (78°S-50°N, 100°W-20°E) with HYCOM forced with atmospheric reanalysis from 1 January to 30 June 2010. Five integra- tions were performed, including the control run without assimilation. In the other four, different observations were assimilated: SST only (A SST); Argo T-S profiles only (AArgo); along-track SLA only (A_SLA); and all data employed in the previous runs (A_All). The A_SST, A_Argo, and A_SLA runs were very effective in improv- ing the representation of the assimilated variables, but they had relatively little impact on the variables that were not assimilated. In particular, only the assimilation of S was able to reduce the deviation of S with respect to ob- servations. Overall, the A_All run produced a good analy- sis by reducing the deviation of SST, T, and S with respect to the control run by 39%, 18%, and 30%, respectively, and by increasing the correlation of SLA by 81%. 展开更多
关键词 ocean data assimilation ensemble optimalinterpolation observing system experiment HYCOM Atlantic Ocean
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Behavior Measurement Model Based on Prediction and Control of Trusted Network 被引量:5
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作者 Gong Bei Zhang Jianbiao +1 位作者 Shen Changxiang Zhang Xing 《China Communications》 SCIE CSCD 2012年第5期117-128,共12页
In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation... In order to construct the trusted network and realize the trust of network behavior,a new multi-dimensional behavior measurement model based on prediction and control is presented.By using behavior predictive equation,individual similarity function,group similarity function,direct trust assessment function,and generalized predictive control,this model can guarantee the trust of an end user and users in its network.Compared with traditional measurement model,the model considers different characteristics of various networks.The trusted measurement policies established according to different network environments have better adaptability.By constructing trusted group,the threats to trusted group will be reduced greatly.Utilizing trusted group to restrict individuals in network can ensure the fault tolerance of trustworthiness of trusted individuals and group.The simulation shows that this scheme can support behavior measurement more efficiently than traditional ones and the model resists viruses and Trojans more efficiently than older ones. 展开更多
关键词 trusted network behavioral predic-tive control SIMILARITY trust measurement
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Experimental Evaluation of TCP and ICMP in Network Measurement
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作者 黎文伟 张大方 +1 位作者 谢高岗 杨金民 《Journal of Donghua University(English Edition)》 EI CAS 2005年第3期7-17,共11页
Network measurement is an important approach to understand network behaviors, which has been widely studied. Both Transfer Control Protocol (TCP) and Interact Control Messages Protocol (ICMP) are applied in networ... Network measurement is an important approach to understand network behaviors, which has been widely studied. Both Transfer Control Protocol (TCP) and Interact Control Messages Protocol (ICMP) are applied in network measurement, while investigating the differences between the measured results of these two protocols is an important topic that has been less investigated. In this paper, to compare the differences between TCP and ICMP when they are used in measuring host connectivity, RTT, and packet loss rate, two groups of comparison programs have been designed, and after careful evaluation of the program parameters, a lot of comparison experiments are executed on the Internet. The experimental results show that, there are significant differences between the host connectivity measured using TCP or ICMP; in general, the accuracy of connectivity measured using TCP is 20%- 30% higher than that measured using ICMP. The case of RTT and packet loss rate is complicated, which are related to path loads and destination host loads. While commonly, the RTF and packet loss rate" measured using TCP or ICMP are very close. According to the experimental results, some advices are also given on protocol selection for conducting accurate connectivity, RTF and packet loss rate measurements. 展开更多
关键词 network measurement network performance performance measurement TCP ICMP
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Fuzzy NN based predictive control and its application to green liquor system 被引量:1
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作者 李江 周伟 +1 位作者 张良军 李平 《Journal of Zhejiang University Science》 CSCD 2002年第1期57-59,共3页
The fuzzy NN predictive control algorithm introduced in this paper uses fuzzy neural network to model the nonlinear MIMO process. Its training method that integrates LS and BP algorithm brings quick convergence. GPC a... The fuzzy NN predictive control algorithm introduced in this paper uses fuzzy neural network to model the nonlinear MIMO process. Its training method that integrates LS and BP algorithm brings quick convergence. GPC algorithm is used as the predictive component. The fuzzy neural network has six layers, including input layer, output layer and four hidden layers. An application to a MIMO nonlinear process(green liquor system of the recovery system in a pulp factory shows that this algorithm has better performance than normal PID algrithm. 展开更多
关键词 model predictive control fuzzy neural networks generalized predictive control
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Study on Network Security Architecture for Power Systems 被引量:2
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作者 Chen Yan Li Zengzhi Liao Zhigang 《Electricity》 2005年第3期47-49,共3页
The wide application of network technology in power systems brings not only convenience and flexibility but also security threats. An architecture of network security for power system was proposed in this study,which ... The wide application of network technology in power systems brings not only convenience and flexibility but also security threats. An architecture of network security for power system was proposed in this study,which protected data and facilities from being attacked by outside users by means of firewall, security monitor and control system. Firewall was basically the first line of defense for the intranet; the security monitoring system was a kind of IDS (Intrusion Detection System), while security control system provided authentication, authorization,data-encrypted transmission and security management. This architecture provides various security services, such as identification, authentication, authorization, data integrity and confidentiality. 展开更多
关键词 network security power system IDS FIREWALL
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Application of generalized predictive control in networked control system 被引量:1
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作者 杨灿 朱善安 +1 位作者 孔万增 卢立明 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期225-233,共9页
A new framework for networked control system based on Generalized Predictive Control (GPC) is proposed in this paper. Clock-driven sensors, event-driven controller, and clock-driven actuators are required in this fram... A new framework for networked control system based on Generalized Predictive Control (GPC) is proposed in this paper. Clock-driven sensors, event-driven controller, and clock-driven actuators are required in this framework. A queuing strategy is proposed to overcome the network induced delay. Without redesigning, the proposed framework enables the existing GPC controller to be used in a network environment. It also does not require clock synchronization and is only slightly affected by bad network condition such as package loss. Various experiments are designed over the real network to test the proposed approach, which verify that the proposed approach can stabilize the Networked Control System (NCS) and is robust. 展开更多
关键词 Networked Control System (NCS) Generalized Predictive Control (GPC) Queuing strategy
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Method of spillover identification in urban street networks using loop detector outputs 被引量:5
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作者 马东方 王殿海 +2 位作者 孙锋 别一鸣 金盛 《Journal of Central South University》 SCIE EI CAS 2013年第2期572-578,共7页
Quick and reliable identification of the traffic state is of critical importance to traffic control systems, especially when spillovers appear. Firstly, a calculation method for the occupancy per cycle under different... Quick and reliable identification of the traffic state is of critical importance to traffic control systems, especially when spillovers appear. Firstly, a calculation method for the occupancy per cycle under different traffic conditions were presented, based on the relationship between the three basic traffic flow parameters, speed, traffic flow and density. Secondly, the times at which the stopping and starting waves approach a loop detector were confirmed using the traffic wave models modified by a kinematic equation. Then, the threshold of occupancy, which characterizes the appearance of spillovers, was determined by the premise that the stopping and starting waves had the same speed. At last, the accuracy and usability of the new method were verified by VISSIM simulation, using the ratio of misjudgment as the evaluation index. The results show that the ratio of misjudgment of the new method is about 11.36% compared to 17.65% of the previous method. 展开更多
关键词 OCCUPANCY SPILLOVER shock wave queue length SIMULATION
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Parameters determination and bolting control of gateway floor 被引量:1
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作者 GOU Pan-feng XIN Ya-jun 《Journal of Coal Science & Engineering(China)》 2011年第4期388-392,共5页
Gateway floor heave control is the key to guarantee mine safe and efficient production. Through analysis of floor instability characteristics and bolting control, gateway floor strata show second level stress under ab... Gateway floor heave control is the key to guarantee mine safe and efficient production. Through analysis of floor instability characteristics and bolting control, gateway floor strata show second level stress under abutment pressure, which causes plastic flow failure in floor strata; gateway floor instability shows mainly shear-break slippage of "triangle sliding body". Mechanics of floor bolting is mainly a function of connection and combination. Main area of bolting control lies in two gateway floor angles. The paper analyzes mechanics principle of gateway floor instability, constructs stability mechanics model of gateway floor bolting, obtains gateway floor stability criterion of different bolting angles and optimum formula of bolting parameters, carries out the engineering example, and guides better field application. It provides theoretical base for bolting gateway floor instability control. 展开更多
关键词 parameter determination BOLTING gateway floor heave mechanical model judge criterion
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Nonlinear model predictive control based on hyper chaotic diagonal recurrent neural network 被引量:1
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作者 Samira Johari Mahdi Yaghoobi Hamid RKobravi 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第1期197-208,共12页
Nonlinear model predictive controllers(NMPC)can predict the future behavior of the under-controlled system using a nonlinear predictive model.Here,an array of hyper chaotic diagonal recurrent neural network(HCDRNN)was... Nonlinear model predictive controllers(NMPC)can predict the future behavior of the under-controlled system using a nonlinear predictive model.Here,an array of hyper chaotic diagonal recurrent neural network(HCDRNN)was proposed for modeling and predicting the behavior of the under-controller nonlinear system in a moving forward window.In order to improve the convergence of the parameters of the HCDRNN to improve system’s modeling,the extent of chaos is adjusted using a logistic map in the hidden layer.A novel NMPC based on the HCDRNN array(HCDRNN-NMPC)was proposed that the control signal with the help of an improved gradient descent method was obtained.The controller was used to control a continuous stirred tank reactor(CSTR)with hard-nonlinearities and input constraints,in the presence of uncertainties including external disturbance.The results of the simulations show the superior performance of the proposed method in trajectory tracking and disturbance rejection.Parameter convergence and neglectable prediction error of the neural network(NN),guaranteed stability and high tracking performance are the most significant advantages of the proposed scheme. 展开更多
关键词 nonlinear model predictive control diagonal recurrent neural network chaos theory continuous stirred tank reactor
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Chinese Surveying and Control Network for Earth-Orbit Satellites and Deep Space Detection
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作者 WEI Erhu LIU Jingnan SHI Chuang 《Geo-Spatial Information Science》 2006年第1期6-12,37,共8页
The relationship between the surveying and contro l network(CSN) for earth-orbit satellite and spatial geodesy, and the relationshi p between the CSN for deep space celestial bodies and detectors, and deep space detec... The relationship between the surveying and contro l network(CSN) for earth-orbit satellite and spatial geodesy, and the relationshi p between the CSN for deep space celestial bodies and detectors, and deep space detection are briefly summarized, and so are the basic technical needs of the de ep space surveying and control network(DSN). Then, the techniques, the constitue nts and the distributing of Chinese satellite CSN (CSCSN) and other radio observ ing establishments in China are introduced. Lastly, with the primary CSCSN and o ther observing establishments, some projects for China to rebuild a more perfect CSCSN, and to establish a DSN are analyzed and stated. 展开更多
关键词 satellite surveying and control network DSN microwave radio radar LLR DSCCs radio observation space-based station
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Interference management via access control and mobility prediction in two-tier heterogeneous networks 被引量:1
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作者 肖竹 陈杰 +2 位作者 王东 李仁发 易克初 《Journal of Central South University》 SCIE EI CAS 2014年第8期3169-3177,共9页
Abstract: Two-tier heterogeneous networks (HetNets), where the current cellular networks, i.e., macrocells, are overlapped with a large number of randomly distributed femtocells, can potentially bring significant b... Abstract: Two-tier heterogeneous networks (HetNets), where the current cellular networks, i.e., macrocells, are overlapped with a large number of randomly distributed femtocells, can potentially bring significant benefits to spectral utilization and system capacity. The interference management and access control for open and closed femtocells in two-tier HetNets were focused. The contributions consist of two parts. Firstly, in order to reduce the uplink interference caused by MUEs (macrocell user equipments) at closed femtocells, an incentive mechanism to implement interference mitigation was proposed. It encourages femtoeells that work with closed-subscriber-group (CSG) to allow the interfering MUEs access in but only via uplink, which can reduce the interference significantly and also benefit the marco-tier. The interference issue was then studied in open-subscriber-group (OSG) femtocells from the perspective of handover and mobility prediction. Inbound handover provides an alternative solution for open femtocells when interference turns up, while this accompanies with PCI (physical cell identity) confusion during inbound handover. To reduce the PCI confusion, a dynamic PCI allocation scheme was proposed, by which the high handin femtocells have the dedicated PCI while the others share the reuse PCIs. A Markov chain based mobility prediction algorithm was designed to decide whether the femtoeell status is with high handover requests. Numerical analysis reveals that the UL interference is managed well for the CSG femtocell and the PCI confusion issue is mitigated greatly in OSG femtocell compared to the conventional approaches. 展开更多
关键词 FEMTOCELL MACROCELL interference management heterogeneous networks access control HANDOVER mobility prediction
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A Delay System Approach to Fault Detection Filter of Networked Control Systems 被引量:1
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作者 马力伟 田作华 +1 位作者 施颂椒 翁正新 《Journal of Donghua University(English Edition)》 EI CAS 2009年第1期21-25,共5页
In this paper,the fault detection filter(FDF) design problem for networked control systems(NCSs) with both network-induced delay and data dropout is studied.Based on a new NCSs model proposed recently,an observer-base... In this paper,the fault detection filter(FDF) design problem for networked control systems(NCSs) with both network-induced delay and data dropout is studied.Based on a new NCSs model proposed recently,an observer-based filter is introduced to be the residual generator and formulated as an H∞-optimization problem for systems with two successive delay components.By applying Lyapunov-Krasovskii approach,a new sufficient condition on stability and H∞ performance is derived for systems with two successive delay components in the state.A solution of the optimization problem is then presented in terms of linear matrix inequality(LMI) formulation,dependently of time delay.In order to detect the fault,the residual evaluation problem is also considered.An illustrative design example is employed to demonstrate the validity of the proposed approach. 展开更多
关键词 fault detection filter (FDF) networkedcontrol systems (NCSs) H∞ -optimization delay system linear matrix inequality (LMI)
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