Información de la editorial
Documentos disponibles de esta editorial (22)
Añadir el resultado a su cesta Hacer una sugerencia Refinar búsqueda
texto impreso
Using some model-theoretic arguments applied to the theory of real valuations, we obtain a sufficient condition based on elementary properties of , K any real closed field, for ƒ to be sum of 2mth powers of rational functions in K(x).texto impreso
We correct a previously published theorem by proving a criterion to decide whether the fibration given by a real polynomial function f : R-2 --> R is locally trivial at infinity. The algorithmical nature of this criterion provides a test that c[...]texto impreso
A compact Klein surface with boundary of algebraic genus g?2 has at most 12(g?1) automorphisms. When a surface attains this bound we say that it has maximal symmetry, and the group of automorphisms is then an M group. In this paper we exhibit fo[...]texto impreso
Abánades, Miguel A. ; Joglar-Prieto, Nuria ; Ruiz Sancho, Jesús María | Elsevier Science B.V. (North-Holland) | 1999-10-01We show that the ring of bounded meromorphic functions on an irreducible compact real analytic set of dimension d is a Prüfer domain of dimension d. Consequently, every finitely generated ideal in this ring can be generated by d + 1 elements, an[...]texto impreso
Giraldo, A. ; Morón, Manuel A. ; Romero Ruiz del Portal, Francisco ; Rodríguez Sanjurjo, José Manuel | Elsevier Science B.V. (North-Holland) | 2001-09-07We show in this paper how to represent intrinsically Cech homology of compacta, in terms of inverse limits of discrete approximations. We establish some relations between inverse limits and non-continuous homotopies and, as a consequence, we get[...]texto impreso
Arrondo Esteban, Enrique ; Sendra, Juana ; Sendra, J. Rafael | Elsevier Science B.V. (North-Holland) | 1999In this paper, we present a formula for computing the genus of irreducible generalized offset curves to projective irreducible plane curves with only affine ordinary singularities over an algebraically closed field. The formula expresses the gen[...]texto impreso
We study Hamburger-Noether matrices over rings, obtaining some applications to deformations of curves and equisingularity. We also study a special type of them, the matrices of Arf.texto impreso
A morphism of a category which is simultaneously an epimorphism and a monomorphism is called a bimorphism. In (Dydak and Ruiz del Portal (Monomorphisms and epimorphisms in pro-categories, preprint)) we gave characterizations of monomorphisms (re[...]texto impreso
Gallego Rodrigo, Francisco Javier ; Purnaprajna, Bangere P. ; González Andrés, Miguel | Elsevier Science B.V. (North-Holland) | 2008-05Let Y be a smooth Enriques surface. A K3 carpet on Y is a double structure on Y with the same invariants as a smooth K3 surface (i.e., regular and with trivial canonical sheaf). The surface Y possesses an etale K3 double cover X -> (pi) over bar[...]texto impreso
It is known [J. F. Ritt, Trans. Am. Math. Soc. 23, 51-66 (1922; JFM 48.0079.01), H. T. Engstrom, Am. J. Math. 63, 249–255 (1941; Zbl 0025.10403), H.Levi, ibid. 64, 389–400 (1942; Zbl 0063.03512), F. Dorey and G. Whaples, J. Algebra 28, 88-101 (1[...]texto impreso
Gamboa, J. M. ; Alonso García, María Emilia ; Ruiz Sancho, Jesús María | Elsevier Science B.V. (North-Holland) | 1985It is well-known that if C is an algebraic curve over the real closed field R and is a total ordering of the function field R(C) of C then there is a semi-algebraic embedding w : (0, 1) ! C such that f 2 R(C) is positive with respect to if and[...]texto impreso
A. A. Be?linson's spectral sequence [Funktsional. Anal. i Prilozhen. 12 (1978), no. 3, 68–69;] gives a way of reconstructing any coherent sheaf on P n from the cohomology on P n of this sheaf and its twists. In this article the author shows [...]texto impreso
his work we present a full geometric characterization of the 1-dimensional polynomial and regular images S of Rn and we compute for all of them the invariants ppSq and rpSq, already introduced in [FG2].texto impreso
In this work we analyze some topological properties of the remainder partial derivative M := beta(s)*M\M of the semialgebraic Stone-Cech compactification beta(s)*M of a semialgebraic set M subset of R-m in order to 'distinguish' its points from [...]texto impreso
Let R be a real closed field and n greater than or equal to 2. We prove that: (1) for every finite subset F of R", the semialgebraic set R"\F is a polynomial image of R"; and (2) for any independent linear forms 1, of R", the semialgebraic set {[...]
