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81.
Nous présentons un cadre unificateur pour un certain nombre de résultats connus de convergence en loi pour des processus admettant une représentation linéaire par rapport à un bruit blanc faible pour lequel il existe un principe dinvariance faible. Nous montrons que ce principe dinvariance est équivalent à la convergence dune suite de mesures aléatoires spectrales. Ceci permet daffaiblir les hypothèses usuelles et donc dobtenir des résultats nouveaux de convergence en loi, notamment pour des processus à longue portée. 相似文献
82.
Ralf Kornhuber 《Numerische Mathematik》1996,72(4):481-499
Summary.
We derive globally convergent multigrid methods
for discrete elliptic
variational inequalities of the second kind
as obtained from
the approximation of related continuous
problems by piecewise linear finite elements.
The coarse grid corrections are computed
from certain obstacle problems.
The actual constraints are fixed by the
preceding nonlinear fine grid smoothing.
This new approach allows the implementation
as a classical V-cycle and preserves
the usual multigrid efficiency.
We give estimates
for the asymptotic convergence rates.
The numerical results indicate a significant improvement
as compared with previous multigrid approaches.
Received
March 26, 1994 / Revised version received September 22, 1994 相似文献
83.
84.
Martino Prizzi 《Journal of Differential Equations》2005,210(2):429-451
We study a non-autonomous parabolic equation with almost-periodic, rapidly oscillating principal part and nonlinear interactions. We associate to the equation a skew-product semiflow and, for a special class of nonlinearities, we define the Conley index of isolated compact invariant sets. As the frequency of the oscillations tends to infinity, we prove that every isolated compact invariant set of the averaged autonomous equation can be continued to an isolated compact invariant set of the skew-product semiflow associated to the non-autonomous equation. Finally, we illustrate some examples in which the Conley index can be explicitly computed and can be exploited to detect the existence of recurrent dynamics in the equation. 相似文献
85.
In this paper we introduce a modal theory which is sound and complete for arithmetical -interpretations in , in other words, we will show that is the -provability logic of . Moreover we will show that is decidable. As a by-product of these results, we show that has de Jongh property. 相似文献
86.
Sergio Albeverio Yuri Kondratiev Roman Nikiforov Grygoriy Torbin 《Bulletin des Sciences Mathématiques》2014
The paper is devoted to the study of fractal properties of subsets of the set of non-normal numbers with respect to Rényi f -expansions generated by continuous increasing piecewise linear functions defined on [0,+∞). All such expansions are expansions for real numbers generated by infinite linear IFS f={f0,f1,…,fn,…} with the following list of ratios Q∞=(q0,q1,…,qn,…). 相似文献
87.
Egor A. Alekhno 《Positivity》2009,13(1):3-20
Let T be a positive operator on a Banach lattice E. Some properties of Weyl essential spectrum σew(T), in particular, the equality , where is the set of all compact operators on E, are established. If r(T) does not belong to Fredholm essential spectrum σef(T), then for every a ≠ 0, where T−1 is a residue of the resolvent R(., T) at r(T). The new conditions for which implies , are derived. The question when the relation holds, where is Lozanovsky’s essential spectrum, will be considered. Lozanovsky’s order essential spectrum is introduced. A number of
auxiliary results are proved. Among them the following generalization of Nikol’sky’s theorem: if T is an operator of index zero, then T = R + K, where R is invertible, K ≥ 0 is of finite rank. Under the natural assumptions (one of them is ) a theorem about the Frobenius normal form is proved: there exist T-invariant bands such that if
, where , then an operator on Di is band irreducible.
相似文献
88.
P. Christopher Staecker 《Journal of Fixed Point Theory and Applications》2009,5(2):237-247
We give axioms which characterize the local Reidemeister trace for orientable differentiable manifolds. The local Reidemeister
trace in fixed point theory is already known, and we provide both uniqueness and existence results for the local Reidemeister
trace in coincidence theory. 相似文献
89.
Alex Chigogidze 《Topology and its Applications》2006,153(7):1079-1083
It is shown that a nonmetrizable ANR-space of weight τ>ω, admitting a group structure, is (topologically) an Rτ-manifold. 相似文献
90.
A surface wave in a planar nonlinear waveguide is a current problem that has several applications in modern electronics and optics such as optical sensors design. The effect of thermal stress on the optical performance of a nonlinear symmetrical sensor is studied. The mathematical forms of the dispersion equation and thermal-stress sensitivity are analytically derived and plotted numerically. It is found that the thermal sensitivity of the sensor can be controlled by tuning the core size, by changing the loading materials, and by carefully selecting the materials. 相似文献