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Modelling of gear stochastic vibration.considering non-white noise errors

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Chinese Science Bulletin 1999年第4期44卷 375-378页

作者： Yong Wang Wenjun Zhang City Univ Hong Kong Dept Mfg Engn Hong Kong Hong Kong

A model to simulate the non-Gaussian non-white-noise random errors of gears is developed with the influence of rotational speed considered. The gear transmission errors is first decomposed into harmonic and random components based on the spectral analysis. Then, a second-order Markov process with time-variant parameters is used to simulate the non-Gaussian non-white-noise random component of gears. The second-order Markov process is used as a shaping filter. The input of the filter is a white Gaussian noise process, and the output is the random erros of gears. Furthermore, a new dynamic and stochastic simulation model for the rotational bivration of gear transmission system is proposed. The influences of the random errors on vibration.acceleration are examined by use of the developed simulation system.

关键词： gear random error Markov process stochastic vibration.

Studies on Infrared Spectra of High-Temperature Superconductors~*

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Science China Mathematics 1993年第12期36卷 1489-1500页

作者：曾文生张光寅李增发阎少林熊光诚王守证 Department of Physics Zhongshan University Department of Physics Nankai University Department of Electronic Science Nankai University Department of Physics Peking University

The anisotropic behaviour of high-temperature superconductors in their infrared spectra is reported systematically for the first time. A theoretical description is given. Based on the studies on the infrared spectra of the samples which are Y-system single crystal films, Y-system compounds annealed at different quenching temperatures and the Prdoped Y-system single phase compounds, the systematical assignments of infrared phononsof these high temperature superconducting compounds are made. It is proposed that the lattice vibration. in the CuO2 plane have a close relation with the high temperature superconductivity. The role of these vibration. in superconductivity is discussed further.

关键词： high-temperature superconductivity infrared spectroscopy anisotropic property lattice vibration.

Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science China Earth Sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2, TENG Jiwen2, LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. Institute of Intelligent Instrument & Measurement Control Technology, Jilin University, Changchun 130026, China 2. Institute of Geology & Geophysics, Chinese Academy of Sciences, Beijing 100029, China Institute of Intelligent Instrument & Measurement Control Technology Jilin University Changchun China Institute of Geology & Geophysics Chinese Academy of Sciences Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration.analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

FORCED SOLITARY WAVES IN A PARAMETRICALLY EXCITED CIRCULAR TANK

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Science China Mathematics 1992年第5期35卷 570-575页

作者：王本仁 ROBERT.E.APFEL Institute of Acoustics Nanjing University Nanjing 210008 PRC Yale University Connecticut 06520 U.S.A.

A new mode of nonpropagating solitary waves in circular tank, which are forcedly ex-cited in tbe vertical direction, is described. The waveform is measured and the data accordwell with the hyperbolic secant *** of the vibration.modes of the wave showthat the mode is not a pure mode of circular container. A wax cone was inserted in themiddle of tank in order to keep down the plateau. The hysteresis phenomenon of excitation ofsolitary wave has been observed as well.

关键词： solitary wave water waves nonpropagating solitary wave parametrically excited vibration.

Decentralized adaptive generalized predictive control for structural vibration

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Progress in Natural Science:Materials International 2005年第3期 75-80页

作者： LU Minyue and GU Zhongquan ˇ (National Key Laboratory of Rotorcraft Aeromechanics,Nanjing University of Aeronautics and Astronautics,Nanjing210016,China) National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A decentralized generalized predictive control(GPC)algorithm is developed for strongly coupled multi-input multi-out-put systems with parallel *** algorithm is applied to adaptive control of structural *** key steps in this algorithm are to group the actuators and the sensors and then to pair these groups into *** is important that the on-line identification and the control law design can be a parallel process for all these *** avoids the high computation cost in ordinary predictive control,and is of great advantage especially for large-scale systems.

关键词： adaptive control predictive control decentralized control vibration.

A MODEL FOR FLEXURAL vibration.OF LAMINATED BEAMS EMBEDDED WITH PIEZOELECTRIC LAYERS INCLUDING SHEAR DEFORMATION

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A MODEL FOR FLEXURAL VIBRATION OF LAMINATED BEAMS EMBEDDED W...

Random Response of Linear Viscoelastic Systems under Random Excitation

2006年中国机械工程学会年会暨中国工程院机械与运载工...

作者： WANG Yun*, XU Rongqiao *College of Electromechanical Engineering, Hangzhou Dianzi University, Hangzhou 310018, China. Department of Civil Engineering, Zhejiang University, Hangzhou 310027, China

A beam embedded piezoelectric layers is widely used as actuator to excite or control the vibration. of machines and structures. It is also applied as sensor to measure vibration.. By using the hypothe

关键词： Piezoelectric layer laminated beam vibration.

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Journal of Donghua University(English Edition) 2001年第1期18卷 68-71页

作者： Zhang Tianshu(张天舒) Fang Tong(方同) Department of Basic Science Dong Hua University Shanghai 200051 Department of Engineering Mechanics Northwestern Polytechnical University Xi''an 710072

A method of analyzing random response of linear viscoelastic systems under random excitation has been presented. The covariance matrices of random responses of a single-degree-freedom linear viscoelastic system subjected to stationary white noise and filtered white noise excitations have been obtained in closed form. For illustration, a numerical example has been included. It is observed that viscoelasticity has damping effect on the mean square random responses of the system, the higher is viscoelastic behavior, the higher the damping effect.

关键词： Random response, Viscoelastic system, Random vibration.

Localization of Distributed Fiber Sensor Employing a Sub-Ring

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Journal of Electronic Science and Technology of China 2008年第4期6卷 377-380页

作者： Wei-Min Chen Yuan-Yuan Xie Peng Zhang Lei Lin School of Optical Electronical Engineering Chongqing University Chongqing 400044China School of Computer Science and InformationEngineering Chongqing Technology and Business University Chongqing400067 China

A simple distributed optical fiber sensing system used to monitor vibration.signal has an additional sub-loop eoupled with main ring by a 3 dB coupler. This paper compares three outputting interfered beams, each of them travels in the sub-ring 0, 1, 2 times, separately. Using the simultaneous equations produced by those three outputs, we find the relation between the interference lights and vibration.signal＇s characteristics, such as frequency, amplitude and position. Through simplifying and calculating, the vibration.position can be obtained finally.

关键词： Distributed fiber interference,localization sensor vibration.

BEHAVIOUR OF STEEL-SOIL BRIDGE MADE OF CORRUGATED PLATES UNDER DYNAMIC TESTS

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BEHAVIOUR OF STEEL-SOIL BRIDGE MADE OF CORRUGATED PLATES UND...