Revista Matemática Complutense <p><em>Revista Matemática Complutense</em> (ISSN 1139-1138, ISSN-e 1988-2807), que edita en la actualidad tres fascículos al año, publica trabajos originales o recapitulativos cuidadosamente seleccionados de todas las áreas de la Matemática, entre ellos el artículo del “Conferenciante Santaló” que cada año recae en un matemático de gran prestigio. Desde enero de 2010, Springer se encarga de su publicación.</p> Springer es-ES Revista Matemática Complutense 1139-1138 <strong>LICENCIA DE USO</strong>: Los artículos a texto completo incluidos en el Portal de Revistas Científicas Complutenses son de acceso libre y propiedad de sus autores y/o editores. Por tanto, cualquier acto de reproducción, distribución, comunicación pública y/o transformación total o parcial requiere el consentimiento expreso y escrito de aquéllos. Cualquier enlace al texto completo de los artículos del Portal de Revistas Científicas Complutenses debe efectuarse a la URL oficial de la Universidad Complutense de Madrid Navier-Stokes/darcy coupling: modeling, analysis, and numerical approximation This pap er is an overview of known and new results ab out the coupling of Navier-Stokes and Darcy equations to model the filtration of incompressible fluids through p orous media. We discuss coupling conditions and we analyze the global coupled model in order to prove its well-p osedness and to characterize effective algorithms to compute the solution of its numerical approximation. Marco Discacciati Alfio Quarteroni ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 315 426 10.5209/rev_REMA.2009.v22.n2.16263 Coincidence of some classes of universal functions Let &#937; a domain in the complex plane such that &#937; satisfies appropriate geometrical and topological properties. We prove that if f is a holomorphic function in &#937;, then its Taylor series, with center at any &#958; &#1028; &#937; , is universal with respect to overconvergence if and only if its Cesáro (C, k)-means are universal for any real k > &#8722;1. This is an extension of the same result, proved recently by F. Bayart, for any integer k &#8805; 0. As a consequence, several classes of universal functions introduced in the related literature are shown to coincide. Emmanuel S. Katsoprinakis ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 427 445 10.5209/rev_REMA.2009.v22.n2.16279 Monodromy zeta-functions of deformations and Newton diagrams For a one-parameter deformation of an analytic complex function germ of several variables, there is defined its monodromy zeta-function. We give a Varchenko type formula for this zeta-function if the deformation is non-degenerate with respect to its Newton diagram. Gleb Gusev ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 447 454 10.5209/rev_REMA.2009.v22.n2.16282 Asymptotic uniform moduli and Kottman constant of Orlicz sequence spaces We give lower and upp er b ounds, involving moduli of asymptotic uniform con vexity and smoothness, for the Kottman separation constant of Orlicz sequence spaces equipp ed with the Luxemburg norm. Sylvain Delpech ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 455 467 10.5209/rev_REMA.2009.v22.n2.16285 Weighted composition operators between spaces of Dirichlet type In this work we characterize b oundedness and compactness of weighted comp osi tion op erators acting b etween Dirichlet typ e spaces by using Carleson measures. We also find essential norm estimates for these op erators. Sanjay Kumar ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 469 488 10.5209/rev_REMA.2009.v22.n2.16288 The SL(2,C)-character varieties of torus knots Let G b e the fundamental group of the complement of the torus knot of typ e (m, n). This has a presentation G = x, y | xm = y n . We find the geometric description of the character variety X (G) of characters of representations of G into SL(2, C). Vicente Muñoz ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 489 497 10.5209/rev_REMA.2009.v22.n2.16290 Symmetrization and sharp Sobolev inequalities in metric spaces We derive sharp Sob olev inequalities for Sob olev spaces on metric spaces. In particular, we obtain new sharp Sob olev emb eddings and Fab er-Krahn estimates for H¨rmander vector fields. o Mario Milman Jan Kališ ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 499 515 10.5209/rev_REMA.2009.v22.n2.16292 Erratum to “Fundamental groups of some special quadric arrangements” This erratum relates to our work “Fundamental groups of some special quadric arrangements”. The original Theorems 2.2, 2.5, 2.8 and Propositions 2.3(ii)(iii), 2.6(ii)(iii), 2.9(ii)(iii) have wrong results. They need to be rephrased. Corollaries 2.4 and 2.7 are incomplete, and they are extended. We add a new Corollary 2.10, which does not appear in the original paper. Proposition 3.1 has a wrong result and it is rephrased and reproved. In Proposition 4.1 and its Corollary 4.2 a slight error has occurred: as the correct proofs in the paper show, the monodromy is a quadruple fulltwist. Meirav Amram Mina Teicher ##submission.copyrightStatement## 2009-07-27 2009-07-27 22 2 517 550 10.5209/rev_REMA.2009.v22.n2.16299