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THE STATE SPACE RECONSTRUCTION TECHNOLOGY OF DIFFERENT KINDS OF CHAOTIC DATA OBTAINED FROM DYNAMICAL SYSTEM

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Acta Mechanica Sinica 1999年第1期15卷 82-92页

作者：陈予恕马军海刘曾荣 dept.of mechanics Tianjin UniversityTianjin 300072China Institute of Systems Engineering Southeast UniversityNanjing 210096China dept.of Mathematics Shanghai UniversityShanghai 201800China

Certain deterministic nonlinear systems may show chaotic behavior. We consider the motion of qualitative information and the practicalities of extracting a part from chaotic experimental data. Our approach based on a theorem of Takens draws on the ideas from the generalized theory of information known as singular system analysis. We illustrate this technique by numerical data from the chaotic region of the chaotic experimental data. The method of the singular-value decomposition is used to calculate the eigenvalues of embedding space matrix. The corresponding concrete algorithm to calculate eigenvectors and to obtain the basis of embedding vector space is proposed in this paper. The projection on the orthogonal basis generated by eigenvectors of timeseries data and concrete paradigm are also provided here. Meanwhile the state space reconstruction technology of different kinds of chaotic data obtained from dynamical system has also been discussed in detail.

关键词： nonlinear chaotic data embedding space matrix eigenvalue and eigenvector state space reconstruction

Measurement of refractive index modulation on PMMA/E49/TNF/ECZ polymer-dispersed liquid crystal by fiber F-P interferometer

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Journal of Harbin Institute of Technology(New Series) 2009年第4期16卷 489-491页

作者：韩仁学 dept.of Mathematics and mechanics Heilongjiang Institute of Science and Technology

The fiber Fabry-Perot interferometer used to measure the refractive index modulation of polymer-dispersed liquid crystal is *** measuring the quantity of the interference fringe shift with a CCD based on the theory of isoclinal interference fringes formatting,the maximal refractive index modulation versus different external voltages,3.899×10-3 in the external voltage of 57.4 V/μm,and the dynamic refractive index modulation versus response time in the external voltage of 8 V/μm are found in our prepared 1.250 mm-thick PMMA/E49/TNF/ECZ polymer-dispersed liquid *** experimental results will be helpful to understand the photoinduced reaction mechanism of the material and optimize the mixture ratio of each component.

关键词： refractive index modulation F-P interferometer PMMA/E49/TNF/ECZ

AN IMPROVED CONTACT-IMPACT ALGORITHM FOR EXPLICIT INTEGRATION FEM

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Acta Mechanica Sinica 2002年第6期18卷 649-651页

作者：徐绍忠王乘刘小虎 dept.of mechanics Huazhong Univ. of Sci. and Tech. Wuhan China 430074

Although the penalty algorithm is simple and direct in concept, it has a defect that the contact forces are badly dependent on the chosen penalty factor. An improved contact-impact algorithm for the explicit integration FEM is proposed in the present paper. Based on the fact that bodies cannot penetrate into each other on the contact faces, a set of equations with the additional unknown contact forces on the slave nodes can be formed in a new system configuration. By solving these equations, the correct contact forces could be obtained without using the penalty factor.

关键词： contact-impact algorithm penalty method contact force

NONLINEAR TIME TRANSFORMATION METHOD FOR STRONG NONLINEAR OSCILLATION SYSTEMS

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Acta Mechanica Sinica 1992年第3期8卷 279-288页

作者：徐兆 dept.of mechanics Zhongshan UniversityGuangzhou 510275China

In this paper,a nonlinear time transformation method is presented for the analysis of strong nonlinear oscillation *** method can be used to study the limit cycle behavior of the autonomous systems and to analyze the ... 详细信息

关键词： strong nonlinear oscillation nonlinear time transformation method

PGA and structural dynamics input motion at a given site

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Earthquake Engineering and Engineering Vibration 2003年第1期2卷 25-34页

作者： Fabio Casciati Sara Casciati Alberto Marcellini dept.of Structural mechanics University of Pavia27100 PaviaItaly Professor dept.of Structural mechanics University of Pavia27100 PaviaItaly Ph.D.Student CNR-IDPA 20133 MilanoItaly Research Director

The computation of the representative ground motions,to be used as input for the dynamic analyses of a struc- ture at a particular site,can be approached by several *** choice of the approach depends on two factors:the da- ta available and the type of problem to be *** paper reports the experience of the authors in approaching a specific case study:the Southern Memnon Colossus,located in Luxor,*** results are of interest when the hazard analysis estimation in developing countries and the safeguard of cultural heritage are *** have to be treated as important structures,due to their historical and economical ***,standard procedures of probabilistic seismic haz- ard analysis for the seismic classification of common buildings have to be *** the other hand,the consequences of the collapse of a monument are not comparable to those related to structures such as nuclear power plants and large dams, for which the deterministic seismic hazard analysis provides a straightforward framework for evaluation of the worst case ground ***'intermediate'approach,which requites a lower amount of input data with respect to the deterministic one,is *** stochastic component can eapture significant eharacteristics of earthquakes,primarily the frequency contents which depend on the magnitude(often referred to as the earthquake scaling law).

关键词： accelerograms hazard analysis site effects structural dynamics

Resonance of electromagnetic and mechanic coupling in hydro-generator

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Journal of Harbin Institute of Technology(New Series) 2006年第5期13卷 531-534页

作者：姚大坤邹经湘曲大庄赵树山于开平 dept.of Astronautics and mechanics Harbin Institute of TechnologyHarbin 150001China

Electromagnetic and mechanical forces are main reasons of oscillations in *** oscillation is fairly complicated as to the coupling of *** the method of multiple scales in nonlinear oscillations,instabilities of hydro-generator rotors caused by the unbalanced magnetic pull,which comes from the eccentricity of the rotor,are *** nonlinear properties of the unbalanced magnetic pull,the super-harmonic resonance phenomena are observed as the critical rotating speed of rotors is close to twice of the operating *** is verified by a model experiment,and should be considered during the design of hydro-generator rotors.

关键词： hydro-generator instability coupling resonance

A SURVEY OF WORKS ON THE THEORY OF TOROIDAL SHELLS AND CURVED TUBES

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Acta Mechanica Sinica 1999年第3期15卷 225-234页

作者：任文敏刘文国张维 H.G.Reimerdes H.Oery dept.of Engineering mechanics Tsinghua UniversityBeijing 100084China Institute of Lightstructure RWTH AachenD-52062 AachenGermany

This paper gives a survey of works on the theory of toroidal shells which were done by our two universities in recent years.

关键词： toroidal shells curved tubes

HIGHER ORDER ASYMPTOTIC SOLUTION OF MODE Ⅰ CRACK GROWTH IN ELASTIC-PERFECTLY PLASTIC MEDIA

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Acta Mechanica Sinica 1992年第4期8卷 315-327页

作者：张林黄克智 dept.of Eng.mechanics Tsinghua UniversityBeijing 100084China

A higher order asymptotic solution of near-tip field is studied for plane-atrain Mode-Ⅰ quasi-static steady crack growth in the incompressible (v=1/2) elastic perfectly-plastic *** results show that the near-tip stress and strain are fully continuous,and the strain possesses In (A/r) singularity at the crack *** expressions of the stress,strain and velocity in each region are also given.

关键词： growing crack higher order asymptotic solution near-tip field

Piecewise Linear Analysis for Pseudo-elasticity of Shape Memory Alloy (SMA)

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Journal of Shanghai Jiaotong university(Science) 2005年第1期10卷 48-51页

作者：王晓东杜晓伟孙国钧 dept.of Eng. mechanics Shanghai Jiaotong Univ. Shanghai 200030China

Based on the Brinson constitutive model of SMA, a piecewise linear model for the hysteresis loop of pseudo-elasticity is proposed and applied in the analysis of responses of an SMA-spring-mass system under initial velocity activation. The histories of displacement and velocity of the mass, and the response of stress of SMA are calculated with Brinson’s model and the piecewise linear model. The difference of results of the two models is not significant. The calculation with piecewise-linear model needs no iteration and is highly efficient.

关键词： shape memory alloy(SMA) pseudo-elasticity piecewise linear model Brinson's constitutive law