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121.
Marius Ghergu 《International Journal of Mathematical Education in Science & Technology》2018,49(5):802-807
We explore the connection between the notion of critical point for a function of one variable and various inequalities for iterated exponentials defined on the positive semiline of real numbers. 相似文献
122.
Global analysis of the shadow Gierer-Meinhardt system with general linear boundary conditions in a random environment 下载免费PDF全文
Kwadwo Antwi-Fordjour Seonguk Kim Marius Nkashama 《Journal of Applied Analysis & Computation》2020,10(5):1980-1994
The global analysis of the shadow Gierer-Meinhardt system with multiplicative white noise and general linear boundary conditions is investigated in this paper.
For this reaction-diffusion system, we employ a fixed point argument to prove local existence and uniqueness. Our results on global existence are based on \emph{a priori} estimates of solutions. 相似文献
123.
We study the fully inhomogeneous Dirichlet problem for the Laplacian in bounded convex domains in Rn, when the size/smoothness of both the data and the solution are measured on scales of Besov and Triebel-Lizorkin spaces. As a preamble, we deal with the Dirichlet and Regularity problems for harmonic functions in convex domains, with optimal nontangential maximal function estimates. As a corollary, sharp estimates for the Green potential are obtained in a variety of contexts, including local Hardy spaces. A substantial part of this analysis applies to bounded semiconvex domains (i.e., Lipschitz domains satisfying a uniform exterior ball condition). 相似文献
124.
The dirichlet problem in lipschitz domains for higher order elliptic systems with rough coefficients
Vladimir. Maz’ya Marius Mitrea Tatyana Shaposhnikova 《Journal d'Analyse Mathématique》2010,110(1):167-239
We study the Dirichlet problem, in Lipschitz domains and with boundary data in Besov spaces, for divergence form strongly
elliptic systems of arbitrary order with bounded, complex-valued coefficients. A sharp corollary of our main solvability result
is that the operator of this problem performs an isomorphism between weighted Sobolev spaces when its coefficients and the
unit normal of the boundary belong to the space VMO. 相似文献
125.
Mark S. Ashbaugh Fritz Gesztesy Marius Mitrea Gerald Teschl 《Advances in Mathematics》2010,223(4):1372-885
We study spectral properties for HK,Ω, the Krein-von Neumann extension of the perturbed Laplacian −Δ+V defined on , where V is measurable, bounded and nonnegative, in a bounded open set Ω⊂Rn belonging to a class of nonsmooth domains which contains all convex domains, along with all domains of class C1,r, r>1/2. In particular, in the aforementioned context we establish the Weyl asymptotic formula
126.
Saturated models constitute one of the powerful methods of conventional model theory, with many applications. Here we develop
a categorical abstract model theoretic approach to saturated models within the theory of institutions. The most important
consequence is that the method of saturated models becomes thus available to a multitude of logical systems from logic or
from computing science. In this paper we define the concept of saturated model at an abstract institution-independent level
and develop the fundamental existence and uniqueness theorems. As an application we prove a general institution-independent
version of the Keisler–Shelah isomorphism theorem “any two elementarily equivalent models have isomorphic ultrapowers” (assuming
Generalized Continuum Hypothesis). 相似文献
127.
The aim of this article is twofold. On the one hand, we study the well-posedness of the Lamé system ${-\mu\Delta-\mu'\nabla{\rm div} }The aim of this article is twofold. On the one hand, we study the well-posedness of the Lamé system -mD-m¢?div{-\mu\Delta-\mu'\nabla{\rm div} } in L
q
(Ω), where Ω is an open subset of
\mathbbRn{{\mathbb{R}}^n} satisfying mild regularity assumptions and the Lamé moduli μ, μ′ are such that μ > 0 and μ + μ′ > 0. On the other hand, we prove the analyticity of the semigroup generated by the Lamé operator as well as the maximal
regularity property for the time-dependent Lamé system equipped with a homogeneous Dirichlet boundary condition based on off-diagonal
estimates. 相似文献
128.
Multivariate Hierarchical Copulas with Shocks 总被引:2,自引:0,他引:2
Fabrizio Durante Marius Hofert Matthias Scherer 《Methodology and Computing in Applied Probability》2010,12(4):681-694
A transformation to obtain new multivariate hierarchical copulas, starting with an arbitrary copula, is introduced. In addition
to the hierarchical structure, the presented construction principle explicitly supports singular components. These may be
interpreted as the effect of local or global shocks to the underlying random variables. A large spectrum of dependence patterns
can be achieved by the presented transformation, which seems promising for practical applications. Moreover, copulas arising
from this construction are similarly admissible with respect to analytical tractability and sampling routines as the original
copula. Finally, several well-known families of copulas may be interpreted as special cases. 相似文献
129.
The goal of this article is to study finite groups admitting a pseudocomplemented subgroup lattice (PK-groups) or a pseudocomplemented normal subgroup lattice (PKN-groups). In particular, we obtain a complete classification of finite PK-groups and of finite nilpotent PKN-groups. We also study groups with a Stone normal subgroup lattice, and we classify finite groups for which every subgroup has a Stone normal subgroup lattice. Finally, we obtain a complete classification of finite groups for which every subgroup is monolithic. 相似文献
130.
This article introduces a graphical goodness-of-fit test for copulas in more than two dimensions. The test is based on pairs of variables and can thus be interpreted as a first-order approximation of the underlying dependence structure. The idea is to first transform pairs of data columns with the Rosenblatt transform to bivariate standard uniform distributions under the null hypothesis. This hypothesis can be graphically tested with a matrix of bivariate scatterplots, Q-Q plots, or other transformations. Furthermore, additional information can be encoded as background color, such as measures of association or (approximate) p-values of tests of independence. The proposed goodness-of-fit test is designed as a basic graphical tool for detecting deviations from a postulated, possibly high-dimensional, dependence model. Various examples are given and the methodology is applied to a financial dataset. An implementation is provided by the R package copula. Supplementary material for this article is available online, which provides the R package copula and reproduces all the graphical results of this article. 相似文献