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1.
陈目 《大学数学》2007,23(4):66-72
利用积分平均技巧,得到了半线性二阶阻尼微分方程[a(t)|x′(t)|α-1x′(t)]′+p(t)k(t,x(t),x′(t))x′(t)+q(t)|x(t)|α-1x(t)=0的一些新的振动定理.这些结果改进和推广了Manojlovic J V[5]的结果.  相似文献   

2.
该文主要研究了二阶中立型Emden-Fowler微分方程(r(t)|z′(t)|~(α-1)z′(t))′+p(t)|z′(t)|~(α-1)z′(t)+q(t)|x(σ(t))|~(β-1)x(σ(t)=0的振动性,其中z(t)=x(t)+g(t)x(τ(t)).利用广义Riccati变换和积分平均技巧建立新的振动准则,推广和改进了一些文献中的结果.  相似文献   

3.
本文研究下列n阶RFDE边值问题:x(n)(t)=f(t,xt,x(t),x′(t),…,x(n-1)(t)), t∈[0,T ],x(t)=φ(t),t∈[-r,0];x′(0)=η,x″(0)=η2,…,x(n-2) (0)=ηn-2,x(j)(T)=A,其中j∈I={0,1,2,…,n-1},得到了解的存在性和唯一性新的结果.  相似文献   

4.
In this paper we study the oscillation of the retarded differential equation x′(t)+∫abp(t,ξ)x[g(t,ξ)]dσ(ξ)=0 (b>a) (1)and the advanced differential equation x′(t)-∫abp(t,ξ)x[g(t,ξ)]dσ(ξ)=0 (b>a) (2) We improved the main results of [1-4].  相似文献   

5.
研究了二阶中立型广义Emden-Fowler方程(r(t)|z′(t)|~(α-1)z′(t))′+f(t,x[σ(t)])=0,t≥t_0的若干新的振动准则,其中z(t)=x(t)+p(t)x(τ(t)),f(t,x)sgnx≥q(t)|x|~β,α0,β0为实数,结果改进、推广和统一了最近文献中的一些熟知的结果,为证明我们结果的重要性,也给出了若干说明的例子.  相似文献   

6.
建立了中立型Emden-Fowler泛函微分方程(r(t)z′(t)|~(α-1)z′(t))′+q(t)|x(δ(t))|~(β-1)x(δ(t))=0,t≥t_0的若干新的振动准则,其中z(t)=x(t)+p(t)x(τ(t)),α0,β0为常数.所得的结果推广和改进了近期文献的某些熟知的结果.  相似文献   

7.
建立了Emden-Fowler型泛函微分方程(r(t)|z′(t)|~(α-)z′(t))′+q(t)f(x(σ(t)))=0,t≥t_0.的若干新的振动准则,其中α0,z(t)=x(t)+p(t)x(τ(t)).结果改进和推广了最近文献的一些熟知的结果,并且给出了说明所得结果的重要性的一些例子.  相似文献   

8.
张静  陈目 《大学数学》2011,27(3):124-130
对一类二阶Emden-Fowler型中立型时滞积分方程(a(t)x′(t))′+q<,1>(t)|y(t-σ<,1>)|<'α>sgn x(t-σ<,1>)+g<,2>(t)|y(t-σ<,2>)|<'β>sgn y(t-σ<,2>)=0,利用Riccati技巧和积分平均法,给出了一些判定其解振动的充分判据.这些判据仅...  相似文献   

9.
本文研究了—类带有阻尼项的二阶半线性中立型微分方程(r(t)φ(x(t))|(x(t)+p(t)x(σ(t)))′|α-1(x(t)+p(t)x(σ(t))′)′+φ(x(t),x′(t)+q0(t)|x(Τ0(t))|α-1x(Τ0(t))+nΣi=1qi(t)|x(Τi(t))|βi-1x(Τi(t))=0的解的性质,其中n是—个偶数,利用一些新的技巧,我们获得了方程解的振动的一些充分条件,并且给出例子阐述我们所得的结论.  相似文献   

10.
设{W(t),t≥0}是一标准Wiener过程,记S是Strassen重对数律的紧集类·本文中我们讨论了两个变量sup0≤t≤1-h inff∈S sup0≤x≤1 |(W(t+hx)-W(t))(2h log h-1)-1/2 - f(x)|及inf0≤t≤1-h sup0≤x≤1 |(W(t + hx) - W(t))(2hlogh-1)-1/2- f(x)|(对任何f∈S)趋于零的精确的收敛速度.作为一个推广,我们建立了Wiener过程的不可微模与泛函的连续模之间的一种关系.  相似文献   

11.
12.
Schr(o)dinger operator is a central subject in the mathematical study of quantum mechanics.Consider the Schrodinger operator H = -△ V on R, where △ = d2/dx2 and the potential function V is real valued. In Fourier analysis, it is well-known that a square integrable function admits an expansion with exponentials as eigenfunctions of -△. A natural conjecture is that an L2 function admits a similar expansion in terms of "eigenfunctions" of H, a perturbation of the Laplacian (see [7], Ch. Ⅺ and the notes), under certain condition on V.  相似文献   

13.
14.
正Applied Mathematics-A Journal of Chinese Universities,Series B(Appl.Math.J.Chinese Univ.,Ser.B)is a comprehensive applied mathematics journal jointly sponsored by Zhejiang University,China Society for Industrial and Applied Mathematics,and Springer-Verlag.It is a quarterly journal with  相似文献   

15.
正Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.  相似文献   

16.
A cumulative-capacitated transportation problem is studied. The supply nodes and demand nodes are each chains. Shipments from a supply node to a demand node are possible only if the pair lies in a sublattice, or equivalently, in a staircase disjoint union of rectangles, of the product of the two chains. There are (lattice) superadditive upper bounds on the cumulative flows in all leading subrectangles of each rectangle. It is shown that there is a greatest cumulative flow formed by the natural generalization of the South-West Corner Rule that respects cumulative-flow capacities; it has maximum reward when the rewards are (lattice) superadditive; it is integer if the supplies, demands and capacities are integer; and it can be calculated myopically in linear time. The result is specialized to earlier work of Hoeffding (1940), Fréchet (1951), Lorentz (1953), Hoffman (1963) and Barnes and Hoffman (1985). Applications are given to extreme constrained bivariate distributions, optimal distribution with limited one-way product substitution and, generalizing results of Derman and Klein (1958), optimal sales with age-dependent rewards and capacities.To our friend, Philip Wolfe, with admiration and affection, on the occasion of his 65th birthday.Research was supported respectively by the IBM T.J. Watson and IBM Almaden Research Centers and is a minor revision of the IBM Research Report [6].  相似文献   

17.
Résumé On décrit toutes les feuilles des laminations minimales dont un ensemble résiduel de feuilles ont 2 bouts.   相似文献   

18.
We develop a theory of downward sets for a class of normed ordered spaces. We study best approximation in a normed ordered space X by elements of downward sets, and give necessary and sufficient conditions for any element of best approximation by a closed downward subset of X. We also characterize strictly downward subsets of X, and prove that a downward subset of X is strictly downward if and only if each its boundary point is Chebyshev. The results obtained are used for examination of some Chebyshev pairs (W,x), where ∈ X and W is a closed downward subset of X  相似文献   

19.
In this paper, the author establishes the boundedness of multilinear operators on weighted Herz spaces and Herz-type Hardy spaces. The author also obtains their weak estimates on endpoints. As a special case, the conclusions may lead to the weighted estimates for multilinear Calderon-Zygmund operators.  相似文献   

20.
In this paper we present a generalized quantitative version of a result due to M. Revers concerning the exact convergence rate at zero of Lagrange interpolation polynomial to f(x) = |x|α with on equally spaced nodes in [-1, 1].  相似文献   

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