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排序方式: 共有2667条查询结果,搜索用时 15 毫秒
111.
We derive asymptotic expansions for tails of infinite weighted convolutions of some heavy-tailed distributions. Applications
are given to tail expansion of the marginal distribution of ARMA processes, randomly stopped sums, as well as limiting waiting
time distribution.
AMS 2000 Subject Classifications. Primary—62E99, Secondary—41A60, 44A35, 60G50, 60K25 相似文献
112.
Jacques Peyriere 《分析论及其应用》2003,19(4):332-341
There are mainly two approaches to the multifractal analysis of measures. The first one, which is used in applications and in studying problems arising from dynamical systems, uses a hierarchy of boxes. The second one, which is more satisfactory from the viewpoint of geometric measure theory, uses more intrinsicconcepts. This article is an account of a work by J. Barral, F. Ben Nasr, and J. Peyriere [3] which pro-vides a bridge between these two theories. 相似文献
113.
A proper subgroup H of a group G is said to be strongly embedded if 2 (H) and 2(HH
g) (for all
). An involution i of G is said to be finite if
(for all g G). As is known, the structure of a (locally) finite group possessing a strongly embedded subgroup is determined by the theorems of Burnside and Brauer--Suzuki, provided that the Sylow 2-subgroup contains a unique involution. In this paper, sufficient conditions for the equality m
2(G)= 1 are established, and two analogs of the Burnside and Brauer—Suzuki theorems for infinite groups G possessing a strongly embedded subgroup and a finite involution are given. 相似文献
114.
It is shown that every probability measure on the interval [0, 1] gives rise
to a unique infinite random graph g on vertices
{v1,
v2, . . .}
and a sequence of random graphs gn on vertices
{v1, . . . ,
vn}
such that
.
In particular,
for Bernoulli graphs with
stable property Q,
can be strengthened to: probability space (, F, P),
set of infinite graphs
G(Q) ,
F with property Q such
that
.AMS Subject Classification: 05C80, 05C62. 相似文献
115.
Wolfgang R.?BergmannEmail author Roberto?ContiEmail author 《Annali di Matematica Pura ed Applicata》2003,182(3):271-286
Let H be the extended Cuntz algebra over the Hilbert space H. Since its zero grade part H0 is the C*-inductive limit of B(Hr), we look for some family of representations on an inductive limit of Hr as r. When such construction is shaped according to the structure of H0, von Neumanns notion of a reference sequence of unit vectors for Hilbert infinite tensor products emerges; after a further Rieffel induction step, a class IPR[H] of representations of H arises. For any two such representations, we describe explicitly their associated intertwiners. Any two representations in IPR[H] are either disjoint or unitarily equivalent. Actions of the group by translation on sequences of unit vectors are involved, as well as the ideals of . 相似文献
116.
区间数的排序方法研究 总被引:27,自引:1,他引:26
指出献^[3-5]所定义的用于区间数排序的可能度存在的不足,分别给出了刻画区间数大小比较的相对优势度的定义和模糊互补矩阵排序的一种新方法。在此基础上,给出了区间数的一种排序方法。 相似文献
117.
Lucio?BoccardoEmail author Luigi?Orsina Alessio?Porretta 《Journal of Evolution Equations》2003,3(3):407-418
This paper deals with existence and regularity results for the problem
$ \cases{u_t-\mathrm{div}(a(x,t,u )\nabla u)=-\mathrm{div}(u\,E)
\qquad in \Omega\times (0,T),\cr u=0 \qquad on \partial \Omega\times (0,T), \cr u (0)= u_0
\qquad in \Omega ,\cr} $
under various assumptions on E and
$ u_0 $. The main difculty in studying this problem is due to the presence of the
term div(uE), which makes the differential operator non coercive
on the "energy space" $ L^2 (0, T; H_0^1 (\Omega)) $.AMS Subject Classification: 35K10, 35K15, 35K65. 相似文献
118.
Norbert Polat 《Czechoslovak Mathematical Journal》2001,51(3):477-492
For an end and a tree T of a graph G we denote respectively by m() and m
T
() the maximum numbers of pairwise disjoint rays of G and T belonging to , and we define tm() := min{m
T(): T is a spanning tree of G}. In this paper we give partial answers — affirmative and negative ones — to the general problem of determining if, for a function f mapping every end of G to a cardinal f() such that tm() f() m(), there exists a spanning tree T of G such that m
T
() = f() for every end of G. 相似文献
119.
A poset (X,) is a split interval order (a.k.a. unit bitolerance order, proper bitolerance order) if a real interval and a distinguished point in that interval can be assigned to each xX so that xy precisely when x's distinguished point precedes y's interval, and x's interval precedes y's distinguished point. For each |X|9, we count the split interval orders and identify all posets that are minimal forbidden posets for split interval orders. The paper is a companion to Counting Split Semiorders by Fishburn and Reeds (this issue). 相似文献
120.
Differences of Convex Compact Sets in the Space of Directed Sets. Part I: The Space of Directed Sets
A normed and partially ordered vector space of so-called directed sets is constructed, in which the convex cone of all nonempty convex compact sets in R
n
is embedded by a positively linear, order preserving and isometric embedding (with respect to a new metric stronger than the Hausdorff metric and equivalent to the Demyanov one). This space is a Banach and a Riesz space for all dimensions and a Banach lattice for n=1. The directed sets in R
n
are parametrized by normal directions and defined recursively with respect to the dimension n by the help of a support function and directed supporting faces of lower dimension prescribing the boundary. The operations (addition, subtraction, scalar multiplication) are defined by acting separately on the support function and recursively on the directed supporting faces. Generalized intervals introduced by Kaucher form the basis of this recursive approach. Visualizations of directed sets will be presented in the second part of the paper. 相似文献