共查询到20条相似文献,搜索用时 265 毫秒
1.
带强迫项高阶中立型微分方程的振动性和非振动性 总被引:1,自引:0,他引:1
我们给出一类强迫高阶非线性中立型时滞微分方程一切解振动的充分条件.而且,也研究了一类强迫一阶中立型方程非振动解的渐近性. 相似文献
2.
3.
中立型泛函微分方程解的振动性 总被引:2,自引:1,他引:1
近来,中立型泛函微分方程解的振动性已引起许多作者的注意:如阮炯,毛士忠等,Grammatikopoulos et.al.,Sticas et.al.,Grove et.al.和G.Ladas et.al.中立型泛函微分方程解的振动性的研究虽有许多困难,但由于滞后型和超前型方程解的振动性的研究的不断深入使我们对一大类中立型方程解的振动性的研究成为可能. 相似文献
4.
研究了一类二阶非线性摄动微分方程解的振动性质和渐近性质,建立了两个新的振动性与渐近性定理,推广和改进了已有的一些结果. 相似文献
5.
本文考虑一类非线性延迟微分方程-带有单调造血率的造血模型数值解的振动性.通过研究特征方程根的情况得到数值解振动的条件并且讨论了非振动的数值解的一些性质.为了更有力的说明我们的结果,最后给出了相应的算例. 相似文献
6.
本文研究二阶非线性中立型方程(2)非振动解的渐近性和存在性.当 0(?)sum from i=1 to mc_i(t)<1时,(2)最多有 S(0,0,0),S(b,a,0),S(∞,∞,0)和 S(∞,∞,d)四种类型的非振动解.我们给出了各种类型非振动解存在的充分条件或充分必要条件. 相似文献
7.
二阶非线性中立型方程非振动解的渐近性和存在性 总被引:3,自引:0,他引:3
本文研究二阶非线性中立型方程(2)非振动解的渐近性和存在性.当 0(?)sum from i=1 to mc_i(t)<1时,(2)最多有 S(0,0,0),S(b,a,0),S(∞,∞,0)和 S(∞,∞,d)四种类型的非振动解.我们给出了各种类型非振动解存在的充分条件或充分必要条件. 相似文献
8.
在α>1,且0<β<α情性下研究了高阶具非线性中立项不稳定型时滞微分方程[x(t)-pxα(t-τ)](n)=q(t)xβ(t-σ),(t≥t0)的振动和非振动性.利用一些新的技巧,获得了上述方程有界解振动的振动准则和至少存在一个非振动解的非振动准则,所得结果补充和推广了已有文献部分结果. 相似文献
9.
研究了一类二阶非线性摄动微分方程解的振动性与渐近性,建立了四个新的振动性与渐近性定理,推广和改进了已知的一些结果. 相似文献
10.
n 阶非线性时滞微分方程的振动性与渐近性 总被引:25,自引:0,他引:25
在本文中,我们研究了具有强迫项的n阶非线性时滞微分方程的振动性与渐近性.建立了某些充分条件,在这些条件下,如果 n 为偶数,方程的所有解为振动的;而 n 为奇数,方程的所有解或者振动,或者解本身及它的 1 至 n-1 阶导数都单调趋于零. 相似文献
11.
Jogi Henna 《Annals of the Institute of Statistical Mathematics》2005,57(4):655-664
An estimator of the number of components of a finite mixture ofk-dimensional distributions is given on the basis of a one-dimensional independent random sample obtained by a transformation
of ak-dimensional independent random sample. A consistency of the estimator is shown. Some simulation results are given in a case
of finite mixtures of two-dimensional normal distributions. 相似文献
12.
有资格限制的指派问题的求解方法 总被引:3,自引:0,他引:3
在实际的指派工作中,常会遇到某个人有没有资格去承担某项工作的问题,因此,本建立了有资格限制的指派问题的数学模型。在此数学模型中,将效益矩阵转化为判定矩阵,由此给出了判定此种指派问题是否有解的方法;在有解的情况下,进一步将效益矩阵转化为求解矩阵,从而将有资格限制的指派问题化为传统的指派问题来求解。最后给出了一个数值例子来说明这样的处理方法是有效的。 相似文献
13.
We study the nilpotency of the sums of all coefficients of some sorts of products of polynomials over reversible, IFP, and NI rings, and introduce an SCN ring as a generalization. We characterize SCN rings in relation with related ring properties, and also provide several useful properties and ring extensions of SCN rings. 相似文献
14.
N/Kbe a Galois extension of number fields with finite Galois group G.We describe a new approach for constructing invariants of the G-module structure of the K groups of the ring of integers of N in the Grothendieck group of finitely generated projective Z[G]modules. In various cases we can relate these classes, and their function field counterparts, to the root number class of Fröhlich and Cassou-Noguès. 相似文献
15.
Piotr Je¸drzejewicz 《代数通讯》2013,41(4):1500-1508
Let A be a UFD of characteristic p > 0, let 𝒵 be a set of some eigenvectors of a derivation of A. We prove, under some additional assumptions, a necessary and sufficient condition for 𝒵 to be a p-basis of the minimal ring of constants containing 𝒵. The main preparatory result is the unique decomposition theorem with respect to a factor from a given subalgebra containing Ap. 相似文献
16.
本文在LF拓扑空间中建立了L-fuzzy集网的弱收敛(R-收敛)概念,应用文[4]中的R-闭包,系统讨论了它们的性质,证明了等式RlimA_n=∧(∨A_m)_R和RlimA_n=A_n=∧(∨A_m)_R并且给出了L-fuzzy集网与其子网之间的关系。 相似文献
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This note deals with the R-order of convergence of Weierstrass-Durand-Kerner-Dochev type single-step methods for the simultaneous determination of only a part of all roots of algebraic polynomials. 相似文献
19.
Imme P. van den Berg 《Logic and Analysis》2008,1(2):153-185
One method to determine the asymptotics of particular solutions of a difference equation is by solving an associated asymptotic
functional equation. Here we study the behaviour of the solutions in an asymptotic neighbourhood of such individual solutions.
We identify several types of attraction and repulsion, which range from almost orthogonality to almost parallelness. Necessary
and sufficient conditions for these types of behaviour are given. 相似文献
20.
Let L be the Euclidean functional with p-th power-weighted edges. Examples include the sum of the p-th power-weighted lengths of the edges in minimal spanning trees, traveling salesman tours, and minimal matchings. Motivated
by the works of Steele, Redmond and Yukich (Ann. Appl. Probab. 4, 1057–1073, 1994, Stoch. Process. Appl. 61, 289–304, 1996) have shown that for n i.i.d. sample points {X
1,…,X
n
} from [0,1]
d
, L({X
1,…,X
n
})/n
(d−p)/d
converges a.s. to a finite constant. Here we bound the rate of convergence of EL({X
1,…,X
n
})/n
(d−p)/d
.
Y. Koo supported by the BK21 project of the Department of Mathematics, Sungkyunkwan University.
S. Lee supported by the BK21 project of the Department of Mathematics, Yonsei University. 相似文献