Roanes-Lozano, Eugenio Laita, Luis M. Hernando, Antonio Roanes-Macías, Eugenio
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

This article presents a survey of the authors' research on knowledge extraction and verification of Rule Based Expert Systems (RBES) using algebraic inference engines and based on Gröbner bases theory. A shell, including a graphic user interface and inference engines for different logics (both classic and modal multi-valued) as well as in different...

Tyszkowska, Ewa
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

A compact Riemann surface X of genus g > 1 is saID to be a p-hyperelliptic if X admits a conformal involution ρ for which X/ρ has genus p. This notion is the particular case of so called cyclic (q, n)-gonal surface which is defined as the one admitting a conformal automorphism δ of order n such that X/δ has genus q. It is known that for g > 4 p + 1...

Bartolini, Gabriel Costa, Antonio F. Izquierdo, Milagros Porto, Ana M.
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

The moduli space \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$ \mathcal{M}_g $$ \end{document} of compact Riemann surfaces of genus g has the structure of an orbifo...

Piszczek, Krzysztof
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

We characterize quasi-reflexive barrelled and complete locally convex Hausdorff spaces with a basis in terms of the properties of this basis. Moreover we prove that a complete, barrelled lcHs with a basis is quasi-reflexive of order one if and only if for every power bounded operator T, either T or T′ is mean ergodic.

Necula, Mihai Popescu, Marius Vrabie, Ioan I.
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

Let X be a real Banach space, let A: D(A) ⊆ X ⇝ X be an m-dissipative operator, let I a nonempty, bounded interval And let K: \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{docum...

Monterde, Ignacio Montesinos, Vicente Valdivia, Manuel
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

We prove that Eberlein's theorem holds for the Mackey * topology in the dual X* of a Banach space. This improves a result of Howard. We prove, too, that in general the space X* endowed with the Mackey * topology is not angelic.

Díaz, Jesús Ildefonso Glowinski, Roland GuIDoboni, Giovanna Kim, Taebeom
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

We study the transient flow of an isothermal and incompressible Bingham fluID. Similar models arise in completely different contexts as, for instance, in material science, image processing and differential geometry. For the two-dimensional flow in a bounded domain we show the extinction in a finite time even under suitable nonzero external forces. ...

Wójtowicz, Marek Sieg, Waldemar
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

Let X be a completely regular (Tychonoff) space, and let C(X), U(X), and B1(X) denote the sets of all real-valued functions on X that are continuous, have a closed graph, and of the first Baire class, respectively. We prove that U(X) = C(X) if and only if X is a P-space (i.e., every Gδ-subset of X is open) if and only if B1(X = U(X). This extends a...

López-Pouso, Óscar Muñoz-Sola, Rafael
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RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

This paper studies the existence and uniqueness questions, in classical spaces, for a certain system of differential equations. From the physical point of view, the interest of this system lies in that it becomes, for particular choices of its coefficients, the even parity formulation of the S2 approximation of the transient radiative heat transfer...

Xiaosha, Zhou Lanzhe, Liu
Published in
RACSAM - Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas

In this paper, we prove some weighted boundedness for the multilinear operators related to some singular integral operators with non-smooth kernels on the generalized Morrey spaces by using a sharp function estimate of the multilinear operators.