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101.
设T是m-增生算子,I是恒等映射.本文通过一个反例说明(T+λI)-1(λ>0)不一定是非扩张映射. 相似文献
102.
Hiroshi Sato 《Journal of Theoretical Probability》1992,5(2):349-353
The aim of this paper is to characterize the nuclearity of an integral operator, defined by a continuous non-negative definite square integrable kernel on a separable metric space, in terms of the integrability of the trace of the kernel function. Nuclearity here plays a role forU-statistics. 相似文献
103.
Miao Changxing 《数学学报(英文版)》1997,13(2):247-268
We consider the scattering problem for the Hartree equation with potential |x|−1 in a space of dimensionn≥2. We prove the existence ofH
m
-modified wave operator for Hartree equation on a dense set of a neighborhood of zero inH
m
(ℝ
n
), meanwhile, we obtain also the global existence for the Cauchy problem of Hartree equation in a space of dimensionn≥2.
This project is supported by the National Natural Science Foundation of China, 19601005 相似文献
105.
We construct a series of pairs of domains in the plane and pairs of surfaces with boundary that are isospectral but not isometric.
The construction is based on the existence of finite transformation groups that are spectrally equivalent but not isomorphic.
Translated fromMatematicheskie Zametki, Vol. 63, No. 5, pp. 660–664, May, 1998.
This research was partially supported by the Russian Foundation for Basic Research and by INTAS under joint grant No. 96-01-00043. 相似文献
106.
In this paper κ-order slant Toeplitz operator on the Bergman space is defined. Some properties like spectrum, commuting are discussed. 相似文献
107.
We introduce a family of matrices that define logics in which paraconsistency and/or paracompleteness occurs only at the level of literals, that is, formulas that are propositional letters or their iterated negations. We give a sound and complete axiomatization for the logic defined by the class of all these matrices, we give conditions for the maximality of these logics and we study in detail several relevant examples. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
Nicolas Bouleau 《Journal of Functional Analysis》2007,251(1):325-345
The error on a real quantity Y due to the graduation of the measuring instrument may be asymptotically represented, when the graduation is regular and fines down, by a Dirichlet form on R whose square field operator does not depend on the probability law of Y as soon as this law possesses a continuous density. This feature is related to the “arbitrary functions principle” (Poincaré, Hopf). We give extensions of this property to Rd and to the Wiener space for some approximations of the Brownian motion. This gives new approximations of the Ornstein-Uhlenbeck gradient. These results apply to the discretization of some stochastic differential equations encountered in mechanics. 相似文献
109.
110.
A. Ducrot 《Mathematical Methods in the Applied Sciences》2007,30(3):291-304
This paper is devoted to the study of multi‐dimensional travelling wave solution for a thermo‐diffusive model, describing the propagation of curved flames in an infinite cylinder. The linear dependence of the components of the reaction rate together with the existence of an ignition temperature ensure that the corresponding linearized operator does not satisfy the Fredholm property. A direct consequence is that solvability conditions for the linearized operator are not known and classical methods of nonlinear analysis cannot be directly applied. We prove in this paper existence results of such travelling waves, by first introducing a suitable re‐formulation of the equations and then by choosing suitable weighted spaces that allows us to move the essential spectrum away from zero. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献