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1.
Florentina Chirte§ 《Central European Journal of Mathematics》2005,3(1):105-124
The aim of this paper is to define the localization LM
n
-algebra of an LM
n
—algebra L with respect to a topology F on L; in Section 5 we prove that the maximal LM
n
-algebra of fractions (defined in [3]) and the LM
n
-algebra of fractions relative to an Λ—closed system (defined in Section 2) are LM
n
-algebras of localization. 相似文献
2.
Zhijian Qiu 《Integral Equations and Operator Theory》2007,59(2):223-244
Let K be a compact subset in the complex plane and let A(K) be the uniform closure of the functions continuous on K and analytic on K°. Let μ be a positive finite measure with its support contained in K. For 1 ≤ q < ∞, let Aq(K, μ) denote the closure of A(K) in Lq(μ). The aim of this work is to study the structure of the space Aq(K, μ). We seek a necessary and sufficient condition on K so that a Thomson-type structure theorem for Aq(K, μ) can be established. Our theorem deduces J. Thomson’s structure theorem for Pq(μ), the closure of polynomials in Lq(μ), as the special case when K is a closed disk containing the support of μ. 相似文献
3.
In [1], we defined c(G), q(G) and p(G). In this paper we will show that if G is a p-group, where p is an odd prime and |G| ≤ p
4, then c(G) = q(G) = p(G). However, the question of whether or not there is a p-group G with strict inequality c(G) = q(G) < p(G) is still open. 相似文献
4.
R. M. Mnatsakanov N. Misra Sh. Li E. J. Harner 《Mathematical Methods of Statistics》2008,17(3):261-277
For estimating the entropy of an absolutely continuous multivariate distribution, we propose nonparametric estimators based
on the Euclidean distances between the n sample points and their k
n
-nearest neighbors, where {k
n
: n = 1, 2, …} is a sequence of positive integers varying with n. The proposed estimators are shown to be asymptotically unbiased and consistent.
相似文献
5.
An f-coloring of a graph G is an edge-coloring of G such that each color appears at each vertex v V(G) at most f(v) times. The minimum number of colors needed to f-color G is called the f-chromatic index of G and is denoted by X′f(G). Any simple graph G has the f-chromatic index equal to △f(G) or △f(G) + 1, where △f(G) =max v V(G){[d(v)/f(v)]}. If X′f(G) = △f(G), then G is of f-class 1; otherwise G is of f-class 2. In this paper, a class of graphs of f-class 1 are obtained by a constructive proof. As a result, f-colorings of these graphs with △f(G) colors are given. 相似文献
6.
Emrah Kilic 《Proceedings Mathematical Sciences》2008,118(1):27-41
In this paper, we consider generalized Fibonacci type second order linear recurrence {u
n
}. We derive a generating matrix for both the sums of squares, ∑
i=0
n
u
i
2 and the products of the form u
n
u
n+2. We also derive explicit formulas for the sums and products by using matrix methods. Then we give a matrix method to generate
the sums of product of two consecutive terms u
n
u
n+1 as well as the product, u
n
u
n+2. Further we give generating functions and combinatorial representations of the sums of squares of terms of {u
n
} and the product, u
n
u
n+2. 相似文献
7.
Hanno Lefmann 《Discrete and Computational Geometry》2008,40(3):401-413
We consider a variant of Heilbronn’s triangle problem by investigating for a fixed dimension d≥2 and for integers k≥2 with k≤d distributions of n points in the d-dimensional unit cube [0,1]
d
, such that the minimum volume of the simplices, which are determined by (k+1) of these n points is as large as possible. Denoting by Δ
k,d
(n), the supremum of this minimum volume over all distributions of n points in [0,1]
d
, we show that c
k,d
⋅(log n)1/(d−k+1)/n
k/(d−k+1)≤Δ
k,d
(n)≤c
k,d
′/n
k/d
for fixed 2≤k≤d, and, moreover, for odd integers k≥1, we show the upper bound Δ
k,d
(n)≤c
k,d
″/n
k/d+(k−1)/(2d(d−1)), where c
k,d
,c
k,d
′,c
k,d
″>0 are constants.
A preliminary version of this paper appeared in COCOON ’05. 相似文献
8.
Namir Ghoraf 《TOP》2008,16(1):62-72
An “m-consecutive-k-out-of-n:F system” consists of n components ordered on a line; the system fails if and only if there are at least m nonoverlapping runs of k consecutive failed components. In this paper, we give a recursive formula to compute the reliability of such a system. Thereafter,
we state two asymptotic results concerning the failure time Z
n
of the system. The first result concerns a limit theorem for Z
n
when the failure times of components are not necessarily with identical failure distributions. In the second one, we prove
that, for an arbitrary common failure distribution of components, the limit system failure distribution is always of the Poisson
class.
相似文献
9.
V. K. Maslyuchenko V. V. Mykhailyuk O. I. Filipchuk 《Ukrainian Mathematical Journal》2008,60(11):1803-1812
We introduce the notion of categorical cliquish mapping and show that, for each K
h
C-mapping f: X × Y → Z, where X is a topological space, Y is a space with the first axiom of countability, and Z is a Moore space, with categorical-cliquish horizontal y-sections f
y
, the sets C
y
(f) are residual G
δ-type sets in X for every y ∈ Y.
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 60, No. 11, pp. 1539–1547, November, 2008. 相似文献
10.
Soltan 《Discrete and Computational Geometry》2003,29(4):561-573
Abstract. Generalizing the characteristic intersection property of Choquet simplices, it is proved that for line-free convex bodies
B
1
and B
2
in E
d
, the following conditions are equivalent: (i) there is a line-free convex body B ⊂ E
d
such that every nonempty intersection B
1
∩ (v + B
2
) , v ∈ E
d
, is a homothetic copy of B , (ii) both B
1
and B
2
are Choquet simplices and the nonempty intersections B
1
∩ (v + B
2
) , v ∈ E
d
, are homothetic copies of a Choquet simplex B . All such triplets B
1
,B
2
,B are described. 相似文献
11.
12.
Xiao Yun CHENG Jian Guo XIA Hou Rong QIN 《数学学报(英文版)》2007,23(5):819-826
Let K2 be the Milnor functor and let Фn (x)∈ Q[X] be the n-th cyclotomic polynomial. Let Gn(Q) denote a subset consisting of elements of the form {a, Фn(a)}, where a ∈ Q^* and {, } denotes the Steinberg symbol in K2Q. J. Browkin proved that Gn(Q) is a subgroup of K2Q if n = 1,2, 3, 4 or 6 and conjectured that Gn(Q) is not a group for any other values of n. This conjecture was confirmed for n =2^T 3S or n = p^r, where p ≥ 5 is a prime number such that h(Q(ζp)) is not divisible by p. In this paper we confirm the conjecture for some n, where n is not of the above forms, more precisely, for n = 15, 21,33, 35, 60 or 105. 相似文献
13.
If (N,t) ({\cal N},\tau) is a finite von Neumann algebra and if (M,n) ({\cal M},\nu) is an infinite von Neumann algebra, then Lp(M,n) L_{p}({\cal M},\nu) does not Banach embed in Lp(N,t) L_{p}({\cal N},\tau) for all p ? (0,1) p\in (0,1) . We also characterize subspaces of $ L_{p}({\cal N},\tau),\ 0< p <1 $ L_{p}({\cal N},\tau),\ 0< p <1 containing a copy of lp. 相似文献
14.
Let Λ be a finitely generated associative k-algebra where k is an algebraically closed field. For each natural number d, we have the variety of d-dimensional module structures on kd given by the multiplication of the elements from a generating set of Λ. The general linear group Gld(k) acts on this variety by conjugation and the orbits under this action correspond to isomorphism classes of d-dimensional Λ-modules. For two d-dimensional Λ-modules M and N one says that M degenerates to N if the orbit corresponding to N is in the Zariski-closure of the orbit corresponding to M. Now in this situation the stabilizers of the elements in the orbit corresponding to N acts on the orbit corresponding to M.
In this paper we characterize degenerations of k[t]/(tr)-modules with the property that for each y in the orbit corresponding to N, there is an xy in the orbit corresponding to M such that the orbit corresponding to M is the disjoint union of orbits of the xy’s under the action of the stabilizer of y where y runs through the orbit corresponding to N.
Presented by Idun ReitenMathematics Subject Classifications (2000) 14L30, 16G10. 相似文献
15.
Eiichi Nakai 《数学学报(英文版)》2008,24(8):1243-1268
Let X = (X, d,μ) The purpose of this paper is to be a space of homogeneous type in the sense of Coifman and Weiss. generalize the definition of Hardy space H^P(X) and prove that the generalized Hardy spaces have the same property as H^P(X). Our definition includes a kind of Hardy- Orlicz spaces and a kind of Hardy spaces with variable exponent. The results are new even for the R^n case. Let (X, δ, μ) be the normalized space of (X, d, μ) in the sense of Macias and Segovia. We also study the relations of our function spaces for (X, d, μ) and (X, δ,μ). 相似文献
16.
Manoj K. Yadav 《Proceedings Mathematical Sciences》2008,118(1):1-11
We give a sufficient condition on a finite p-group G of nilpotency class 2 so that Aut
c
(G) = Inn(G), where Aut
c
(G) and Inn(G) denote the group of all class preserving automorphisms and inner automorphisms of G respectively. Next we prove that if G and H are two isoclinic finite groups (in the sense of P. Hall), then Aut
c
(G) ≃ Aut
c
(H). Finally we study class preserving automorphisms of groups of order p
5, p an odd prime and prove that Aut
c
(G) = Inn(G) for all the groups G of order p
5 except two isoclinism families. 相似文献
17.
Bao Qin Li 《Mathematische Zeitschrift》2008,258(4):763-771
We show that meromorphic solutions f, g of f
2 + g
2 = 1 in C2 must be constant, if f
z2 and g
z1 have the same zeros (counting multiplicities). We also apply the result to characterize meromorphic solutions of certain
nonlinear partial differential equations. 相似文献
18.
Let G = ℤ
p
, p an odd prime, act freely on a finite-dimensional CW-complex X with mod p cohomology isomorphic to that of a lens space L
2m−1(p; q
1, …, q
m
). In this paper, we determine the mod p cohomology ring of the orbit space X/G, when p
2 ∤ m. 相似文献
19.
V. V. Shchigolev 《Journal of Mathematical Sciences》2007,142(2):2015-2019
In this paper, we calculate the space Ext
GL(n
1
)(L
n
(λ), L
n
(μ)), where GL(n) is the general linear group of degree n over an algebraically closed field of positive characteristic, L
n
(λ) and L
n
(μ) are rational irreducible GL(n)-modules with highest weights λ and μ, respectively, the restriction of L
n
(λ) to any Levi subgroup of GL(n) is semisimple, λ is a p-restricted weight, and μ does not strictly dominate λ.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 2, pp. 219–226, 2005. 相似文献
20.
Shui-Li Chen Guo-Long Chen Jian-Cheng Zhang 《Fuzzy Optimization and Decision Making》2008,7(4):351-360
In this paper, an ω-convergence theory of filters in an Lω-space is established. By means of the ω-convergence theory, some important characterizations with respective to the ω-closed sets, ω
T
2 separation and (ω
1, ω
2)-continuous mappings are obtained. Moreover, the mutual relationships among ω-convergence of molecular nets, ω-convergence of ideals and ω-convergence of filters are given. 相似文献