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1.
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   
2.
The problem of estimation of the heavy tail index is revisited from the point of view of truncated estimation. A class of novel estimators is introduced having guaranteed accuracy based on a sample of fixed size. The performance of these estimators is quantified both theoretically and in simulations over a host of relevant examples. It is also shown that in several cases the proposed estimators attain — within a logarithmic factor — the optimal parametric rate of convergence. The property of uniform asymptotic normality of the proposed estimators is established.  相似文献   
3.
群G的一个子群H称为在G中S-拟正规嵌入的,如果对H阶中的每一个素因子p,H的Sylowp-子群也是G的某个S-拟正规子群的Sylowp-子群.利用子群的S-拟正规嵌入性给出了群为p-幂零群及超可解群的一些特征.  相似文献   
4.
借助实例分析的方法,讨论在证明微分与积分相结合的中值定理类命题时,关于辅助函数的构造技巧及其变形思想.  相似文献   
5.
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   
6.
特殊半鞅的一个局部性质   总被引:1,自引:1,他引:0  
本文讨论特殊半鞅的一个局部性质,将局部(平方可积)鞅的结果推广到了一类特殊半鞅的情形。  相似文献   
7.
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   
8.
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.
本文给出SL2(C)中具有两个生成元的可解子群的结构定理,并由单值群的可解性定义一类环面T2上Fuchs系统的可积性,进而研究该系统的解的一些大范围性质.  相似文献   
10.
一类非线性二阶差分方程解的振动性   总被引:7,自引:0,他引:7  
本文建立了非线性二阶差分方程的若干振动准则,所得结果改进了文[5]中相应的定理.  相似文献   
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