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101.
R. Grzhibovskis S. Rjasanow H. Andrä A. Zemitis 《Mathematical Methods in the Applied Sciences》2010,33(8):1021-1034
A boundary integral formulation of the linear elasticity problem for a multi‐component composite is given. The fast BEM solver based on the adaptive cross approximation is then obtained by the data‐sparse representation of the resulting Galerkin matrices. The solver is used to obtain effective elastic moduli of fibre and particle reinforced composites in three dimensions by means of the strain energy equivalence principle. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
102.
103.
YCESAN Ahmet~ KEN A.Ceylan Department of Mathematics Süleyman Demirel University Isparta Turkey 《中国科学A辑(英文版)》2008,51(2):233-240
We derive intrinsic formulation for elastic line deformed on a pseudo-hypersurface by an external field in the pseudo-Euclidean spaces E_v~n.This formulation determines elastic line deformed on a pseudo-hypersurface. 相似文献
104.
We give a new proof of Kolodner's result that longitudinal waves can propagate in at least three directions in a hyperelastic
anisotropic medium. We give examples of an orthotropic hyperelastic tensor with exactly three such directions, of a monoclinic
elastic (but not hyperelastic) tensor with only one, and of a monoclinic elastic (elliptic, but not uniformly elliptic) tensor
with no direction for longitudinal waves.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
105.
Based on the Floquet theory on ordinary differential equations with periodically variable coefficients and the bifurcation
approach to nonlinear equations, a numerical approach to determining the stability region of control parameters is established
for a dynamic control system composed of a moving body levitated magnetically over flexible guideways. The system is nonlinearly
coupled among the elastic deformation of guideways, disturbance the levitation position of the body and electromagnetic control
forces. The numerical simulation is given for the system in the case in which the control parameters are taken within and
out of the stability region respectively. Results show that this approach is reliable.
This project is supported by NSFC(No. 19725207), the Pre-research Project of the Committee of Science and Technology for Defence
of China and the Science Foundation of Education Ministry of China for Ph. D. Programmes. 相似文献
106.
107.
108.
HUANG Jianguo SHI Zhongci & XU Yifeng Department of Mathematics Shanghai Jiaotong University Shanghai China Division of Computational Science E-lnstitute of Shanghai Universities Shanghai Normal University China Institute of Computational Mathematics Academy of Mathematics System Sciences Chinese Academy of Sciences Beijing China 《中国科学A辑(英文版)》2005,48(7):986-1007
The aim of this paper is to study the static problem about a general elastic multi-structure composed of an arbitrary number of elastic bodies, plates and rods. The mathematical model is derived by the variational principle and the principle of virtual work in a vector way. The unique solvability of the resulting problem is proved by the Lax-Milgram lemma after the presentation of a generalized Korn's inequality on general elastic multi-structures. The equilibrium equations are obtained rigorously by only assuming some reasonable regularity of the solution. An important identity is also given which is essential in the finite element analysis for the problem. 相似文献
109.
Analysis results for the elastic properties of a composite with a small amount of coplanarly arranged platelike filler particles
are presented. The geometrical form of the particles is described by an oblate ellipsoid of revolution. The calculations are
performed by formulas obtained by using the Eshelby approach for media with a low concentration of inclusions. The effect
of anisometry of the ellipsoidal particles and of the ratio between the elastic moduli of the filler and matrix on the effective
elastic constants of the composite is discussed. Calculation results are compared with experimental data for the elastic moduli
of a nanocomposite containing completely exfoliated particles of an unmodified montmorillonite.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 44, No. 4, pp. 493–504, July–August, 2008. 相似文献
110.
LU Juan ZHOU Li-Huan MA Wei-Xing HE Xiao-Rong 《理论物理通讯》2008,49(1):207-211
Based on the quark-gluon structure of nucleon and the existence of Odderon in nucleon via gluon selfinteraction, the elastic scattering of pp at high energies is studied. Our theoretical predictions reproduce experimental data perfectly. The contributions from individual terms of quark-quark, gluon-gluon interactions, quark-gluon interference and the Odderon terms to total cross section are analyzed. In addition to the leading quark-quark contribution, the Odderon contribution is quite important. In particular, the Odderon plays an essential role in fitting to data. Therefore, We may claim that the high energy pp and pp elastic scattering may be good processes to search for the Odderon, the three Reggeized gluon bound states. 相似文献