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Controller Study of DES Petri Net with Uncontrollable Transition

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Controller Study of DES Petri Net with Uncontrollable Transi...

基于强跟踪滤波器的液压伺服系统实时故障诊断

2009中国控制与决策会议

作者： Tao Ze~(1,2),Zhang Hua~1 1.School of Mechanical Engineering,Shenyang Ligong university,Shenyang 110168,china 2.department of automation,tsinghua university,beijing 100084,china

＜正＞A detailed analysis of supervisory control with place and transition hybrid constraints for Petri net based discrete event system with uncontrollable transitions,and a new method for constructing a Petri net feedback controller based on part design and Petri net reduction technique is *** are classified into admissible and inadmissible ***-Transformation method is proposed to transform the inadmissible constraint into admissible one to construct the *** method eases the design of controller and holds remarkable advantages especially for systems with large scale,because it only considers local incident matrix related to the place and transition constraints and uncontrollable ***,the method is proved to be simple and efficient through some examples.

关键词： Petri net controller structural conflict admissible constraint uncontrollable transition

来源： cnki会议评论

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系统仿真学报 2009年第23期21卷 7553-7556页

作者：胡文金周东华重庆科技学院电子信息工程学院重庆401331 清华大学自动化系北京100084

为了在线监测运行工况和提高其可靠性,研究了液压伺服系统的实时故障诊断模型和方法。使用强跟踪滤波器联合估计系统的状态和未知时变参数,使用修正的贝叶斯算法检测故障和估计出故障的幅值,从而建立故障诊断模型和实现液压伺服系统的... 详细信息

为了在线监测运行工况和提高其可靠性,研究了液压伺服系统的实时故障诊断模型和方法。使用强跟踪滤波器联合估计系统的状态和未知时变参数,使用修正的贝叶斯算法检测故障和估计出故障的幅值,从而建立故障诊断模型和实现液压伺服系统的实时故障诊断。仿真结果证实了模型的合理性和可行性,参数估计误差小于1.2%。该方法对模型参数的不确定性具有较强的鲁棒性,能正确检测和分离液压伺服系统的故障。

关键词：液压伺服系统故障诊断强跟踪滤波器参数估计

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降阶奇偶向量在冗余传感器故障检测中的应用

系统仿真学报 2008年第S2期20卷 362-364,397页

作者：高关根程农飞行自动控制研究所西安710065 飞行器控制一体化技术国防重点实验室西安710065 清华大学自动化系北京100084

针对目前大型飞机采用的多套惯性导航系统,提出采用降阶奇偶向量对冗余惯性器件进行元件级故障检测的新方法,该方法不仅可以对单个传感器进行故障的定位与估计,而且可以定位同时出故障的两个传感器,并准确估计故障大小。采用平均奇偶向... 详细信息

针对目前大型飞机采用的多套惯性导航系统,提出采用降阶奇偶向量对冗余惯性器件进行元件级故障检测的新方法,该方法不仅可以对单个传感器进行故障的定位与估计,而且可以定位同时出故障的两个传感器,并准确估计故障大小。采用平均奇偶向量降低噪声对检测效果的影响,可有效检测软故障,降低虚警率。以三套平行放置的惯导系统的陀螺传感器为例,仿真验证该算法的有效性。

关键词：降阶奇偶向量故障检测平均奇偶向量软故障惯性器件

A MESSAGE-DRIVING FORMALISM FOR MODELING AND SIMULATION OF MULTI-AGENT SUPPLY CHAIN SYSTEMS

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 385-399页

作者： Wenzhe TAN1 Yueting CHAI2 Yi LIU3 1department of automation, tsinghua university, beijing, 100084, china 2department of automation, tsinghua university, beijing, 100084, china 3department of automation, tsinghua university, beijing, 100084, china department of automation Tsinghua University Beijing China

To acquire a competitive advantage in the expanding market, manufacturing enterprises should be able to manage their supply chains as effectively as possible. It is now becoming popular to model supply chains as multi-agent systems and use discrete event simulation to learn more about their behaviors or investigate the implications of alternative configurations. In order to enhance the computational efficiency and keep the simulation credibility, this paper proposes a message-driving formalism for the simulation of multi-agent supply chain systems. Through the message-driving formalism, the problem of shared variables is addressed and the parallel operation of agents is implemented. Simulation experiments with a prototype implementation show that the message-driving formalism is able to provide credible results in significantly less simulation time.

关键词： Supply chain multi-agent system modeling and simulation parallel discrete event simulation message-driving formalism

The General Machining Process Simulator GMPS

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Journal of Systems Engineering and Electronics 1994年第3期5卷 73-79页

作者： Xiao Tianyuan, Yang Gang & Li Xin (department of automation, tsinghua university, beijing, china, 100084) department of automation Tsinghua University Beijing China 100084

Automated manufacturing system is characterized by flexibility. It aims at producing a variety of products with virtually no time loses to change over from one part to the next. In this paper, the Machining Process Simulator GMPS is introduced, which can be used as a supported environment for machining process. It can be executed off-line or on-line in manufacturing systems in order to predict the collisions of tool with machined workpieces, fixtures or pallets. First, the functional model of GMPS is described, then adopted critical techniques in the simulator are introduced. Finally, an application of GMPS in CIMS ERC of china is presented.

关键词： Machining process simulator Modeling Front End DNC NC code translator 3D animation detecting collision.

Process data compression based on recursive identification of nonuniformly sampled systems

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控制理论与应用（英文版） 2012年第2期10卷 166-175页

作者： Boyi NI, Deyun XIAO department of automation, tsinghua university, beijing 100084, china department of automation Tsinghua University Beijing China

A recursive identification method is proposed to obtain continuous-time state-space models in systems with nonuniformly sampled （NUS） data. Due to the nonuniform sampling feature, the time interval from one recursion step to the next varies and the parameter is always updated partially at each step. Furthermore, this identification method is applied to form a combined data compression method in NUS processes. The data to be compressed are first classified with respect to a series of potentially existing （possibly time-varying） models, and then modeled by the NUS identification method. The model parameters are stored instead of the identification output data, which makes the first compression. Subsequently, as the second step, the conventional swinging door trending method is carried out on the data from the first step. Numeric results from simulation as well as practical data are given, showing the effectiveness of the proposed identification method and fold increase of compression ratio achieved by the combined data compression method.

关键词： Nonuniformly sampled system Recursive identification Data compression Swinging door trending

SOME PROPERTIES OF LSQR FOR LARGE SPARSE LINEAR LEAST SQUARES PROBLEMS

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Journal of Systems Science & Complexity 2010年第4期23卷 815-821页

作者： Zhongxiao JIA department of Mathematical Sciences,tsinghua university,beijing 100084,china. department of Mathematical Sciences Tsinghua University

It is well-known that many Krylov solvers for linear systems,eigenvalue problems,andsingular value decomposition problems have very simple and elegant formulas for residual *** not only allow us to further understand the methods theoretically but also can be usedas cheap stopping criteria without forming approximate solutions and residuals at each step beforeconvergence takes *** for large sparse linear least squares problems is based on the Lanczosbidiagonalization process and is a Krylov ***,there has not yet been an analogouslyelegant formula for residual *** paper derives such kind of *** addition,the authorgets some other properties of LSQR and its mathematically equivalent CGLS.

关键词： CGLS krylov subspace lanczos bidiagonalization least squares lsqr normal equations.

THE EXISTENCE OF J-HOLOMORPHIC CURVES AND APPLICATIONS TO THE WEINSTEIN CONJECTURE

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Chinese Annals of Mathematics,Series B 1999年第4期20卷 425-434页

作者： MA RENYI(department of Applied Mathmatics, tsinghua university, beijing 100084, china) tsinghua Univ Dept Appl Math Beijing 100084 Peoples R China

The author first proves the existences of J-holomorphic curves in the symplectizations of Legendre fibrations and then as an application confirms the Weinstein conjectures on contact manifolds of Legendre fibrations. As a corollary a new proof on the theorem due to Hofer,Viterbo, Gluck, Ziller, Weinstein and Ljusternik-Fet Theorem is provided, which is quite different from their original proofs.

关键词： Symplectic geometry J-holomorphic curves Periodic orbit

FL-FN-MOGA Based Traffic Signal Control

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Journal of Systems Engineering and Electronics 2003年第3期14卷 14-23页

作者： Wei Wu & Zhang Yi department of automation, tsinghua university, beijing 100084, P. R. china department of automation Tsinghua University Beijing 100084 P. R. China

In this paper, a traffic signal control method based on fuzzy logic (FL), fuzzy-neuro (FN) and multi-objective genetic algorithms (MOGA) for an isolated four-approach intersection with through and left-turning movements is presented. This method has an adaptive signal timing ability, and can make adjustments to signal timing in response to observed *** 'urgency degree' term, which can describe the different user's demand for green time is used in decision-making by which strategy of signal timing can be determined. Using a fuzzy logic controller, we can determine whether to extend or terminate the current signal phase and select the sequences of phases. In this paper, a method based on fuzzy-neuro can be used to predict traffic parameters used in fuzzy logic controller. The feasibility of using a multi-objective genetic algorithm ( MOGA) to find a group of optimizing sets of parameters for fuzzy logic controller depending on different objects is also demonstrated. Simulation results show that the proposed methed is effecfive to adjust the signal timing in response to changing traffic conditions on a real-time basis, and the controller can produce lower vehicle delays and percentage of stopped vehicles than a traffic-actuated controller.

关键词： Traffic signal control Fuzzy logic Fuzzy-neuro Multi-objective genetic algorithms.