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排序方式: 共有10000条查询结果,搜索用时 383 毫秒
991.
This paper is concerned with large- error estimates concerning convergence in distribution as well as norm convergence for Banach space-valued martingale difference sequences. Indeed, two general limit theorems equipped with rates of convergence for such difference sequences are established. Applications of these lead to the central limit theorem and the weak law of large numbers with rates for Banach space-valued martingales. 相似文献
992.
Elena Cordero Stevan Pilipović Luigi Rodino Nenad Teofanov 《Mediterranean Journal of Mathematics》2005,2(4):381-394
We study localization operators within the framework of ultradistributions. More precisely, given a symbol a and two windows φ1, φ2, we investigate the multilinear mapping from
to the localization operator
Results are formulated in terms of modulation spaces with weights which may have exponential growth. We give sufficient and
necessary conditions for
a to be bounded or to belong to a Schatten class. As an application, we study symbols defined by ultra-distributions with
compact support, that give trace class localization operators. 相似文献
993.
We prove the existence of positive symmetric solutions to the semilinear elliptic problem
in both the radial case N = k ≥ 3 and the cylindrical case N ≥ k + 3 ≥ 6. The potential V is measurable, positive and it is only required to satisfy a mild integrability condition. The nonlinearity is continuous
and has a doublepower behavior, super-critical near the origin and sub-critical at infinity. If f is odd, we show that the radial problem has infinitely many solutions. In proving these results we exploit the compactness
of suitable restrictions of the embedding
Supported by MIUR, project “Variational Methods and Nonlinear Differential Equations”. 相似文献
994.
Óscar Ciaurri 《Rendiconti del Circolo Matematico di Palermo》2004,53(2):231-234
A transference theorem for multipliers of Hermite expansions is proved. The result allows to transfer weightedL
2(ℝ
n
) estimates from lower to higher dimensions.
Research of the author supported by grant BFM2003-06335-603-03 of the D.G.I.. 相似文献
995.
B. Yousefi 《Archiv der Mathematik》2004,83(6):536-539
Let
be a Hilbert space of functions analytic on a plane domain such that for every in the functional of evaluation at is bounded. Assume further that
contains the constants and admits multiplication by the independent variable z, Mz, as a bounded operator. We give sufficient conditions for Mz to be reflexive.Received: 17 February 2004 相似文献
996.
We introduce the concept of topological finite-determinacy for
germs of analytic functions within a fixed ideal
I, which provides a notion of topological finite-determinacy
of functions with non-isolated singularities. We prove the following statement
which generalizes classical results of Thom and Varchenko: let
A be the complement in the ideal I of the space
of germs whose topological type remains unchanged under a
deformation within the ideal that only modifies sufficiently
large order terms of the Taylor expansion. Then A has infinite
codimension in I in a suitable sense. We also prove the
existence of generic topological types of families of germs of
I parametrized by an irreducible analytic set. 相似文献
997.
We classify the irreducible components of the varieties
\[
\V(n,a,b) = \{ (A,B) \in \M_n(\field) \times \M_n(\field) \mid
AB = BA = A^a = B^b = 0 \}.
\] 相似文献
998.
The forms of the exceptional simple classical Lie
superalgebras are determined over arbitrary fields of
characteristic $\ne 2,3$. 相似文献
999.
Jaume Giné 《Journal of Differential Equations》2004,197(1):147-161
We consider the class of polynomial differential equations , where Pn and Qn are homogeneous polynomials of degree n. These systems have a focus at the origin if λ≠0, and have either a center or a focus if λ=0. Inside this class we identify a new subclass of Darbouxian integrable systems having either a focus or a center at the origin. Additionally, under generic conditions such Darbouxian integrable systems can have at most one limit cycle, and when it exists is algebraic. For the case n=2 and 3, we present new classes of Darbouxian integrable systems having a focus. 相似文献
1000.
This paper is concerned with the existence, smoothness and attractivity of invariant manifolds for evolutionary processes on general Banach spaces when the nonlinear perturbation has a small global Lipschitz constant and locally Ck-smooth near the trivial solution. Such a nonlinear perturbation arises in many applications through the usual cut-off procedure, but the requirement in the existing literature that the nonlinear perturbation is globally Ck-smooth and has a globally small Lipschitz constant is hardly met in those systems for which the phase space does not allow a smooth cut-off function. Our general results are illustrated by and applied to partial functional differential equations for which the phase space (where r>0 and being a Banach space) has no smooth inner product structure and for which the validity of variation-of-constants formula is still an interesting open problem. 相似文献