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991.
992.
Summary Exact stationary solutions are constructed for nonlinear dynamic systems subjected to stochastic excitation. The results are then applied to both classical and nonclassical stochastic vibration systems. 相似文献
993.
杨守志 《应用数学和力学(英文版)》2006,27(12):1687-1695
Poly-scale refinable function with dilation factor a is introduced. The existence of solution of poly-scale refinable equation is investigated. Specially, necessary and sufficient conditions for the orthonormality of solution functionφof poly-scale refinable equation with integer dilation factor a are established. Some properties of poly-scale re-finable function are discussed. Several examples illustrating how to use the method to construct poly-scale refinable function are given. 相似文献
994.
We propose a new approach for the discretization of diffusive flux on a non orthogonal mesh based on the Deferred correction introduced by Peric. This new method is applied successfully to the solution of a Poisson problem in quadrangular domains meshed with very distorted control volumes. The interest of this approach lies in the fact that the precision of the used schemes is conserved despite meshes distortion level. The comparative study of the value of the spectral radius of iteration matrix enables us to explain why our Deferred correction approach is better than that of Peric, which diverges on highly skewed meshes. To cite this article: Y.M. Ahipo, Ph. Traore, C. R. Mecanique 334 (2006). 相似文献
995.
The problem of the diffraction of surface waves, obliquely incident on a partially immersed fixed vertical barrier in deep water, is solved approximately by reducing it to the solution of an integral equation, for small angle of incidence of the incident wave. The corrections to the reflection and transmission coefficients over their normal incidence values for small angle of incidence are obtained and presented graphically for some intermediate values of wave numbers. 相似文献
996.
997.
Based on the complex viscosity model various steady-state and transient material functions have been completed. The model is investigated in terms of a corotational frame reference. Also, BKZ-type integral constitutive equations have been studied. Some relations between material functions have been derived.
C
–1
Finger tensor
-
F[], (F
–1[])
Fourier (inverse) transform
-
rate of deformation tensor in corotating frame
-
h(I, II)
Wagner's damping function
-
J
(x)
Bessel function
-
m
parameter inh (I, II)
-
m(s)
memory function
-
m
k, nk
integers (powers in complex viscosity model)
-
P
principal value of the integral
-
parameter in the complex viscosity model
-
rate of deformation tensor
-
shear rates
-
[], []
incomplete gamma function
-
(a)
gamma function
-
steady-shear viscosity
-
*
complex viscosity
-
,
real and imaginary parts of
*
-
0
zero shear viscosity
-
+,
1
+
stress growth functions
-
–,
1
-
stress relaxation functions
-
(s)
relaxation modulus
-
1(s)
primary normal-stress coefficient
-
ø(a, b; z)
degenerate hypergeometric function
-
1, 2
time constants (parameters of
*)
-
frequency
-
extra stress tensor 相似文献
998.
Experimental observations show that quasi-isotropic materials, such as N-axial fibre-reinforced composites and woven materials, exhibit various degrees of anisotropy in elasticity and strength, and the anisotropy in strength is normally stronger than that in elasticity. In view of some available experimental data and based on the general formulation of the constitutive equations and failure criteria of quasi-isotropic materials established by using the theory of representations for tensor functions, we postulate several applicable models of the constitutive equations and strength for 3-and 4-axial quasi-isotropic materials to reveal the anisotropic effects. In a continued work (Part II), the anisotropic effect in strength of an infinitely large plate with a single elliptical hole or crack is studied, and the proposed stiffness and strength models are verified in terms of micro-mechanical analyses.Project supported by the National Natural Science Foundation of China and the State Education Commission Foundation of China 相似文献
999.
We suggest a new method for studying finite dimensional dynamics for evolutionary differential equations. We illustrate this
method for the case of the KdV equation. As a side result we give constructive solutions of the boundary problem for the Schrodinger
equations whose potentials are solutions of stationary KdV equations and their higher generalizations. 相似文献
1000.
王向东 《应用数学和力学(英文版)》1998,(6)
I.IntroductionLetFbethen-dimensionalEuclideanspaceandGaboundeddomaininM,WI(C)andM(C)beusualSobolevspaces.Let0相似文献