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Customized multiwavelets for planetary gearbox fault detection based on vibration sensor signals

Sensors (Switzerland) 2013年第1期13卷 1183-1209页

作者： Sun, Hailiang Zi, Yanyang He, Zhengjia Yuan, Jing Wang, Xiaodong Chen, Lue State Key Laboratory for Manufacturing and Systems Engineering Xi'an Jiaotong University Xi'an 710049 Shaanxi China Shanghai Institute of Radio Equipment Shanghai 200090 China Technology Center CNPC Logging Co. Xi'an 710077 Shaanxi China Beijing Aerospace Control Center Beijing 100094 China

Planetary gearboxes exhibit complicated dynamic responses which are more difficult to detect in vibration signals than fixed-axis gear trains because of the special gear transmission structures. Diverse advanced methods have been developed for this challenging task to reduce or avoid unscheduled breakdown and catastrophic accidents. It is feasible to make fault features distinct by using multiwavelet denoising which depends on the feature separation and the threshold denoising. However, standard and fixed multiwavelets are not suitable for accurate fault feature detections because they are usually independent of the measured signals. To overcome this drawback, a method to construct customized multiwavelets based on the redundant symmetric lifting scheme is proposed in this paper. A novel indicator which combines kurtosis and entropy is applied to select the optimal multiwavelets, because kurtosis is sensitive to sharp impulses and entropy is effective for periodic impulses. The improved neighboring coefficients method is introduced into multiwavelet denoising. The vibration signals of a planetary gearbox from a satellite communication antenna on a measurement ship are captured under various motor speeds. The results show the proposed method could accurately detect the incipient pitting faults on two neighboring teeth in the planetary gearbox. © 2013 by the authors;licensee MDPI, Basel, Switzerland.

关键词： Fault detection

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OPTICAL MEA SUREMENTS OF RAT MUSCLE SAMPLES UND ER TREATMENT WITH ETHYLENE GLYCOL AND GLUCOSE

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Journal of Innovative Optical Health Sciences 2013年第2期6卷 36-50页

作者： LUÍS OLIVEIRA MARIAINÊS CARVALHO ELISABETE NOGUEIRA VALERYV.TUCHIN Physics Department-Polytechnic of Porto School of Engineering Rua Dr.Antònio Bernardino de Almeida4314200-072 PortoPortugal University of Porto Rua Dr.Roberto Frias 4200-465 Porto Portugal CIETI-Centre of Innovationin Engineering and Industrial Technology ISEPRua Dr.Antònio Bernardino de Almeida4314200-072 PortoPortugal DEEC/FEUP and INESC TEC University of Porto Rua Dr.Roberto Frias4200-465 PortoPortugal Research-Educational Institute of Optics and Biophotonics Saratov State University 83 Astrakhanskaya Str.Saratov 410012Russia Laboratory of Laser Diagnostics of Technical and Living Systems Institute of Precise Mechanics and Control RASSaratov 410028Russia Optoelectronics and Measurement Techniques Laboratory P.O.Box 4500 University of OuluFIN-90014OuluFinland

With the objective to study the variation of optical properties of rat muscle during optical clearing,we have performed a set of optical measurements from that kind of *** performed were total tr ansmittance,ollimated transmit tance,specular reflec-tance and total *** set of measurements is suficient to determine diffuse reflectance and absorbance of the sample,also necessary to est imate the optical *** the per formed measurements and calculated quantities will be used later in inverse Monte Carlo(IMC)simu-lations to determine the evolution of the optical properties of muscle during treatments with ethylene glycol and *** results obt ained with the measurements already provide some information about the optical c learing treatments applied to the muscle and translate the mechanisms of turning the tissue more transparent and sequence of regimes of optical clearing.

关键词： Tissue optical clearing optical transmittance optical reflectance optical absorbance agent difusivity

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Parametric Mismatch Detection and Isolation in Model Predictive control System 1

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IFAC Proceedings Volumes 2012年第15期45卷 154-159页

作者： Hong Wang Zhihuan Song Lei Xie State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 Zhejiang China Institute of Cyber-Systems and Control Zhejiang University Hangzhou 310027 Zhejiang China

Predictor that is built from the plant model, plays an important role in model predictive control system. The predictor should be updated timely to maintain certain calculation accuracy and performance optimality. In order to avoid unnecessary interruptions to production, however, updating should only be done when serious mismatch between the process and model appears. A novel method based on subspace approach is proposed to detect the mismatches using closed-loop operation data. The channels with mismatches in multi input multi output system are isolated. And some combinations of the mismatched parameters that have physical significance can be detected. These results provide useful information for the maintenance of model predictive control system. Simulations on a distillation process demonstrate the efficacy of the methodology.

关键词： parametric mismatch model predictive control subspace approach

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Energy optimization analysis of internal thermally coupled air separation columns

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Huagong Xuebao/CIESC Journal 2012年第9期63卷 2936-2940页

作者： Chang, Liang Liu, Xinggao State Key Laboratory of Industrial Control Technology Institute of Industrial Control Zhejiang University Hangzhou 310027 Zhejiang China

Internal thermally coupled distillation column(ITCDIC) is the most promising distillation energy-saving technology. It can save more than 40% energy compared with traditional distillation process, but so far it has not been widely used. The application of the ITCDIC technology in air separation column can bring a good energy saving effect. Based on the characteristic of cryogenic air separation process as well as three-component distillation, a new optimization model of internal thermally coupled air separation columns(ITCASC) is presented. Analysis of energy consumption is carried out detailed. Compared with the conventional air separation columns(CASC), compressor energy consumption decreases by 20.75%, the product value increases by 17.46% and energy consumption per unit of output decreases by 32.53%. The extraction rate and energy consumption of ITCASC are superior to conventional air separation columns. © All Rights Reserved.

关键词： Energy utilization

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Gallager's Error Exponent Analysis of STBC systems over η-μ Fading Channels

Gallager's Error Exponent Analysis of STBC Systems over η-...

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IEEE International Conference on Communications

作者： Jiayi Zhang Michail Matthaiou George K. Karagiannidis Zhenhui Tan Haibo Wang State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China Department of Signals and Systems Chalmers University of Technology Gothenburg Sweden Department of Electrical and Computer Engineering Aristotle University of Thessaloniki Thessaloniki Greece Institute of Broadband Wireless Mobile Communications Beijing Jiaotong University Beijing China

The Gallager's random coding error exponent for space-time block codes (STBC) over multiple-input multiple-output (MIMO) block-fading channels, with Gaussian input distribution, is investigated. Gallager's error exponent can be used to determine the required codeword length to achieve a prescribed error probability at a given rate below the channel capacity. We first provide new, analytical expressions for Gallager's exponent of STBC systems over η-μ fading channels. The Shannon capacity and cutoff rate, which can be directly derived from Gallager's exponent, are further examined. In order to get additional insights, a high signal-to-noise ratio analysis is pursued to investigate the effects of coherence time and codeword length on the error probability. For the sake of completeness, we provide the link to previous known results on Rayleigh and Nakagami-m fading channels.

关键词： MIMO Channel coding Signal to noise ratio Error probability Rayleigh channels

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Multilinear model-based PI control of block-oriented nonlinear systems

Multilinear model-based PI control of block-oriented nonline...

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2011 International Conference on Electrical, Information Engineering and Mechatronics, EIEM 2011

作者： Du, Jingjing Zhang, Xinliang Song, Chunyue School of Electrical Engineering and Automation Henan Polytechnic University Jiaozuo 454000 China State Key Laboratory of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China

ISBN: (纸本)9781447124665

In order to overcome the drawbacks of the conventional nonlinearity inversion control method for block-oriented systems, a Multi-PI control method is proposed. The virtue of the proposed method is that the classic PI control algorithm is applied to complex nonlinear systems, which largely simplifies the control problems and improves control performances. Simulations demonstrate the effectiveness of the proposed Multi-PI control method for block-oriented systems with strong nonlinearity. © 2012 Springer-Verlag London Limited.

关键词： Nonlinear systems

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Prediction error method for identification of LPV models

Prediction error method for identification of LPV models

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作者： Zhao, Yu Huang, Biao Su, Hongye Chu, Jian State Key Lab. of Industrial Control Technology Institute of Cyber Systems and Control Zhejiang University Hangzhou China University of Alberta Department of Chemical and Material Engineering Edmonton AB T6G-2G6 Canada

This paper is concerned with identification of linear parameter varying (LPV) systems in an input-output setting with Box-Jenkins (BJ) model structure. Classical linear time invariant prediction error method (PEM) is extended to the LPV PEM. Under the new LPV framework, identification of two types of input-output LPV models is considered: one is based on parameter interpolation and the other is based on model interpolation. The effectiveness of the proposed solution is validated by comparison with other existing LPV identification approaches through simulation examples and demonstrated by experiment studies. © 2011 Elsevier Ltd. All Rights Reserved.

关键词： Interpolation

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Adaptive observer design for a class of MIMO nonlinear systems

Adaptive observer design for a class of MIMO nonlinear syste...

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World Congress on Intelligent control and Automation (WCICA)

作者： Lili Zhao Xiuliang Li Ping Li State Key Lab of Industrial Control Technology Institute of Industrial Process Control Zhejiang University 310027 China State Key Lab of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University 310027 China

For a class of uniformly observable nonlinear multi-input-multi-output (MIMO) systems with unknown parameters in both state and output equations, an adaptive observer is designed in a constructive manner based on the techniques of high gain observer and adaptive estimation. The high gain adaptive observer for joint state and unknown parameter estimation is conceptually simple. The new algorithm makes use of a time varying gain matrix for unknown parameter estimation, which simplifies the initialization and parameter tuning. In order to establish the global exponential convergence of the adaptive observer, a persistent excitation condition is required. Consequently, the global exponential convergence for simultaneous estimation of states and unknown parameters is formally established following a simple procedure. A numerical example is presented to illustrate the performance of this adaptive observer.

关键词： Equations Observers Adaptive systems Nonlinear systems Symmetric matrices Parameter estimation Mathematical model

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A comparative study of model plant mismatch measures for process monitoring

A comparative study of model plant mismatch measures for pro...

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第23届过程控制会议

作者： Hong Wang Lei Xie Zhihuan Song State Key Laboratory of Industrial Control Technology Institute ofIndustrial Process Control Zheji Institute of Cyber-Systems and Control Zhejiang UniversityHangzhou 310027 Zhejiang China

Model is usually necessary for the design of a control loop. Due to *** and unknown dynamics, model plant mismatch is inevitable in the control loop. In process monitoring, detection of the mismatch and evaluation of its *** are both demanded. In this paper we .rstly present several mismatch measures based on *** model descriptions. Then we categorize them into *** groups from *** perspectives and compare their potential in detection and diagnosis. A case study on a mixing process is presented and some remarks on related aspects are given.

关键词： model plant mismatch process monitoring control loop behavior

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Extremal optimization for unit commitment problem for power systems

Extremal optimization for unit commitment problem for power ...

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IEEE General Meeting Power& Energy Society

作者： Jin Ding Yong-Zai Lu Jian Chu State Key Laboratory of Industrial Control Technology Institute of Cyber-System and Control University of Zhejiang Hangzhou China

This paper introduces extremal optimization (EO) method to solve unit commitment problem for power systems. EO is a local-search heuristic algorithm and originally developed from the fundamentals of statistical physics. In the implementation of EO for unit commitment (UC) problem, a novel problem-specific mutation operator is introduced and rule-based heuristic constraint-repairing techniques are devised. Simulation results on power systems which are composed of up to 100-units over a scheduling horizon of 24-hours demonstrate competitive performance with EO method compared with other existing methods for UC problem.

关键词： Spinning Indexes Power systems Fuels Cost function Power generation

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