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1.
该文建立了广义中立型Emden-Fowler方程(r(t)|y′(t)|~(α-1)y′(t))′+f(t,x(σ(t)))=0,t≥t_0的若干新的振动准则,其中α0,y(t)=x(t)+p(t)x(7-(t)),-μ≤p(t)≤1,μ∈(0,1).所得的结果改进和推广了最近文献中的一些结果.也给出了说明所得结果的重要性的例子.  相似文献   

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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   

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李晓迪 《应用数学》2008,21(2):404-410
考虑下列二阶脉冲微分系统解的振动性{(r(t))(x′(t)σ)′ a(t)(x([t]))δ e(t)sgn x(t)=0,t≠n,t≥0,n∈Z ,x(n)=gn(x(n-)),x′(n)=hn(x′(n-)),t=n,n=1,2,…,其中s,d是任意给定的正奇数的商.借助脉冲微分不等式得到了保证上述系统所有有界解振动的若干充分条件,并给出例子说明定理的应用.  相似文献   

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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   

5.
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   

6.
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   

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研究了如下一维p-Laplace方程Neumann边值问题(φp(u′(t)))′=f(t,u(t),u′(t)),t∈(0,1),u′(0)=u′(1)=0,解的存在性,这里φp(s)=|s|p-2s.通过使用上下解方法和度理论,获得了边值问题解的存在性结果.  相似文献   

8.
确定了一类中心循环的有限p-群G的自同构群.设G=X_3(p~m)~(*n)*Z_(p~(m+r)),其中m≥1,n≥1和r≥0,并且X_3(p~m)=x,y|x~(p~m)=y~(p~m)=1,[x,y]~(p~m)=1,[x,[x,y]]=[y,[x,y]]=1.Aut_nG表示Aut G中平凡地作用在N上的元素形成的正规子群,其中G'≤N≤ζG,|N|=p~(m+s),0≤s≤r,则(i)如果p是一个奇素数,那么AutG/Aut_nG≌Z_(p~((m+s-1)(p-1))),Aut_nG/InnG≌Sp(2n,Z_(p~m))×Z_(p~(r-s)).(ii)如果p=2,那么AutG/Aut_nG≌H,其中H=1(当m+s=1时)或者Z_(2~(m+s-2))×Z_2(当m+s≥2时).进一步地,Aut_nG/InnG≌K×L,其中K=Sp(2n,Z_(2~m))(当r0时)或者O(2n,Z_(2~m))(当r=0时),L=Z_(2~(r-1))×Z_2(当m=1,s=0,r≥1时)或者Z_(2~(r-s)).  相似文献   

9.
该文建立了广义中立型Emden.Fowler方程(r(t)|z'(t)|~(α-1)z'(t))'+q(t)|x(σ(t))|~(β-1)x(σ(t))=0的若干新的振动准则,其中z(t)=x(t)+p(t)x(τ-(t)),α0,β0,所得结果改进和推广了最近文献中的一些结果.  相似文献   

10.
关于Littlewood的一个问题   总被引:1,自引:0,他引:1  
本文证明了: (1)如果{a_n}_n~N=1是非负不减序列,p>0,q>0,0≤r≤1,且p(q+r)≥q+p,则sum from n=1 to N(a_n~pA_n~q)(sum from m=n to N(a_n~(1+p/q)~r≤1·sum from n=1 to N(a_n~pA_n~q)~(1+p/q),其中A_n=sum from m=n to n (a_m).上述不等式在0≤r≤1时完全解决了H.Alzer~([4])在1996年提出的一个问题,且1是最佳常数; (2)如果{a_n}_n~N=1是非负序列,p,p≥1,r>0,r(p-1)≤2(q-1),令α=((p-1)(q+r)+p~2+1)/(p+1) β=(2p+2r+p-1)/(q+1),σ=(q+r-1)/(p+q+r)则sum from n=1 to N (a_n~p)sum from i=1 to n (a_i~qA_i~r)≤2~σsum from n=1 to N(a_n~αA_n~β)(0.2)(0.2)式改进了G.Be(?)et~([2,3])在1987年对Littlewood一个问题的结果,常数因子的3/2降为2~(3/2)=1.2598…  相似文献   

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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.
We study a class of self-similar processes with stationary increments belonging to higher order Wiener chaoses which are similar to Hermite processes. We obtain an almost sure wavelet-like expansion of these processes. This allows us to compute the pointwise and local Hölder regularity of sample paths and to analyse their behaviour at infinity. We also provide some results on the Hausdorff dimension of the range and graphs of multidimensional anisotropic self-similar processes with stationary increments defined by multiple Wiener–Itô integrals.  相似文献   

14.
It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary.  相似文献   

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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   

17.
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   

18.
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   

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