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排序方式: 共有5004条查询结果,搜索用时 15 毫秒
961.
We study and classify actions of the complex multiplicative group on a nonsingular Stein surface with an isolated nondicritical
singularity. We prove that the corresponding foliation exhibits a holomorphic first integral of a type F = f
n
g
m
where f and g are global holomorphic functions and . Under some additional conditions on the functions f and g we prove analytic linearization for the action. Our results can be viewed as extension of the original work of Masakazu Suzuki. 相似文献
962.
Olivier Brunat 《manuscripta mathematica》2009,129(4):483-497
This note is concerned with the unipotent characters of the Ree groups of type G
2. We determine the roots of unity associated by Lusztig and Digne-Michel to each unipotent character for and prove that the Fourier matrix of defined by Geck and Malle satisfies a conjecture of Digne-Michel. Our main tool is the Shintani descent of Ree groups of
type G
2. 相似文献
963.
Jana Björn 《Calculus of Variations and Partial Differential Equations》2009,35(4):481-496
We use variational methods to obtain a pointwise estimate near a boundary point for quasisubminimizers of the p-energy integral and other integral functionals in doubling metric measure spaces admitting a p-Poincaré inequality. It implies a Wiener type condition necessary for boundary regularity for p-harmonic functions on metric spaces, as well as for (quasi)minimizers of various integral functionals and solutions of nonlinear
elliptic equations on R
n . 相似文献
964.
In this paper, we are concerned with the effect of the domain topology on the multiplicity of solutions for some semilinear
elliptic systems involving critical Sobolev exponent. We show that if the interaction term is sufficiently small, then the
number of solutions of the system is estimated from below by 2 catΩ. The proof of this fact requires analysis of the structure
of the Nehari manifold associated with the system.
This research was partially supported by the Grant-in-Aid for Young Scientists (B), The Ministry of Education, Culture, Sports,
Science and Technology, Japan. 相似文献
965.
Thomas Schmidt 《NoDEA : Nonlinear Differential Equations and Applications》2009,16(1):109-129
We consider multi-dimensional variational integrals
where the integrand f is a strictly convex function of its last argument. We give an elementary proof for the partial -regularity of minimizers of F. Our approach is based on the method of A-harmonic approximation, avoids the use of Gehring’s lemma, and establishes partial regularity with the optimal H?lder exponent
α in a single step.
相似文献
966.
We present a Tikhonov regularization method for inclusions of the form where T is a set-valued mapping defined on a Banach space that enjoys metric regularity properties. We investigate, subsequently,
the case when the mapping T is metrically regular, strongly metrically regular, strongly subregular and Lipschitz continuous and show the strong convergence
of the solutions of regularized problems to a solution to the original inclusion . We also prove that the method has finite termination under some special conditioning assumptions on T and we study its stability with respect to some variational perturbations.
These authors are supported by Contract EA3591 (France). 相似文献
967.
In this paper, we consider a nonlinear elliptic equation driven by the p-Laplacian and with a parameter λ > 0. Using a combination of variational and degree theoretic methods, we show that there
exists λ* > 0 such that, if λ > λ*, then the problem has two positive smooth solutions. Our result extends earlier ones by Rabinowitz (semilinear equations)
and Guo (nonlinear equations).
相似文献
968.
Sebastian Król 《Journal of Evolution Equations》2009,9(3):449-468
The concept of the gap function is used to give new perturbation results for generators of holomorphic semigroups. In particular, we show that if A is the generator of a holomorphic semigroup on a Banach space and , then every closed linear operator C such that for some and
generates a holomorphic semigroup, too. Moreover, we obtain an analogue of this result for differences of semigroups. If T is a holomorphic semigroup and , then every C
0-semigroup S with
is holomorphic. We also give certain estimates for the constants M
A
and k
T
appearing in the above conditions.
The author was partially supported by the Marie Curie “Transfer of Knowledge” programme, project “TODEQ”, and by a MNiSzW
grant Nr N201384834. 相似文献
969.
Zen Harper 《Complex Analysis and Operator Theory》2009,3(1):113-146
We ask when convolution operators with scalar- or operator-valued kernel functions map between weighted L2 spaces of Hilbert space-valued functions. For a certain class of decreasing weights, including negative powers (t + a)−m for example, we solve the one-weight problem completely by using Laplace transforms and Bergman-type spaces of vector-valued
analytic functions. For a much more general class of decreasing weights, we solve the one-weight problem for all positive
real kernels (also for Lp(w) with p > 1), by results on Steklov operators which generalise the weighted Hardy inequality. When the kernel function is a strongly
continuous semigroup of bounded linear Hilbert space operators, which arises from input–output maps of certain linear systems,
then the most obvious sufficient condition for boundedness, obtained by taking norm signs inside the integrals, is also necessary
in many cases, but not in general.
Submitted: July 15, 2007.,Revised: November 19, 2007.,Accepted: December 14, 2007. 相似文献
970.
T. Len Miller Vivien G. Miller Michael M. Neumann 《Mediterranean Journal of Mathematics》2009,6(2):149-168
This paper centers on local spectral conditions that are both necessary and sufficient for the equality of the essential spectra
of two bounded linear operators on complex Banach spaces that are intertwined by a pair of bounded linear mappings. In particular,
if the operators T and S are intertwined by a pair of injective operators, then S is Fredholm provided that T is Fredholm and S has property (δ) in a neighborhood of 0. In this case, ind(T) ≤ ind(S), and equality holds precisely when the eigenvalues of the adjoint T* do not cluster at 0. By duality, we obtain refinements of results due to Putinar, Takahashi, and Yang concerning operators
with Bishop’s property (β) intertwined by pairs of operators with dense range. Moreover, we establish an extension of a result due to Eschmeier that,
under appropriate assumptions regarding the single-valued extension property, leads to necessary and sufficient conditions
for quasi-similar operators to have equal essential spectra. In particular it turns out that the single-valued extension property
plays an essential role in the preservation of the index in this context.
相似文献