首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   77篇
  国内免费   19篇
  完全免费   4篇
  数学   100篇
  2016年   1篇
  2014年   2篇
  2013年   7篇
  2012年   5篇
  2011年   32篇
  2010年   18篇
  2009年   3篇
  2008年   3篇
  2007年   5篇
  2006年   3篇
  2005年   3篇
  2004年   9篇
  2003年   1篇
  2002年   5篇
  2001年   1篇
  2000年   2篇
排序方式: 共有100条查询结果,搜索用时 31 毫秒
1.
The concepts of branching chain in random environmnet and canonical branch-ing chain in random environment are introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment are also given.  相似文献
2.
一类数学生物经济模型的周期性   总被引:4,自引:0,他引:4  
利用重合度理论中的延拓定理研究了一类非自治的数学生物经济模型的正周期解的存在性,得到了保证周期解存在的充分性判据.  相似文献
3.
从p—m链到随机环境中的马氏链   总被引:1,自引:0,他引:1  
第一节引进了p一m链的概念,并用之构造了与它相应的随机环境中的马氏链和绕积马氏链、第二节引进了一系列与随机环境中的马氏链相关的概率特性函数,并得到了这些函数之间的一系列关系.这些结果是经典马氏链的相应结果的一般化,它们在随机环境中的马氏链的极限理论的研究中是很有用的。  相似文献
4.
UMD空间及其应用   总被引:1,自引:0,他引:1  
UMD空间是被广泛研究的一类新型的Banach空间,它具有一系列良好的几何性质与分析性质并且与向量值调和分析、随机分析有着广泛深刻的联系。本扼要介绍这类空间的有关问题,主要是以下几个方面:(1)引言(定义与产生背景);(2)UMD空间的几何特性与分析特征;(3)此类空间的例;(4)在向量值调和分析理论中的应用;(5)关于鞅不等式的最优系数问题。  相似文献
5.
§ 1 Introduction and preliminariesThe equations related to the p- L aplacian operatorΔp have been studied in differentaspects[1— 4 ] sinceΔp arises from a variety of physical phenomena such as non Newtonianfluids,reaction- diffusion problems,etc.In this paper,the following equation(1) which canbe regarded as an extension of those in[1— 4 ]will be discussed:- div(α(gradu) ) +|u(x) |p- 2 u(x) +g(x,u(x) ) =f (x)  a.e. onΩ-〈n,α(gradu)〉∈βx(u(x) ) ,a.e.onΓ . (1)  More details can b…  相似文献
6.
A NOTE ON SINGULAR VALUE DECOMPOSITION FOR RADON TRANSFORM IN R~n   总被引:1,自引:0,他引:1  
The singular value decomposition is derived when the Radon transform is restricted to functions which are square integrable on the unit ball in Rn with respect to the weight Wλ(x). It fulfilles mainly by means of the projection-slice theorem.The range of the Radon transform is spanned by products of Gegenbauer polynomials and spherical harmonics. The inverse transform of the those basis functions are given. This immediately leads to an inversion formula by series expansion and range characterizations.  相似文献
7.
OD-CHARACTERIZATION OF ALMOST SIMPLE GROUPS RELATED TO U6(2)   总被引:1,自引:0,他引:1  
Let G be a finite group and π(G) = { p 1 , p 2 , ··· , p k } be the set of the primes dividing the order of G. We define its prime graph Γ(G) as follows. The vertex set of this graph is π(G), and two distinct vertices p, q are joined by an edge if and only if pq ∈π e (G). In this case, we write p ~ q. For p ∈π(G), put deg(p) := |{ q ∈π(G) | p ~ q }| , which is called the degree of p. We also define D(G) := (deg(p 1 ), deg(p 2 ), ··· , deg(p k )), where p 1 < p 2 < ··· < p k , which is called the degree pattern of G. We say a group G is k-fold OD-characterizable if there exist exactly k non-isomorphic finite groups with the same order and degree pattern as G. Specially, a 1-fold OD-characterizable group is simply called an OD-characterizable group. Let L := U 6 (2). In this article, we classify all finite groups with the same order and degree pattern as an almost simple groups related to L. In fact, we prove that L and L.2 are OD-characterizable, L.3 is 3-fold OD-characterizable, and L.S 3 is 5-fold OD-characterizable.  相似文献
8.
This article deals with a class of numerical methods for retarded differential algebraic systems with time-variable delay. The methods can be viewed as a combination of Runge-Kutta methods and Lagrange interpolation. A new convergence concept, called DA-convergence, is introduced. The DA-convergence result for the methods is derived. At the end, a numerical example is given to verify the computational effectiveness and the theoretical result.  相似文献
9.
Let G=SU(2.2).K=S(U(2)×U(2)),and for l∈Z.let{τ_l}_(leZ) be a one- dimensional K-type and let E_l be the line bundle over G/K associated toτ_l .It is shown thal theτ_l-spher cal function on G is given by the hypergeometric functions of several variables.By applying this result,a central limit theorem for the space G/K is obtained.  相似文献
10.
张勇  赵世舜  董志山 《东北数学》2007,23(6):549-562
In this paper, we discuss the precise asymptotics of moving-average process Xt =∞∑j=0 ajEt-j under some suitable conditions, where {εt, t∈ Z} is a sequence j=0 of stationary ALNQD random variables with mean zeros and finite variances.  相似文献
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号