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151.
In this paper we prove the existence and uniqueness of global weak solutions to the weakly dissipative Camassa-Holm equation.  相似文献   
152.
We provide a generalization of a recent result of Anastassiou related to thewell-known Ostrowski inequality, as well as some related results. Ourresults subsume, extend, and consolidate a number of known results.  相似文献   
153.
The derived projective limit functor Proj¹ is a very useful tool for investigating surjectivity problems in various parts of analysis (e.g. solvability of partial differential equations).

We provide a new characterization for vanishing Proj¹ on projective spectra of (LB)-spaces which improves a classical result of V. P. Palamodov and V. S. Retakh.

  相似文献   

154.
This paper deals with the class of continuous-time linear systems with Markovian jumps and multiple time delays. The systems that we are treating are assumed to have time-varying delays in their dynamics which can be different and also have uncertainties in the system parameters. The time-varying structure of the bounded uncertainties is considered. Delay-dependent conditions for stochastic stability and stochastic stabilizability and their robustness are considered. A design algorithm for a stabilizing memoryless controller is proposed. All the results are given in the LMI formalism.  相似文献   
155.
We study the attractors of a finite system of planar contraction similarities S j (j=1,...,n) satisfying the coupling condition: for a set {x 0,...,x n} of points and a binary vector (s 1,...,s n ), called the signature, the mapping S j takes the pair {x 0,x n} either into the pair {x j-1,x j } (if s j =0) or into the pair {x j , x j-1} (if s j =1). We describe the situations in which the Jordan property of such attractor implies that the attractor has bounded turning, i.e., is a quasiconformal image of an interval of the real axis.  相似文献   
156.
In this paper it is proved that the ideal of trace-class operators acting in a couple of Hilbert spaces coincides with the ideal of coherent trace-class operators. A new formula is derived for theK-functional in the couple of algebras of all bounded linear operators acting in a Hilbert couple, and new interpolation theorems are proved for trace class operators.Translated fromMatematicheskie Zametki, Vol. 63, No. 6, pp. 866–872, June, 1998.This research was partially supported by the International Science Foundation and the Russian Government under grant JD 7100.  相似文献   
157.
Yakymiv  A. L. 《Mathematical Notes》2003,73(1-2):280-288
Under weak constraints on the positive functions to be compared, we derive their asymptotic equivalence at infinity as a consequence of the asymptotic equivalence of their Stieltjes transforms at infinity.  相似文献   
158.
A nonnegative 1-periodic multifractal measure on is obtained as infinite random product of harmonics of a 1-periodic function W(t). Such infinite products are statistically self-affine and generalize certain Riesz products with random phases. They are martingale structures, therefore converge. The criterion on W for nondegeneracy is provided. It differs completely from those for other known random measures constructed as martingale limits of multiplicative processes. In particular, it is very sensitive to small changes in W(t). When these infinite products are interpreted in the framework of thermodynamic formalism for random transformations, logW is a potential function when W>0. For regular enough potentials, in case of degeneracy, the natural normalization makes the sequence of measures converge. Moreover, this normalization is neutral for nondegenerate martingales. The multifractal analysis of the limit martingale measure is performed for a class of potential functions having a dense countable set of jump points.  相似文献   
159.
Abstruct The algebra describing a shock measure in the asymmetric simple exclusion model, seen from a second class particle, has finite-dimensional representations if and only if the asymmetry parameterp of the model and the left and right asymptotic densitiesp ± of the shock satisfy [(1−p)/p] r =p (1−p +)/p +(1−p ) for some integerr≥1; the minimal dimension of the representation is then 2r. These representations can be used to calculate correlation functions in the model.  相似文献   
160.
姚景齐 《数学学报》1997,40(5):665-668
在空间Lp(Rn),1≤p<∞中,Poison算子半群e--△z是右半平面Rez>0上的解析半群.本文考虑它的边界值,证明了闭稠定算子-i-△对某个α≥0生成了一个指数有界(I+-△)-α 半群.  相似文献   
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