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Research on Evaluation of Degree of Complexity of Mining Fault Network Based on GIS 被引量:5
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作者 ZHANG Hua WANG Yun-jia LIU Chuan-zhi 《Journal of China University of Mining and Technology》 EI 2007年第1期63-67,共5页
A large number of spatial and attribute data are involved in coal resource evaluation. Database is a relatively advanced data management technology, but its Major defects are the poor graphic and spatial data function... A large number of spatial and attribute data are involved in coal resource evaluation. Database is a relatively advanced data management technology, but its Major defects are the poor graphic and spatial data functions, from which it is difficult to realize scientific management of evaluation data with spatial characteristics and evaluation result maps. On account of these deficiencies, the evaluation of degree of complexity of mining fault network, based on GIS, is proposed, which integrates management of spatial and attribute data. Fractal is an index which can reflect the comprehensive information of faults' number, density, size, composition and dynamics mechanism. Fractal dimension is used as the quantitative evaluation index. Evaluation software has been developed based on a component GIS-MapX, with which the degree of complexity of fault network is evaluated quantitatively using the quantitative index of fractal dimensions in Liuqiao No.2 coal mine as an example. Results show that it is effective in acquiring model parameters and enhancing the definition of data and evaluation results with the application of GIS technology. The fault network is a system with fractal structure and its complexity can be described reasonably and accurately by fractal dimension, which provides an effective method for coal resource evaluation. 展开更多
关键词 spatial data fractal dimension fault network quantitative evaluation GIS
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Water Infiltration Study from Magnetotelluric Data in the Limestone Fault Network of Mintom (South Cameroon)
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作者 Harlin L. Ekoro Nkoungou Daniel H. Gouet +1 位作者 Philippe Njandjock Nouck Eliézer Manguelle Dicoum 《International Journal of Geosciences》 2015年第9期1007-1017,共11页
Magnetotelluric surveys have been conducted in the Mintom area in order to evaluate the water infiltration potential of the Dja river in a limestone deposit estimated at about 350 million?m3 laying on a network of fau... Magnetotelluric surveys have been conducted in the Mintom area in order to evaluate the water infiltration potential of the Dja river in a limestone deposit estimated at about 350 million?m3 laying on a network of faults compromising the exploitation of this limestone deposit. The interpretation of these data shows that this network of faults is clearly highlighted as 2D/3D structures consolidated showing a low potential water infiltration through these structures. This result is confirmed by the absence of confined and induced aquifer along all the profiles. From this finding, we concluded that the exploitation of this deposit is not conditioned by the water infiltration from the Dja River. 展开更多
关键词 LIMESTONE fault network Water INFILTRATION 2D MAGNETOTELLURIC INVERSION
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The Lightweight Edge-Side Fault Diagnosis Approach Based on Spiking Neural Network
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作者 Jingting Mei Yang Yang +2 位作者 Zhipeng Gao Lanlan Rui Yijing Lin 《Computers, Materials & Continua》 SCIE EI 2024年第6期4883-4904,共22页
Network fault diagnosis methods play a vital role in maintaining network service quality and enhancing user experience as an integral component of intelligent network management.Considering the unique characteristics ... Network fault diagnosis methods play a vital role in maintaining network service quality and enhancing user experience as an integral component of intelligent network management.Considering the unique characteristics of edge networks,such as limited resources,complex network faults,and the need for high real-time performance,enhancing and optimizing existing network fault diagnosis methods is necessary.Therefore,this paper proposes the lightweight edge-side fault diagnosis approach based on a spiking neural network(LSNN).Firstly,we use the Izhikevich neurons model to replace the Leaky Integrate and Fire(LIF)neurons model in the LSNN model.Izhikevich neurons inherit the simplicity of LIF neurons but also possess richer behavioral characteristics and flexibility to handle diverse data inputs.Inspired by Fast Spiking Interneurons(FSIs)with a high-frequency firing pattern,we use the parameters of FSIs.Secondly,inspired by the connection mode based on spiking dynamics in the basal ganglia(BG)area of the brain,we propose the pruning approach based on the FSIs of the BG in LSNN to improve computational efficiency and reduce the demand for computing resources and energy consumption.Furthermore,we propose a multiple iterative Dynamic Spike Timing Dependent Plasticity(DSTDP)algorithm to enhance the accuracy of the LSNN model.Experiments on two server fault datasets demonstrate significant precision,recall,and F1 improvements across three diagnosis dimensions.Simultaneously,lightweight indicators such as Params and FLOPs significantly reduced,showcasing the LSNN’s advanced performance and model efficiency.To conclude,experiment results on a pair of datasets indicate that the LSNN model surpasses traditional models and achieves cutting-edge outcomes in network fault diagnosis tasks. 展开更多
关键词 network fault diagnosis edge networks Izhikevich neurons PRUNING dynamic spike timing dependent plasticity learning
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Waveguide Bragg Grating for Fault Localization in PON
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作者 HU Jin LIU Xu +4 位作者 ZHU Songlin ZHUANG Yudi WU Yuejun XIA Xiang HE Zuyuan 《ZTE Communications》 2024年第2期94-98,共5页
Femtosecond laser direct inscription is a technique especially useful for prototyping purposes due to its distinctive advantages such as high fabrication accuracy,true 3D processing flexibility,and no need for mold or... Femtosecond laser direct inscription is a technique especially useful for prototyping purposes due to its distinctive advantages such as high fabrication accuracy,true 3D processing flexibility,and no need for mold or photomask.In this paper,we demonstrate the design and fabrication of a planar lightwave circuit(PLC)power splitter encoded with waveguide Bragg gratings(WBG)using a femtosecond laser inscription technique for passive optical network(PON)fault localization application.Both the reflected wavelengths and intervals of WBGs can be conveniently tuned.In the experiment,we succeeded in directly inscribing WBGs in 1×4 PLC splitter chips with a wavelength interval of about 4 nm and an adjustable reflectivity of up to 70% in the C-band.The proposed method is suitable for the prototyping of a PLC splitter encoded with WBG for PON fault localization applications. 展开更多
关键词 planar light circuit power splitter waveguide Bragg gratings femtosecond laser optical network fault localization
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Review of Artificial Intelligence for Oil and Gas Exploration: Convolutional Neural Network Approaches and the U-Net 3D Model
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作者 Weiyan Liu 《Open Journal of Geology》 CAS 2024年第4期578-593,共16页
Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Ou... Deep learning, especially through convolutional neural networks (CNN) such as the U-Net 3D model, has revolutionized fault identification from seismic data, representing a significant leap over traditional methods. Our review traces the evolution of CNN, emphasizing the adaptation and capabilities of the U-Net 3D model in automating seismic fault delineation with unprecedented accuracy. We find: 1) The transition from basic neural networks to sophisticated CNN has enabled remarkable advancements in image recognition, which are directly applicable to analyzing seismic data. The U-Net 3D model, with its innovative architecture, exemplifies this progress by providing a method for detailed and accurate fault detection with reduced manual interpretation bias. 2) The U-Net 3D model has demonstrated its superiority over traditional fault identification methods in several key areas: it has enhanced interpretation accuracy, increased operational efficiency, and reduced the subjectivity of manual methods. 3) Despite these achievements, challenges such as the need for effective data preprocessing, acquisition of high-quality annotated datasets, and achieving model generalization across different geological conditions remain. Future research should therefore focus on developing more complex network architectures and innovative training strategies to refine fault identification performance further. Our findings confirm the transformative potential of deep learning, particularly CNN like the U-Net 3D model, in geosciences, advocating for its broader integration to revolutionize geological exploration and seismic analysis. 展开更多
关键词 Deep Learning Convolutional Neural networks (CNN) Seismic fault Identification U-Net 3D Model Geological Exploration
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Fault Diagnosis for Manifold Absolute Pressure Sensor(MAP) of Diesel Engine Based on Elman Neural Network Observer 被引量:17
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作者 WANG Yingmin ZHANG Fujun +1 位作者 CUI Tao ZHOU Jinlong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期386-395,共10页
Intake system of diesel engine is a strong nonlinear system, and it is difficult to establish accurate model of intake system; and bias fault and precision degradation fault of MAP of diesel engine can't be diagnosed... Intake system of diesel engine is a strong nonlinear system, and it is difficult to establish accurate model of intake system; and bias fault and precision degradation fault of MAP of diesel engine can't be diagnosed easily using model-based methods. Thus, a fault diagnosis method based on Elman neural network observer is proposed. By comparing simulation results of intake pressure based on BP network and Elman neural network, lower sampling error magnitude is gained using Elman neural network, and the error is less volatile. Forecast accuracy is between 0.015?0.017 5 and sample error is controlled within 0?0.07. Considering the output stability and complexity of solving comprehensively, Elman neural network with a single hidden layer and with 44 nodes is presented as intake system observer. By comparing the relations of confidence intervals of the residual value between the measured and predicted values, error variance and failures in various fault types. Then four typical MAP faults of diesel engine can be diagnosed: complete failure fault, bias fault, precision degradation fault and drift fault. The simulation results show: intake pressure is observable and selection of diagnostic strategy parameter reasonably can increase the accuracy of diagnosis;the proposed fault diagnosis method only depends on data and structural parameters of observer, not depends on the nonlinear model of air intake system. A fault diagnosis method is proposed not depending system model to observe intake pressure, and bias fault and precision degradation fault of MAP of diesel engine can be diagnosed based on residuals. 展开更多
关键词 neural network diesel engine intake system fault diagnosis threshold value
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Fault Estimation and Accommodation for a Class of Nonlinear System Based on Neural Network Observer 被引量:2
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作者 Wang Ruonan Jiang Bin Liu Jianwei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第2期318-325,共8页
The problem of fault estimation and accommodation of nonlinear systems with disturbances is studied using adaptive observer and neural network techniques.A robust adaptive learning algorithm based on switchingβsmodif... The problem of fault estimation and accommodation of nonlinear systems with disturbances is studied using adaptive observer and neural network techniques.A robust adaptive learning algorithm based on switchingβsmodification is developed to realize the accurate and fast estimation of unknown actuator faults or component faults.Then a fault tolerant controller is designed to restore system performance.Dynamic error convergence and system stability can be guaranteed by Lyapunov stability theory.Finally,simulation results of quadrotor helicopter attitude systems are presented to illustrate the efficiency of the proposed techniques. 展开更多
关键词 ACTUATOR fault component fault neural network adaptive OBSERVER fault TOLERANT controller
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Network Fault Analysis from Passive Measurement 被引量:1
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作者 Huang Lisheng Wang Wenyong +1 位作者 Li Changchun Lan Yunhai 《China Communications》 SCIE CSCD 2012年第5期64-74,共11页
A new passive method for automatic dis-covery and bcation of network failure is proposed. This method employs a passive measurement to collect infonmtion and events from network traffic, and em-ploys a rrodel-based re... A new passive method for automatic dis-covery and bcation of network failure is proposed. This method employs a passive measurement to collect infonmtion and events from network traffic, and em-ploys a rrodel-based reasoning system to detect and locate network faults. Measurement points are de-ployed in a backbone network to capture the traffic and then evaluate the Quality of Service (QoS) metrics of end-to-end IP conversations. A muting rrodel is al-so established for the observed network to simulate the attributes and activities of reuters and links. This muting model also deduces the muting path for each IP conversation, and thus the QoS metrics of IP con-versations are mapped into the metrics of paths. With the inforrmtion of shared links of overlapping paths and network torrography technique, the QoS metrics of links can also be estimated, and the poorly rated links are picked out as failure points. This method is imple-mented in a tool named FaultMan, which is deployed in a campus network. Test results have shown its availa-bility in rriddle-scale networks. 展开更多
关键词 passive measurement network fault lo-cation model-based reasoning
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Fault Tolerant Control for Networked Control Systems with Packet Loss and Time Delay 被引量:5
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作者 Ming-Yue Zhao He-Ping Liu +1 位作者 Zhi-Jun Li De-Hui Sun 《International Journal of Automation and computing》 EI 2011年第2期244-253,共10页
In this paper,a fault tolerant control with the consideration of actuator fault for a networked control system (NCS) with packet loss is addressed.The NCS with data packet loss can be described as a switched system ... In this paper,a fault tolerant control with the consideration of actuator fault for a networked control system (NCS) with packet loss is addressed.The NCS with data packet loss can be described as a switched system model.Packet loss dependent Lyapunov function is used and a fault tolerant controller is proposed respectively for arbitrary packet loss process and Markovian packet loss process.Considering a controlled plant with external energy-bounded disturbance,a robust H ∞ fault tolerant controller is designed for the NCS.These results are also expanded to the NCS with packet loss and networked-induced delay.Numerical examples are given to illustrate the effectiveness of the proposed design method. 展开更多
关键词 fault tolerant control networked control system (NCS) packet loss actuator fault time delay.
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Fault Tolerant Control for Networked Control Systems with Access Constraints 被引量:4
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作者 ZHAO Ming-Yue LIU He-Ping +2 位作者 LI Zhi-Jun SUN De-Hui LIU Ke-Ping 《自动化学报》 EI CSCD 北大核心 2012年第7期1119-1126,共8页
关键词 网络控制系统 容错控制器 访问限制 Lyapunov函数法 执行器故障 采样时间 设计方法 调度方法
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Fault Estimation and Accommodation for Networked Control Systems with Transfer Delay 被引量:24
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作者 MAO Ze-Hui JIANG Bin 《自动化学报》 EI CSCD 北大核心 2007年第7期738-743,共6页
在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且... 在这份报纸,差错评价和差错的一个方法为有转移延期和进程噪音的联网的控制系统(NCS ) 的容忍的控制被介绍。首先,联网的控制系统作为有转移的分离时间的系统推迟的 multiple-input-multiple-output (MIMO ) 被建模,处理噪音,并且为无常建模。在这个模型下面并且在一些条件下面,一个差错评价方法被建议估计系统差错。根据差错评价和滑动模式控制理论的信息,一个差错容忍的控制器被设计恢复系统性能。最后,模拟结果被用来验证方法的效率。 展开更多
关键词 网络控制系统 迟滞转移 容错估计 容错控制 不确定性模型 滑动模型控制
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Fault detection and accommodation via neural network and variable structure control 被引量:3
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作者 Hao YANG Bin JIANG 《控制理论与应用(英文版)》 EI 2007年第3期253-260,共8页
This paper proposes a novel idea that classifies faults into two different kinds: serious faults and small faults, and treats them with different strategies respectively. A kind of artificial neural network (ANN) i... This paper proposes a novel idea that classifies faults into two different kinds: serious faults and small faults, and treats them with different strategies respectively. A kind of artificial neural network (ANN) is proposed for detecting serious faults, and variable structure (VS) model-following control is constructed for accommodating small faults. The proposed framework takes both advantages of qualitative way and quantitative way of fault detection and accommodation. Moreover, the uncertainty case is investigated and the VS controller is modified. Simulation results of a remotely piloted aircraft with control actuator failures illustrate the performance of the developed algorithm. 展开更多
关键词 fault detection fault accommodation Neural network Variable structure control
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Fault detection and optimization for networked control systems with uncertain time-varying delay 被引量:2
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作者 Qing Wang Zhaolei Wang +1 位作者 Chaoyang Dong Erzhuo Niu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期544-556,共13页
The observer-based robust fault detection filter design and optimization for networked control systems (NOSs) with uncer- tain time-varying delays are addressed. The NCSs with uncertain time-varying delays are model... The observer-based robust fault detection filter design and optimization for networked control systems (NOSs) with uncer- tain time-varying delays are addressed. The NCSs with uncertain time-varying delays are modeled as parameter-uncertain systems by the matrix theory. Based on the model, an observer-based residual generator is constructed and the sufficient condition for the existence of the desired fault detection filter is derived in terms of the linear matrix inequality. Furthermore, a time domain opti- mization approach is proposed to improve the performance of the fault detection system. To prevent the false alarms, a new thresh- old function is established, and the solution of the optimization problem is given by using the singular value decomposition (SVD) of the matrix. A numerical example is provided to illustrate the effectiveness of the proposed approach. 展开更多
关键词 fault detection networked control systems residual generator time-varying delay time domain optimization approach.
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Fault diagnosis of time-delay complex dynamical networks using output signals 被引量:2
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作者 刘昊 宋玉蓉 +1 位作者 樊春霞 蒋国平 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期107-112,共6页
This paper proposes a novel approach for fault diagnosis of a time-delay complex dynamical network. Unlike the other methods, assuming that the dynamics of the network can be described by a linear stochastic model, or... This paper proposes a novel approach for fault diagnosis of a time-delay complex dynamical network. Unlike the other methods, assuming that the dynamics of the network can be described by a linear stochastic model, or using the state variables of nodes in the network to design an adaptive observer, it only uses the output variable of the nodes to design an observer and an adaptive law of topology matrix in the observer of a complex network, leading to simple design of the observer and easy realisation of topology monitoring for the complex networks in real engineering. The proposed scheme can monitor any changes of the topology structure of a time-delay complex network. The effectiveness of this method is successfully demonstrated by virtue of a complex networks with Lorenz model. 展开更多
关键词 time-delay complex dynamical networks fault diagnosis OBSERVER output variable
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Sensor Fault Diagnosis and Reconstruction of Engine Control System Based on Autoassociative Neural Network 被引量:7
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作者 黄向华 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2004年第1期23-27,共5页
The topology and property of Autoassociative Neural Networks(AANN) and theAANN's application to sensor fault diagnosis and reconstruction of engine control system arestudied. The key feature of AANN is feature ext... The topology and property of Autoassociative Neural Networks(AANN) and theAANN's application to sensor fault diagnosis and reconstruction of engine control system arestudied. The key feature of AANN is feature extract and noise filtering. Sensor fault detection isaccomplished by integrating the optimal estimation and fault detection logic. Digital simulationshows that the scheme can detect hard and soft failures of sensors at the absence of models forengines which have performance deteriorate in the service life, and can provide good analyticalredundancy. 展开更多
关键词 autoassociative neural network engine sensor fault diagnosis analyticalredundancy
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Fault Location Identification for Localized Intermittent Connection Problems on CAN Networks 被引量:1
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作者 LEI Yong YUAN Yong SUN Yichao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第5期1038-1046,共9页
The intermittent connection(IC)of the field-bus in networked manufacturing systems is a common but hard troubleshooting network problem,which may result in system level failures or safety issues.However,there is no ... The intermittent connection(IC)of the field-bus in networked manufacturing systems is a common but hard troubleshooting network problem,which may result in system level failures or safety issues.However,there is no online IC location identification method available to detect and locate the position of the problem.To tackle this problem,a novel model based online fault location identification method for localized IC problem is proposed.First,the error event patterns are identified and classified according to different node sources in each error frame.Then generalized zero inflated Poisson process(GZIP)model for each node is established by using time stamped error event sequence.Finally,the location of the IC fault is determined by testing whether the parameters of the fitted stochastic model is statistically significant or not using the confident intervals of the estimated parameters.To illustrate the proposed method,case studies are conducted on a 3-node controller area network(CAN)test-bed,in which IC induced faults are imposed on a network drop cable using computer controlled on-off switches.The experimental results show the parameters of the GZIP model for the problematic node are statistically significant(larger than 0),and the patterns of the confident intervals of the estimated parameters are directly linked to the problematic node,which agrees with the experimental setup.The proposed online IC location identification method can successfully identify the location of the drop cable on which IC faults occurs on the CAN network. 展开更多
关键词 CAN network fault location identification GZIP model intermittent connection
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Kalman filter based fault diagnosis of networked control system with white noise 被引量:5
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作者 YanweiWANG YingZHENG 《控制理论与应用(英文版)》 EI 2005年第1期55-59,共5页
The networked control system NCS is regarded as a sampled control system withoutput time-variant delay. White noise is considered in the model construction of NCS. By using theKalman filter theory to compute the filte... The networked control system NCS is regarded as a sampled control system withoutput time-variant delay. White noise is considered in the model construction of NCS. By using theKalman filter theory to compute the filter parameters, a Kalman filter is constructed for this NCS.By comparing the output of the filter and the practical system, a residual is generated to diagnoseme sensor faults and the actuator faults. Finally, an example is given to show the feasibility ofthe approach. 展开更多
关键词 networked control system fault diagnosis kalman filter
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Fault Detection of Networked Control Systems Based on Optimal Robust Fault Detection Filter 被引量:11
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作者 WANG Yong-Qiang YE Hao +1 位作者 DING X. Steven WANG Gui-Zeng 《自动化学报》 EI CSCD 北大核心 2008年第12期1534-1539,共6页
有可能比一个采样时期大的随机、未知的导致网络的延期的联网的控制系统(NCS ) 的差错察觉在这份报纸被学习。首先,导致网络的延期引起的影响被转变成为错误建模组织,然后存在连续时间域基于引用,模型被扩大到分离时间领域并且适用... 有可能比一个采样时期大的随机、未知的导致网络的延期的联网的控制系统(NCS ) 的差错察觉在这份报纸被学习。首先,导致网络的延期引起的影响被转变成为错误建模组织,然后存在连续时间域基于引用,模型被扩大到分离时间领域并且适用指责联网的控制系统的察觉的柔韧的差错察觉方法。建议方法能被 Matlab LMI 工具箱容易实现,并且它的表演被一个模拟例子最后评估。 展开更多
关键词 检测方法 网络控制系统 最优鲁棒故障检测系统 滤波器
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Fault detection for networked systems subject to access constraints and packet dropouts 被引量:3
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作者 Xiongbo Wan Huajing Fang Sheng Fu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第1期127-134,共8页
This paper addresses the problem of fault detection(FD) for networked systems with access constraints and packet dropouts.Two independent Markov chains are used to describe the sequences of channels which are availa... This paper addresses the problem of fault detection(FD) for networked systems with access constraints and packet dropouts.Two independent Markov chains are used to describe the sequences of channels which are available for communication at an instant and the packet dropout process,respectively.Performance indexes H∞ and H_ are introduced to describe the robustness of residual against external disturbances and sensitivity of residual to faults,respectively.By using a mode-dependent fault detection filter(FDF) as residual generator,the addressed FD problem is converted into an auxiliary filter design problem with the above index constraints.A sufficient condition for the existence of the FDF is derived in terms of certain linear matrix inequalities(LMIs).When these LMIs are feasible,the explicit expression of the desired FDF can also be characterized.A numerical example is exploited to show the usefulness of the proposed results. 展开更多
关键词 fault detection(FD) networked control system(NCS) access constraints packet dropouts linear matrix inequality(LMI).
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Construction of Network Fault Simulation Platform and Event Samples Acquisition Techniques for Event Correlation
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作者 Su Yu-bei Wang Zhi +2 位作者 Cao Yang Huang Tian-xi Wang Li-na 《Wuhan University Journal of Natural Sciences》 EI CAS 2001年第3期670-674,共5页
Event correlation is one key technique in network fault management. For the event sample acquisition problem in event correlation, a novel approach is proposed to collect the samples by constructing network simulation... Event correlation is one key technique in network fault management. For the event sample acquisition problem in event correlation, a novel approach is proposed to collect the samples by constructing network simulation platform. The platform designed can set kinds of network faults according to user's demand and generate a lot of network fault events, which will benefit the research on efficient event correlation techniques. 展开更多
关键词 event correlation network fault simulation event sample
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