All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 12 Next

Displaying 221 – 240 of 687

Showing per page

Finite element approximations of a glaciology problem

Sum S. Chow, Graham F. Carey, Michael L. Anderson (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

In this paper we study a model problem describing the movement of a glacier under Glen's flow law and investigated by Colinge and Rappaz [Colinge and Rappaz, ESAIM: M2AN33 (1999) 395–406]. We establish error estimates for finite element approximation using the results of Chow [Chow, SIAM J. Numer. Analysis29 (1992) 769–780] and Liu and Barrett [Liu and Barrett, SIAM J. Numer. Analysis33 (1996) 98–106] and give an analysis of the convergence of the successive approximations used in [Colinge and...

First Order Characterizations of Pseudoconvex Functions

Ivanov, Vsevolod (2001)

Serdica Mathematical Journal

First order characterizations of pseudoconvex functions are investigated in terms of generalized directional derivatives. A connection with the invexity is analysed. Well-known first order characterizations of the solution sets of pseudolinear programs are generalized to the case of pseudoconvex programs. The concepts of pseudoconvexity and invexity do not depend on a single definition of the generalized directional derivative.

First-Order Conditions for Optimization Problems with Quasiconvex Inequality Constraints

Ginchev, Ivan, Ivanov, Vsevolod I. (2008)

Serdica Mathematical Journal

2000 Mathematics Subject Classification: 90C46, 90C26, 26B25, 49J52.The constrained optimization problem min f(x), gj(x) ≤ 0 (j = 1,…p) is considered, where f : X → R and gj : X → R are nonsmooth functions with domain X ⊂ Rn. First-order necessary and first-order sufficient optimality conditions are obtained when gj are quasiconvex functions. Two are the main features of the paper: to treat nonsmooth problems it makes use of Dini derivatives; to obtain more sensitive conditions, it admits directionally...

Fonctions séparément analytiques

Jean Saint Raymond (1990)

Annales de l'institut Fourier

On étudie les fonctions de deux variables réelles qui sont séparément analytiques sur un ouvert du plan. On montre que ces fonctions sont analytiques en tout point du domaine de définition hors d’un fermé de ce domaine dont les projections sur chacun des deux axes de coordonnées sont des ensembles polaires. Inversempent, pour tout tel fermé F , on construit une fonction séparément analytique dont le domaine d’analyticité est le complémentaire de F .

From the Prékopa-Leindler inequality to modified logarithmic Sobolev inequality

Ivan Gentil (2008)

Annales de la faculté des sciences de Toulouse Mathématiques

We develop in this paper an improvement of the method given by S. Bobkov and M. Ledoux in [BL00]. Using the Prékopa-Leindler inequality, we prove a modified logarithmic Sobolev inequality adapted for all measures on ℝ n , with a strictly convex and super-linear potential. This inequality implies modified logarithmic Sobolev inequality, developed in [GGM05, GGM07], for all uniformly strictly convex potential as well as the Euclidean logarithmic Sobolev inequality.

Functions of bounded variation on compact subsets of the plane

Brenden Ashton, Ian Doust (2005)

Studia Mathematica

A major obstacle in extending the theory of well-bounded operators to cover operators whose spectrum is not necessarily real has been the lack of a suitable variation norm applicable to functions defined on an arbitrary nonempty compact subset σ of the plane. In this paper we define a new Banach algebra BV(σ) of functions of bounded variation on such a set and show that the function-theoretic properties of this algebra make it better suited to applications in spectral theory than those used previously....

Functions of bounded variation, signed measures, and a general Koksma-Hlawka inequality

Christoph Aistleitner, Josef Dick (2015)

Acta Arithmetica

We prove a correspondence principle between multivariate functions of bounded variation in the sense of Hardy and Krause and signed measures of finite total variation, which allows us to obtain a simple proof of a generalized Koksma-Hlawka inequality for non-uniform measures. Applications of this inequality to importance sampling in Quasi-Monte Carlo integration and tractability theory are given. We also discuss the problem of transforming a low-discrepancy sequence with respect to the uniform measure...

Functions of finite fractional variation and their applications to fractional impulsive equations

Dariusz Idczak (2017)

Czechoslovak Mathematical Journal

We introduce a notion of a function of finite fractional variation and characterize such functions together with their weak σ -additive fractional derivatives. Next, we use these functions to study differential equations of fractional order, containing a σ -additive term—we prove existence and uniqueness of a solution as well as derive a Cauchy formula for the solution. We apply these results to impulsive equations, i.e. equations containing the Dirac measures.

Functions with prescribed singularities

Giovanni Alberti, S. Baldo, G. Orlandi (2003)

Journal of the European Mathematical Society

The distributional k -dimensional Jacobian of a map u in the Sobolev space W 1 , k − 1 which takes values in the sphere S k − 1 can be viewed as the boundary of a rectifiable current of codimension k carried by (part of) the singularity of u which is topologically relevant. The main purpose of this paper is to investigate the range of the Jacobian operator; in particular, we show that any boundary M of codimension k can be realized as Jacobian of a Sobolev map valued in S k − 1 . In case M is polyhedral, the map we construct...

Currently displaying 221 – 240 of 687