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1.
Alberto Saracco 《Bulletin des Sciences Mathématiques》2008,132(3):232
We deal with the cohomology of semi 1-coronae. Semi 1-coronae are domains whose boundary is the union of a Levi flat part, a 1-pseudoconvex part and a 1-pseudoconcave part. Using the main result in [C. Laurent-Thiébaut, J. Leiterer, Uniform estimates for the Cauchy-Riemann equation on q-concave wedges, in: Colloque d'Analyse Complexe et Géométrie, Marseille, 1992, Astérisque 217 (7) (1993) 151-182], we prove a bump lemma for compact semi 1-coronae in Cn and then, applying Andreotti-Grauert theory, we get a cohomology finiteness theorem for coherent sheaves whose depth is at least 3. As an application we get an extension theorem for coherent sheaves and analytic subsets. 相似文献
2.
Giuseppe Tomassini 《Milan Journal of Mathematics》2007,75(1):399-412
We deal with the general problem of extension of analytic objects in a complex space X. After a short presentation of the classical results we discuss some recent developments obtained when X is a semi-1-corona. Semi-1-coronae are domains C
+ whose boundary is the union of a Levi flat part, a 1-pseudoconvex part and a 1-pseudoconcave part. Using the main result
in [31], we prove a “bump lemma” for compact semi-1-coronae in and then, applying Andreotti-Grauert theory, we get a cohomology finiteness theorem for coherent sheaves whose depth is at
least 3. As an application we get an extension theorem for coherent sheaves and analytic subsets.
Received: April 2007 相似文献
3.
Yaroslav Kopylov 《Archiv der Mathematik》2007,89(1):87-96
We consider some problems concerning the L
p,q
-cohomology of Riemannian manifolds. In the first part, we study the question of the normal solvability of the operator of
exterior derivation on a surface of revolution M considered as an unbounded linear operator acting from Lpk (M) into Lk+1q (M). In the second part, we prove that the first L
p,q-cohomology of the general Heisenberg group is nontrivial, provided that p < q.
Received: 17 January 2006
Supported by INTAS (Grant 03–51–3251) and the State Maintenance Program for the Leading Scientific Schools of the Russian
Federation (Grants NSh 311.2003.1, NSh 8526.2006.1). 相似文献
4.
A set of vectors is k-independent if all its subsets with no more than k elements are linearly independent. We obtain a result concerning the maximal possible cardinality Ind
q
(n, k) of a k-independent set of vectors in the n-dimensional vector space F
q
n
over the finite field F
q
of order q. Namely, we give a necessary and sufficient condition for Ind
q
(n, k) = n + 1. We conclude with some pertinent remarks re applications of our results to codes, graphs and hypercubes.
Supported, in part by grants EP/C000285, NSF-DMS-0439734 and NSF-DMS-0555839. S. B. Damelin thanks the Institute for Mathematics
and Applications for their hospitality. 相似文献
5.
In this paper, we characterize a C
*-subalgebra C
*(x) of B(H), generated by a single operator x. We show that if x is polar-decomposed by aq, where a is the partial isometry part and q is the positive operator part of x, then C
*(x) is *-isomorphic to the groupoid crossed product algebra
Aq×a\mathbbGa\mathcal{A}_{q}\times_{\alpha }\mathbb{G}_{a}
, where
Aq=C*(q)\mathcal{A}_{q}=C^{*}(q)
and
\mathbbGa\mathbb{G}_{a}
is the graph groupoid induced by a partial isometry part a of x. 相似文献
6.
As the main result, we show that if G is a finite group such that Γ(G) = Γ(2
F
4(q)), where q = 22m+1 for some m ≧ 1, then G has a unique nonabelian composition factor isomorphic to 2
F
4(q). We also show that if G is a finite group satisfying |G| =|2
F
4(q)| and Γ(G) = Γ(2
F
4(q)), then G ≅ 2
F
4(q). As a consequence of our result we give a new proof for a conjecture of W. Shi and J. Bi for 2
F
4(q).
The third author was supported in part by a grant from IPM (No. 87200022). 相似文献
7.
In this paper, we study the weighted (x(q + 1), x; 2, q)-minihypers. These are weighted sets of x(q + 1) points in PG(2, q) intersecting every line in at least x points. We investigate the decomposability of these minihypers, and define a switching construction which associates to an
(x(q + 1), x; 2, q)-minihyper, with x ≤ q
2 − q, not decomposable in the sum of another minihyper and a line, a (j(q + 1), j; 2, q)-minihyper, where j = q
2 − q − x, again not decomposable into the sum of another minihyper and a line. We also characterize particular (x(q + 1), x; 2, q)-minihypers, and give new examples. Additionally, we show that (x(q + 1), x; 2, q)-minihypers can be described as rational sums of lines. In this way, this work continues the research on (x(q + 1), x; 2, q)-minihypers by Hill and Ward (Des Codes Cryptogr 44:169–196, 2007), giving further results on these minihypers. 相似文献
8.
Jianqiang Zhao 《数学学报(英文版)》2008,24(10):1593-1616
In this paper, we shall define the renormalization of the multiple q-zeta values (MqZV) which are special values of multiple q-zeta functions ζq (s1,..., Sd) when the arguments are all positive integers or all non-positive integers. This generalizes the work of Guo and Zhang (Renormalization of Multiple Zeta Values, arxiv: math/0606076v3). We show that our renormalization process produces the same values if the MqZVs are well-defined originally and that these renormalizations of MqZV satisfy the q-stuffle relations if we use shifted-renormalizations for all divergent ζq(S1,..., sd) (i.e., s1 ≤ 1). Moreover, when q ↑ 1 our renormalizations agree with those of Guo and Zhang. 相似文献
9.
Sofiya Ostrovska 《Czechoslovak Mathematical Journal》2008,58(4):1195-1206
Due to the fact that in the case q > 1 the q-Bernstein polynomials are no longer positive linear operators on C[0, 1], the study of their convergence properties turns out to be essentially more difficult than that for q < 1. In this paper, new saturation theorems related to the convergence of q-Bernstein polynomials in the case q > 1 are proved. 相似文献
10.
Gerzson Kri 《组合设计杂志》2006,14(5):363-390
Based on the classification of superregular matrices, the numbers of non‐equivalent n‐arcs and complete n‐arcs in PG(r, q) are determined (i) for 4 ≤ q ≤ 19, 2 ≤ r ≤ q ? 2 and arbitrary n, (ii) for 23 ≤ q ≤ 32, r = 2 and n ≥ q ? 8<$>. The equivalence classes over both PGL (k, q) and PΓL(k, q) are considered throughout the examinations and computations. For the classification, an n‐arc is represented by the systematic generator matrix of the corresponding MDS code, without the identity matrix part of it. A rectangular matrix like this is superregular, i.e., it has only non‐singular square submatrices. Four types of superregular matrices are studied and the non‐equivalent superregular matrices of different types are stored in databases. Some particular results on t(r, q) and m′(r, q)—the smallest and the second largest size for complete arcs in PG(r, q)—are also reported, stating that m′(2, 31) = 22, m′(2, 32) = 24, t(3, 23) = 10, and m′(3, 23) = 16. © 2006 Wiley Periodicals, Inc. J Combin Designs 14: 363–390, 2006 相似文献
11.
Rosso and Green have shown how to embed the positive part Uq() of a quantum enveloping algebra Uq() in a quantum shuffle algebra. In this paper we study some properties of the image of the dual canonical basis B* of Uq() under this embedding . This is motivated by the fact that when is of type Ar, the elements of (B*) are q-analogues of irreducible characters of the affine Iwahori-Hecke algebras attached to the groups GL(m) over a p-adic field. 相似文献
12.
Xueyan Xiang Qian He Wenshan Yang 《分析论及其应用》2007,23(3):243-254
Recently, q-Bernstein polynomials have been intensively investigated by a number of authors. Their results show that for q ≠ 1, q-Bernstein polynomials possess of many interesting properties. In this paper, the convergence rate for iterates of both q-Bernstein polynomials and their Boolean sum are estimated. Moreover, the saturation of {Bn(., qn)} when n → ∞ and convergence rate of Bn(f,q;x) when f ∈ C^n-1 [0, 1], q → ∞ are also presented. 相似文献
13.
Given 1≤ p,q < ∞, let BLpLq be the class of all Banach lattices X such that X is isometrically lattice isomorphic to a band in some Lp(Lq)-Banach lattice. We show that the range of a positive contractive projection on any BLpLq-Banach lattice is itself in BLpLq. It is a consequence of this theorem and previous results that BLpLq is first-order axiomatizable in the language of Banach lattices. By studying the pavings of arbitrary BLpLq-Banach lattices by finite dimensional sublattices that are themselves in this class, we give an explicit set of axioms for
BLpLq. We also consider the class of all sublattices of Lp(Lq)-Banach lattices; for this class (when p/q is not an integer) we give a set of axioms that are similar to Krivine’s well-known axioms for the subspaces of Lp-Banach spaces (when p/2 is not an integer). We also extend this result to the limiting case q = ∞. 相似文献
14.
Shiro Iwasaki 《组合设计杂志》1997,5(2):95-110
Let p be an odd prime number such that p − 1 = 2em for some odd m and e ≥ 2. In this article, by using the special linear fractional group PSL(2, p), for each i, 1 ≤ i ≤ e, except particular cases, we construct a 2-design with parameters v = p + 1, k = (p − 1)/2i + 1 and λ = ((p − 1)/2i+1)(p − 1)/2 = k(p − 1)/2, and in the case i = e we show that some of these 2-designs are 3-designs. Likewise, by using the linear fractional group PGL(2,p) we construct an infinite family of 3-designs with the same v k and λ = k(k − 2). These supplement a part of [4], in which we gave an infinite family of 3-designs with parameters v = q + 1, k = (q + 1)/2 = (q − 1)/2 + 1 and λ = (q + 1)(q − 3)/8 = k(k − 2)/2, where q is a prime power such that q − 1 = 2m for some odd m and q > 7. Some of the designs given in this article and in [4] fill in a few blanks in the table of Chee, Colbourn, and Kreher [2]. © 1997 John Wiley & Sons, Inc. 相似文献
15.
The order components of a finite group are introduced in [12]. In [9], it is proved that the group PSL(3,q), where q is an odd prime power, is uniquely determined by its order components. In this paper, we show that the group PSL(3, q), where q=2
m
, is also uniquely determined by its order components.
Received December 15, 2000, Revised August 15, 2001, Accepted November 13, 2001 相似文献
16.
Cameron–Liebler line classes are sets of lines in PG(3, q) that contain a fixed number x of lines of every spread. Cameron and Liebler classified Cameron–Liebler line classes for x ∈ {0, 1, 2, q2 ? 1, q2, q2 + 1} and conjectured that no others exist. This conjecture was disproven by Drudge for q = 3 [8] and his counterexample was generalized to a counterexample for any odd q by Bruen and Drudge [4]. A counterexample for q even was found by Govaerts and Penttila [9]. Non‐existence results on Cameron–Liebler line classes were found for different values of x. In this article, we improve the non‐existence results on Cameron–Liebler line classes of Govaerts and Storme [11], for q not a prime. We prove the non‐existence of Cameron–Liebler line classes for 3 ≤ x < q/2. © 2007 Wiley Periodicals, Inc. J Combin Designs 16: 342–349, 2008 相似文献
17.
LetLbe a Moufang loop of odd orderpαqα11···qnαnwherepandqiare primes with 3 ≤ p < q1 < ··· < qnand αi ≤ 2. In this paper, we prove thatLis a group ifpandqiare primes with 3 ≤ p < q1 < ··· < qn: (i) α ≤ 3, or (ii) α ≤ 4,p ≥ 5. 相似文献
18.
Zhi Yuan HUANG Pei Yan LI Ying WU 《数学学报(英文版)》2008,24(2):201-214
The classical Levy-Meixner polynomials are distinguished through the special forms of their generating functions. In fact, they are completely determined by 4 parameters: c1, c2,γ and β. In this paper, for-1 〈q〈 1, we obtain a unified explicit form of q-deformed Levy-Meixner polynomials and their generating functions in term of c1, c2, γand β, which is shown to be a reasonable interpolation between classical case (q=1) and fermionic case (q=-1).In particular, when q=0 it's also compatible with the free case. 相似文献
19.
For q ≥ 0, Olsen [1] has attained the exact rate of convergence of the L
q
-spectrum of a self-similar measure and showed that the so-called empirical multifractal moment measures converges weakly
to the normalized multifractal measures. Unfortunately, nothing is known for q < 0. Indeed, the problem of analysing the L
q
- spectrum for q < 0 is generally considered significantly more difficult since the L
q
-spectrum is extremely sensitive to small variations of μ for q < 0. In [2] we showed that self-similar measures satisfying the Open Set Condition (OSC) are Ahlfors regular and, using this
fact, we obtained the exact rate of convergence of the L
q
-spectrum of a self-similar measure satisfying the OSC for q < 0. In this paper, we apply the results from [2] to show the empirical multifractal q’th moment measures of self-similar
measures satisfying the OSC converges weakly to the normalized multifractal Hausdorff measures for q < 0.
Authors’ addresses: Jiaqing Xiao, School of Science, Wuhan University of Technology, Wuhan 430070, China; Wu Min, School of
Mathematical Sciences, South China University of Technology, Guangzhou, 510640, China 相似文献
20.
Daniel S. Moak 《Aequationes Mathematicae》1980,21(1):179-191
F. H. Jackson defined aq analogue of the gamma function which extends theq-factorial (n!)
q
=1(1+q)(1+q+q
2)...(1+q+q
2+...+q
n–1) to positivex. Askey studied this function and obtained analogues of most of the classical facts about the gamma function, for 0<q<1. He proved an analogue of the Bohr-Mollerup theorem, which states that a logarithmically convex function satisfyingf(1)=1 andf(x+1)=[(q
x
–1)/(q–1)]f(x) is in fact theq-gamma function He also studied the behavior of
q
asq changes and showed that asq1–, theq-gamma function becomes the ordinary gamma function forx>0.I proved many of these results forq>1. The current paper contains a study of the behavior of
q
(x) forx<0 and allq>0. In addition to some basic properties of
q
, we will study the behavior of the sequence {x
n
(q)} of critical points asn orq changes. 相似文献