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1.
In the present paper a finite layer method is studied for the elastodynamics of transverse isotropic bodies. With this method,
semi-infinite soils can be considered as an transverse isotropic half-space, its material functions varying with depth. Dividing
the half-space into a series of layers in the direction of depth, the material functions in each layer are simulated by exponential
functions. Consequently, the fundamental equations to be solved can be simplified if the Fourier transform with repsect to
coordinates is used. We have obtained the relationship between the “layer forces” and “layer displacements”. This finite layer
method, in fact, can also be called a semi-analytical method. It possesses those advantages as the usual semi-analytical methods
do, and can be used to analyse the problem of the interaction between soils and structures.
This paper is based on a portion of the author's dissertation submitted in partial fulfillment of the requirements of degree
of Ph. D. at the Shanghai Institute of Appl. Math. & Mech., Shanghai. 相似文献
2.
In this paper, the differences of turbulent coherent structure between the smooth and rough boundary layers are analysed. Based on the discussing the transient properties from the smooth wall to the rough wall, the physical model of coherent structure for the rough boundary layer are established. The width of slowly-moving turbulent spot and the bursting time are obtained, which are in agreement with experimental results.The project supported by the National Nature Science Foundation of China 相似文献
3.
《Stochastic Processes and their Applications》2020,130(4):2086-2126
4.
In this paper we analyze the behavior of plane harmonic waves and Rayleigh waves in a linear thermoelastic material with voids. We take into account the damped effects of the thermal field upon the propagation waves. Consequently, the propagation condition is established in the form of an algebraic equation of 9th degree whose coefficients are complex numbers while the eigensolutions of the thermoelastodynamic with voids system are explicitly obtained in terms of the characteristic solutions. We show that the transverse waves are undamped in time and they are not influenced by the thermal and porous effects while the longitudinal waves are all damped in time and they are coupled with the thermal and porous effects. The related solution of the Rayleigh surface wave problem is expressed as a linear combination of the eigensolutions in concern. The secular equation is established in an implicit form and afterwards an explicit form is written for an isotropic and homogeneous thermoelastic with voids half-space. Furthermore, we use the numerical methods and computations to solve the secular equation for a specific material. 相似文献
5.
6.
We study the relationship between the Ferrers property and the notion of interval order in the context of valued relations.
Given a crisp preference structure without incomparability, the strict preference relation satisfies the Ferrers property
if and only if the associated weak preference relation does. These conditions characterize a total interval order. For valued
relations the Ferrers property can be written in two different and non-equivalent ways. In this work, we compare these properties
by finding the kind of completeness they imply. Moreover, we study whether they still characterize a valued total interval
orders. 相似文献
7.
Flow through a channel whose walls are lined with non-erodible porous material is investigated using Beavers and Joseph slip
boundary condition. It is shown that the effect of porous lining is to increase the mass flow rate and to decrease the friction
factor. 相似文献
8.
ChaiGenxiang XuKejun 《高校应用数学学报(英文版)》1999,14(3):329-336
In this paper,a semlparametrie resresaion model in which errors are i. i. d random variables from an unknown density f( ) is considered. Based on Hall et al. (1995),a nonlinear wavelet estimation of f( ) without restrictions of continuity everywhere on f( ) is given,and the convergence rate of the estimators in L2 is obtained. 相似文献
9.
We prove the Hölder regularity of bounded weak solutions of doubly nonlinear degenerate parabolic equations with measurable coefficients. 相似文献
10.
Cheng Yanping 《高等学校计算数学学报(英文版)》2000,9(1):71-82
1 IntroductionWeshallconsiderthemodelformiscibledisplacementofonecompressiblefluidbyanotherinahorizontalreservoirΩ R2 ofunitthicknessdescribedbythenonlinearparabolicsystem[6]d(c) p t+ ·u =d(c) p t- · (a(c) p) =q ,(1.1)φ c t+b(c) p t+u· c - · (D(u) c =(^c -c)q ,(1.2 )u·ν =(D(u) c-cu)… 相似文献