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Fault prediction model based on evidential reasoning approach

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Science china(Information Sciences) 2010年第10期53卷 2032-2046页

作者： SI XiaoSheng 1,2 , HU ChangHua 1 & zhou ZhiJie 1,2 1 Unit 302, Xi’an Institute of Hi-Tech, Shaanxi, Xi’an 710025, china 2 department of automation, tsinghua university, beijing 100084, china 1. Unit 302 Xi’an Institute of Hi-Tech Shaanxi Xi’an 710025 China2. Department of Automation Tsinghua University Beijing 100084 China

In order to deal with fault prediction problems that involve both quantitative and qualitative in-formation for nonlinear complex system, a new fault prediction model is established based on the evidential reasoning (Er) approach, and an optimal learning algorithm for training Er-based prediction model is pre-sented based on the mean square error (MSE) criterion. This prediction model inherits the advantages of Er approach, which can deal with precise data, incomplete data and fuzzy data with nonlinear characteristic. In this model, the input signals transformed using rule based information transformation technique, are aggregated by analytical Er approach, and then the outputs of prediction model are constructed according to the types of system outputs. In addition, two fault decision criteria are defined to conduct fault identification. To overcome the difficulty in determining model parameters accurately and subjectively, a nonlinear optimization model is constructed and the optimal parameters are obtained. Two experimental studies are conducted to evaluate the performance of the proposed model. The results show that the established prediction model and the presented parameters optimization methods can deal with fault prediction problem effectively.

关键词： fault prediction evidential reasoning belief distribution nonlinear optimization

Truncation error calculation based on richardson extrapolation for variable-step collaborative simulation

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Science china(Information Sciences) 2011年第6期54卷 1238-1250页

作者： ZHANG HeMing 1 , liang SiLu 2 , SONG ShiJi 1 & WANG HongWei 3 1.department of automation, tnlist, tsinghua university, beijing 100084, china 2 Computer and Information Management Center, tsinghua university beijing 100084, china 3 Engineering Design Centre, Engineering department, Cambridge university, Cambridge CB2 1pZ, UK 1. department of automation TNList Tsinghua University Beijing 100084 China2. Computer and Information Management Center Tsinghua University Beijing 100084 China3. Engineering Design Centre Engineering Department Cambridge University Cambridge CB2 1PZ UK

Collaborative simulation is an effective approach to performing simulation analysis for complex systems by integrating models developed for different engineering disciplines. Collaborative simulation issues include the modeling of coupled multidisciplinary systems, and the simulation running time integration of these models that are solved parallelly. Estimation of the local truncation error of coupling models is the key to solve multidisciplinary collaborative simulation problem, which is actually used to restrict the simulation step. This paper presents a variable-step method based on richardson extrapolation for calculating the local truncation error to solve collaborative simulation problem of multidisciplinary coupling models. Formulas for estimating the local truncation error are derived through theoretical analysis by using integration methods and interpolation technologies, respectively. The simulation experiments are illustrated to validate the accuracy and efficiency of proposed collaborative simulation algorithm in comparison with the usual combinative algorithm.

关键词： multidisciplinary systems collaborative simulation variable-step algorithm error estimation

real-time reliability prediction for dynamic systems with both deteriorating and unreliable components

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Science in china(Series F) 2009年第11期52卷 2234-2246页

作者： XU ZhengGuo1,2, JI YinDong2,3 & zhou DongHua1,2? 1.department of automation, tsinghua university, beijing 100084, china 2 tsinghua National Laboratory for Information Science and Technology, tsinghua university, beijing 100084, china 3 research Institute of Information Technology (rIIT), tsinghua university, beijing 100084, china department of automation Tsinghua University Beijing 100084 China tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100084 China research Institute of Information Technology (rIIT) Tsinghua University Beijing 100084 China

As an important technology for predictive maintenance, failure prognosis has attracted more and more attentions in recent years. real-time reliability prediction is one effective solution to failure prognosis. Considering a dynamic system that is composed of normal, deteriorating and unreliable components, this paper proposes an integrated approach to perform real-time reliability prediction for such a class of systems. For a deteriorating component, the degradation is modeled by a time-varying fault process which is a linear or approximately linear function of time. The behavior of an unreliable component is described by a random variable which has two possible values corresponding to the operating and malfunction conditions of this component. The whole proposed approach contains three algorithms. A modified interacting multiple model particle filter is adopted to estimate the dynamic system＇s state variables and the unmeasurable time-varying fault. An exponential smoothing algorithm named the Holt＇s method is used to predict the fault process. In the end, the system＇s reliability is predicted in real time by use of the Monte Carlo strategy. The proposed approach can effectively predict the impending failure of a dynamic system, which is verified by computer simulations based on a three-vessel water tank system.

关键词： reliability failure prognostics dynamic systems fault prediction particle filtering interacting multiple model exponential smoothing,predictive maintenance

维普期刊数据库

A new DSmT combination rule in open frame of discernment and its application

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Science china(Information Sciences) 2012年第3期55卷 551-557页

作者： WEN ChengLin1, XU XiaoBin1,2 , JIANG HaiNa1 & zhou Zhe1 1School of automation, Hangzhou DianZi university, Hangzhou 310018, china 2department of automation and tsinghua National Laboratory for Information Science and Technology, tsinghua university, beijing 100049, china 1. School of automation Hangzhou DianZi University Hangzhou 310018 China2. Department of Automation and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100049 China

A new combination rule based on Dezert-Smarandache theory (DSmT) is proposed to deal with the conflict evidence resulting from the non-exhaustivity of the discernment frame. A two-dimensional measure factor in Dempster-Shafer theory (DST) is extended to DSmT to judge the conflict degree between evidence. The original DSmT combination rule or new DSmT combination rule can be selected for fusion according to this degree. Finally, some examples in simultaneous fault diagnosis of motor rotor are given to illustrate the effectiveness of the proposed combination rule.

关键词： DSmT rule of combination open frame of discernment evidence conflict simultaneous faults diagnosis generalized basic probability assignment

A revisit to the Stability of Spatially Interconnected Systems

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A Revisit to the Stability of Spatially Interconnected Syste...

第二十九届中国控制会议

作者： zhou tong department of automation and tnlist,tsinghua university,beijing 100084,p.r.china

A necessary and sufficient condition is derived in this paper for the stability of a linear time invariant（LTI）multidimen-sional（MD）dynamic *** condition is expressed by a set of linear matrix inequalities（LMIs）.A special characteristic of this condition is that although the number of LMIs increases exponentially with the spatial dimension of the system,the dimensions of the LMIs are identical to each other and are of the same order as those of system ***,both the number and the dimensions of the LMIs are explicitly *** properties make the derived condition particularly attractive when the spatial dimensions are low that are frequently encountered in practical applications.

关键词： Linear Matrix Inequality Multidimensional System Multi-input Multi-output System Stability Spatio-Temporal System

Direct regulation Estimation of Cellular Networks with Time Series and Steady State Data

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Direct Regulation Estimation of Cellular Networks with Time ...

第三十届中国控制会议

作者： WANG Yali~1,zhou tong~(1,2) 1.department of automation,tsinghua university,beijing 100084,p.r.china 2.tsinghua National Laboratory for Information Science and Technology(tnlist),tsinghua university,beijing 100084,p.r.china

One of the main aims in systems biology is to gain knowledge about direct regulation effects among numerous cellular *** this paper,two algorithms are proposed to estimate direct causal regulations from noisy time series experimental *** incorporating a so-called power law which is an important network structural characteristic of most large scale cellular networks,a likelihood function is developed and minimized by three *** essential step is determining which chemical elements have direct regulation effects on a prescribed element,when the number of direct regulations is known. To avoid the inherent combinatorial computation problem,two procedures are proposed yo give analytical solutions about the positions of these *** addition,the possibility of integrating information of time series and steady state data into network inferences is also investigated in this paper,and finally two improved algorithms are developed based on these two kinds of data. These algorithms have been applied to many artificially constructed networks with 101 *** with total least squares(TLS) method,which is widely used in noisy measurement data case,numerical simulations show that,the false positive errors can be significantly reduced and estimation accuracy can be extremely ***,the performances of improved algorithms are greatly better than the time series data based algorithms.

关键词： Direct regulation Cellular Network power Law Maximum Likelihood Estimation

Stability Analysis for Spatially Distributed Dynamic Systems

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Stability Analysis for Spatially Distributed Dynamic Systems

第二十六届中国控制会议

作者： zhou tong department of automation,tsinghua university,beijing 100084,p.r.china

In this paper,a sufficient condition is derived for the stability of a spatially invariant distributed dynamical （SIDD） system,based on the geometrical structure of the null space of a matrix *** condition is less conservative than the available computationally feasible ***,using the idea of parameter dependent linear matrix inequalities （LMI）,a necessary and sufficient condition is *** of these two conditions are expressed by LMIs,and can therefore in principle be computationally *** the necessity of the latter condition is lost if the degree of the related multivariate matrix polynomials is small,its conservatism can be sequentially reduced through increasing this degree step by step.

关键词： Linear matrix inequality Multivariate matrix polynomial parameter dependent LMI Spatially distributed dynamic system Stability.

An Optimal Driving Strategy for High-Speed Electric Train

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An Optimal Driving Strategy for High-Speed Electric Train

第三十届中国控制会议

作者： LI liang~(1,2),DONG Wei~2,JI Yindong~2,ZHANG Zengke~1 1.department of automation,tsinghua university,beijing 100084,p.r.china 2.National Laboratory for Information Science and Technology,tsinghua university,beijing 100084,p.r.china

＜正＞In this paper we investigate the minimum-energy driving problem for high-speed electric train,and propose a three- stage optimal *** firstly introduce the switching systems model to describe the new dynamics in high-speed electric train,which considers the extended range of speed,the energy efficiency and the regenerative *** on the new model, we then study the optimal driving strategy with minimum energy consumption,and the problem boils down to optimal control for switching *** a numerical algorithm,we get a three-stage driving strategy,in which the traditional quasi-coasting stage is discarded and the maximum traction and brake are not suitable *** last,a case study on CrH is illustrated.

关键词： Optimal Driving Minimum Energy High-Speed Electric Train Switching Systems

FrEQUENCY rESpONSE ESTIMATION FOr NOrMALISED COprIME FACTOrS—THE MIMO SYSTEM CASE"

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FREQUENCY RESPONSE ESTIMATION FOR NORMALISED COPRIME FACTORS...

第二十三届中国控制会议

作者： tong zhou department of automation, tsinghua university, beijing, 100084

＜正＞ This paper extends to multi-input multi-output （A1IMO） systems the results on frequency response estimation for normalised coprime factors （NCF） from closed-loop frequency domain experimental data. An analytic solution has been obtained for the maximum likelihood estimate （MLE） on the basis of a linear fractional transformation （LFT） representation for all the plant possible normalised right coprime factors （NrCF）. It is proved that the estimate can be expressed by a linear combination of a normalised random matrix with all its columns having independent complex normal distributions. Some methods are suggested to reduce the estimation bias when high quality experimental data are available.

关键词： closed-loop identification maximum likelihood estimate MIMO system normalised coprime factorization robust control.