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181.
182.
Hernán R. Henríquez 《Nonlinear Analysis: Theory, Methods & Applications》2009,71(12):6029-6037
Given a∈L1(R) and the generator A of an L1-integrable resolvent family of linear bounded operators defined on a Banach space X, we prove the existence of compact almost automorphic solutions of the semilinear integral equation for each f:R×X→X compact almost automorphic in t, for each x∈X, and satisfying Lipschitz and Hölder type conditions. In the scalar linear case, we prove that a∈L1(R) positive, nonincreasing and log-convex is sufficient to obtain the existence of compact almost automorphic solutions. 相似文献
183.
Stathis Chadjiconstantinidis 《Insurance: Mathematics and Economics》2009,44(2):278-286
In the present paper we develop more efficient recursive formulae for the evaluation of the t-order cumulative function Γth(x) and the t-order tail probability Λth(x) of the class of compound Poisson distributions in the case where the derivative of the probability generating function of the claim amounts can be written as a ratio of two polynomials. These efficient recursions can be applied for the exact evaluation of the probability function (given by De Pril [De Pril, N., 1986a. Improved recursions for some compound Poisson distributions. Insurance Math. Econom. 5, 129-132]), distribution function, tail probability, stop-loss premiums and t-order moments of stop-loss transforms of compound Poisson distributions. Also, efficient recursive algorithms are given for the evaluation of higher-order moments and r-order factorial moments about any point for this class of compound Poisson distributions. Finally, several examples of discrete claim size distributions belonging to this class are also given. 相似文献
184.
185.
The self‐destructive percolation model is defined as follows: Consider percolation with parameter p > pc. Remove the infinite occupied cluster. Finally, give each vertex (or, for bond percolation, each edge) that at this stage is vacant, an extra chance δ to become occupied. Let δc(p) be the minimal value of δ, needed to obtain an infinite occupied cluster in the final configuration. This model was introduced by van den Berg and Brouwer. They showed, for the site model on the square lattice (and a few other 2D lattices satisfying a special technical condition) that δc(p) ≥ . In particular, δc(p) is at least linear in p ? pc. Although the arguments used by van den Berg and Brouwer look very lattice‐specific, we show that they can be suitably modified to obtain similar linear lower bounds for δc(p) (with p near pc) for a much larger class of 2D lattices, including bond percolation on the square and triangular lattices, and site percolation on the star lattice (or matching lattice) of the square lattice. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009 相似文献
186.
We study Bernoulli type convolution measures on attractor sets arising from iterated function systems on R. In particular we examine orthogonality for Hankel frequencies in the Hilbert space of square integrable functions on the
attractor coming from a radial multiresolution analysis on R3. A class of fractals emerges from a finite system of contractive affine mappings on the zeros of Bessel functions. We have
then fractal measures on one hand and the geometry of radial wavelets on the other hand. More generally, multiresolutions
serve as an operator theoretic framework for the study of such selfsimilar structures as wavelets, fractals, and recursive
basis algorithms. The purpose of the present paper is to show that this can be done for a certain Bessel–Hankel transform.
Submitted: February 20, 2008., Accepted: March 6, 2008. 相似文献
187.
In this paper we are concerned with a family of elliptic operators represented as sum of square vector fields: , in where is the Laplace operator, , and the limit operator is hypoelliptic. It is well known that admits a fundamental solution . Here we establish some a priori estimates uniform in of it, using a modification of the lifting technique of Rothschild and Stein. As a consequence we deduce some a priori estimates uniform in , for solutions of the approximated equation . These estimates can be used in particular while studying regularity of viscosity solutions of nonlinear equations represented in terms of vector fields. 相似文献
188.
For X a compact Abelian group and B an infinite subset of its dual , let CB be the set of all x∈X such that converges to 1. If F is a free filter on , let 43" alt="View the MathML source" title="View the MathML source" src="http://ars.els-cdn.com/content/image/1-s2.0-S0166864105000568-si7.gif">. The sets CB and DF are subgroups of X. CB always has Haar measure 0, while the measure of DF depends on F. We show that there is a filter F such that DF has measure 0 but is not contained in any CB. This generalizes previous results for the special case where X is the circle group. 相似文献
189.
190.
Francisco J. Fernández-Polo 《Journal of Functional Analysis》2010,259(2):343-358
We establish several generalisations of Urysohn's lemma in the setting of JB∗-triples which provide full answers to Problems 1.12 and 1.13 in Fernández-Polo and Peralta (2007) [22]. These results extend the previous generalisations obtained by C.A. Akemann, G.K. Pedersen and L.G. Brown in the setting of C∗-algebras. A generalised Kadison's transitivity theorem is established for finite sums of pairwise orthogonal compact tripotents in JBW∗-triples. We introduce the notion of positively open tripotent in the bidual of a JB∗-triple as an extension of a concept which was already considered in the setting of ternary rings of operators. We investigate the connections appearing between positively open tripotents and hereditary inner ideals. 相似文献