非均匀圆柱型正交各向异性圆板的弯曲问题

本文研究了非均匀圆柱型正交各向异性圆板的弯曲问题,求得了折算刚度随半径按指数函数规律变化的非均匀圆柱型正交各向异性圆板在横向均布载荷作用下的通解,并给出了周边固定夹支条件下的精确解。     

关于非均匀圆柱型正交各向异性图板材料性质的研究

在我们已发表的一文中,根据梁的弯曲理论得到了非均匀圆柱型正交各向异性圆板的折算刚度随半径按指数变化的规律.本文的目的在于进一步证明半径对材料性质的影响.按照平面应力一应交关系,我们得到材料性质的数值E_γ,E_θ,ν_θγ是半径γ的函数.我们所得到的解析结果与实验结果是一致的.     

结构动力方程的增维精细积分法

对线性定常结构动力系统提出的精细积分方法,能够得到在数值上逼近于精确解的结果,但对于非齐次动力方程涉及到矩阵求逆的困难。提出采用增维的办法,将非齐次动力方程转化为齐次动力方程,在实施精细积分过程中不必进行矩阵求逆,这种方法对于程序实现和提高数值稳定性十分有利,而且在大型问题中计算效率较高,从而改进了精细积分方法的应用,数值例题显示了本文方法的有效性。     

一类非齐次核的Hilbert型级数算子最佳搭配参数的充要条件

选择搭配参数a,b,利用权函数方法,可得核为K(m,n)的级数算子T的不等式:||T((a))||p,β(a,b) ≤ M(a,b)||(a)||p,α(a,b),(a) ={am}一般地,M(a,b)并不是T:lap(a,b)→lβp(a,b)的算子范数,针对非齐次核K(m,n)=G(mλ1/nλ2)(λ1λ2＞0)...     

Non-homogeneous Dirichlet boundary value problems in weighted Sobolev spaces

The paper presents existence and multiplicity results for non-linear boundary value problems on possibly non-smooth and unbounded domains under possibly non-homogeneous Dirichlet boundary conditions. We develop here an appropriate functional setting based on weighted Sobolev spaces. Our results are obtained by using global minimization and a minimax approach using a non-smooth critical point theory.     

Heat equation with memory in anisotropic and non-homogeneous media

A modified Fourier’s law in an anisotropic and non-homogeneous media results in a heat equation with memory, for which the memory kernel is matrix-valued and spatially dependent. Different conditions on the memory kernel lead to the equation being either a parabolic type or a hyperbolic type. Well-posedness of such a heat equation is established under some general and reasonable conditions. It is shown that the propagation speed for heat pulses could be either infinite or finite, depending on the different types of the memory kernels. Our analysis indicates that, in the framework of linear theory, heat equation with hyperbolic kernel is a more realistic model for the heat conduction, which might be of some interest in physics.     

一类特殊非齐次树上非齐次马尔可夫链的强律

极限定理一直是国际概率论界研究的中心课题之一.本文通过构造适当的辅助非负鞅而给出了一类特殊非齐次树上可列非齐次马尔可夫链场的若干强律.     

非齐型空间上分数型Marcinkiewicz积分算子的加权估计

令（X,d,μ）为满足所谓上倍双倍条件和几何双倍条件的度量测度空间.设M_β,ρ,q为（X,d,μ）上的分数型Marcinkiewicz积分算子.在本文中,作者证明了若β ∈[0,∞）,ρ ∈（0,∞）,q ∈（1,∞）且M_β,ρ,q在L²（μ）上有界,则M_β,ρ,q是从加权Lebesgue空间L^p（w）到加权弱Lebesgue空间L^p,∞（w）上有界和从加权Morrey空间L^p,κ,η（ω）到加权弱Morrey空间WL^p,κ,η（ω）上有界.     

Analysis by electron oscillation in a conventional GC detector

The oscillation of electrons—as driven by AC polarization—can be used to extract a high-sensitivity signal from a conventional electron capture detector. For example, hexachloroethane was detected at a hypercoulometric ratio of 2.0 F/mol, down to ca. 60 fg/s (S/N=3) and with a linear range in excess of two orders of magnitude. The change in carrier gas from nitrogen to argon-methane produced the expected order-of-magnitude increase in optimum oscillation frequency. Anab initio simulation of potentials and ion populations in a heterogeneous electron capture system under a high-frequency AC regime provided further insight into the detector's mechanism: Hypercoulometric response is mainly caused by increased cation-electron recombination in the plasma region, owing to a decreased field gradient and an increased cation concentration.Material taken from doctoral thesis (Dalhousie University, 1987)