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811.
Mihail?MeganEmail author Adina?Lumini?a?Sasu Bogdan?Sasu 《Integral Equations and Operator Theory》2004,50(4):489-504
The aim of this paper is to give necessary and sufficient conditions for pointwise and uniform exponential dichotomy of linear skew-product flows. We shall obtain that the pointwise exponential dichotomy of a linear skew-product flow is equivalent to the pointwise admissibility of the pair
As a consequence, we prove that a linear skew-product flow on
is uniformly exponentially dichotomic if and only if the pair
is uniformly admissible for . 相似文献
812.
Young Min?HanEmail author An-Hyun?KimEmail author 《Integral Equations and Operator Theory》2004,49(4):435-444
In this note we show that if either T or T* is totally *-paranormal
then Weyls theorem holds for f(T) for every f
, and also a-Weyls theorem holds for f(T) if T is totally *-paranormal. We prove that if either
T or T* is *-paranormal then the spectral mapping theorem holds for the
Weyl spectrum and for the essential approximate point spectrum. 相似文献
813.
Paolo?BoggiattoEmail author M. W.?WongEmail author 《Integral Equations and Operator Theory》2004,49(1):1-10
We give results on the boundedness and compactness of localization
operators with two admissible wavelets on
for the Weyl-Heisenberg
group. 相似文献
814.
Alessio?PorrettaEmail author 《NoDEA : Nonlinear Differential Equations and Applications》2004,11(4):407-430
We consider here a class of nonlinear Dirichlet problems, in a bounded domain , of the form
investigating the problem of uniqueness of solutions. The functions (s) and
satisfy rather general assumptions of locally Lipschitz continuity (with possibly exponential growth) and the datum f is in L1(). Uniqueness of solutions is proved both for coercive a(x, s) and for the case of a(x, s) degenerating for s large. 相似文献
815.
We show that if the group of holomorphic automorphisms of a connected complex manifold M of dimension n is isomorphic as a
topological group equipped with the compact-open topology to the automorphism group of the unit ball B
n ⊂ ℂ
n
,then M is biholomorphically equivalent to B
n. 相似文献
816.
The admissibility of observation operators and control operators for linear Volterra systems is studied by means of the theory of composition operators on Hardy spaces.Under certain assumptions it is shown to be equivalent to admissibility for the classical Cauchy problem. A duality between control and observation operators is also established,extending known results for the Cauchy problem,which is a special case. 相似文献
817.
A geometrical interpretation of the G-structures associated to elastic material bodies is given. In addition, characterizations of their integrability are obtained. Since the lack of integrability is a geometrical measure of the lack of homogeneity, the corresponding inhomogeneity conditions are obtained. 相似文献
818.
Neural Network Models for Finline Discontinuities 总被引:1,自引:0,他引:1
The radial basis network is used as the finline discontinuities electromagnetic artifical neural network(EMANN) models. EM software analysis is employed to characterize finline discontinuities. EMANN models are then trained using physical parameters and frequency as inputs and equivalent electric circuit element parameters of finline discontinuities as outputs. Once trained , the EMANN models can simulate equivalent electric circuit element parameters of finline step, notch and strip very fast and efficiently. 相似文献
819.
Horst Osswald 《Advances in Mathematics》2003,176(1):1-37
Using infinitesimals, we develop Malliavin calculus on spaces which result from the classical Wiener space by replacing with any abstract Wiener space .We start from a Brownian motion b on a Loeb probability space Ω with values in the Banach space is the standard part of a ∗finite-dimensional Brownian motion B. Then we define iterated Itô integrals as standard parts of internal iterated Itô integrals. The integrator of the internal integrals is B and the values of the integrands are multilinear forms on , where is a ∗finite-dimensional linear space over between the Hilbert space and its ∗-extension .In the first part we prove a chaos decomposition theorem for L2-functionals on Ω that are measurable with respect to the σ-algebra generated by b. This result yields a chaos decomposition of L2-functionals with respect to the Wiener measure on the standard space of -valued continuous functions on [0,1]. In the second part we define the Malliavin derivative and the Skorohod integral as standard parts of internal operators defined on ∗finite-dimensional spaces. In an application we use the transformation rule for finite-dimensional Euclidean spaces to study time anticipating and non-anticipating shifts of Brownian motion by Bochner integrals (Girsanov transformations). 相似文献
820.