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Matemáticas: Recent submissions

Now showing items 61-80 of 335

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      Composition operators on the weighed Bergman-Nevanlinna classes 

      Sharma, Somdatt D.; Sharma, Ajay K. (Editorial Universidad de Sevilla, 2005)
      In this paper we use an α-Carleson measure and a vanishing Carleson measure to characterize bounded and compact composition operators on weighted Bergman-Nevanlinna spaces.
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      Operators on Lp and the role of the image of the unit ball 

      Romero Moreno, María del Carmen (Editorial Universidad de Sevilla, 2005)
      Let p ∈ [1, +∞] such that its conjugate exponent q is not an even integer and let T be an operator defined on Lp(λ) with ...
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      Composition operators with linear fractional smbols and their adjoints 

      Martín Gómez, María José (Editorial Universidad de Sevilla, 2005)
      We characterize all linear fractional maps of the disk into itself in terms of their coefficients. We also prove the formula ...
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      Toeplitz operators and division by inner functions 

      Girela Álvarez, Daniel; González Enríquez, Cristóbal Miguel; Peláez Márquez, José Ángel (Editorial Universidad de Sevilla, 2005)
      A subspace X of the Hardy space H1 is said to have the K-property if for any ψ ∈ H∞, the Toeplitz operator Tψ maps X into ...
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      Banach algebras with trivial cohomology 

      El Harti, Rachid (Editorial Universidad de Sevilla, 2005)
      A plausible conjecture is that Banach algebras with trivial cohomology have to be semisimple and finite dimensional. In ...
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      A parametrization for the symbols of a Hankel type operator 

      Bermudo Navarrete, Sergio; Marcantognini, Stefania A. M.; Morán, María Dolores (Editorial Universidad de Sevilla, 2005)
      Hankel operators and their symbols, as generalized by V. Pták and P. Vrbová, are considered. In this more general framework, ...
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      Volterra operators on spaces of analytic functions - a survey 

      Siskakis, Aristomenis (Editorial Universidad de Sevilla, 2005)
      We give a short and selective account of results known about operators of the form Vg(f)(z) = 1/z Z z 0 f(ζ)g0 (ζ) dζ, where g is analytic on the disc and the operator Tg = zVg acts on spaces of analytic functions.
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      Invariant subspaces of translation semigroups 

      Power, Stephen C. (Editorial Universidad de Sevilla, 2005)
      In these lectures I shall give an account of some recent results and open problems relating to subspaces of square integrable ...
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      How large is a Riemann surface: the type problem 

      Drasin, David (Editorial Universidad de Sevilla, 2005)
      The uniformization theorem asserts that a simply-connected non-compact Riemann surface S is conformally equivalent to ...
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      Analytic contractions and boundary behaviour - an overview 

      Aleman, Alexandru; Richter, Stefan; Sundberg, Carl (Editorial Universidad de Sevilla, 2005)
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      Flips in combinatorial pointed pseudo-triangulations with face degree at most four 

      Aichholzer, Oswin; Hackl, Thomas; Orden Martín, David; Pilz, Alexander; Saumell Mendiola, María; Vogtenhuber, Birgit (2013)
      In this paper we consider the flip operation for combinatorial pointed pseudo-triangulations where faces have size 3 or ...
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      Monotone crossing number of complete graphs 

      Balko, Martin; Fulek, Radoslav; Kynčl, Jan (2013)
      In 1958, Hill conjectured that the minimum number of crossings in a drawing of Kn is exactly Z(n) = 1/4 n-1/2/2 n−2/2 ...
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      On 4-connected geometric graphs 

      García Olaverri, Alfredo; Huemer, Clemens; Tejel Altarriba, Francisco Javier; Valtr, Pavel (2013)
      Given a set S of n points in the plane, in this paper we give a necessary and sometimes sufficient condition to build a 4-connected non-crossing geometric graph on S.
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      Phase transitions in the Ramsey-Turán theory 

      Balogh, József (2013)
      Let f(n) be a function and L be a graph. Denote by RT(n, L, f(n)) the maximum number of edges of an L-free graph on n ...
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      The alternating path problem revisited 

      Claverol Aguas, Mercè; Garijo Royo, Delia; Hurtado Díaz, Ferran; Lara Cuevas, María Dolores; Seara Ojea, Carlos (2013)
      It is well known that, given n red points and n blue points on a circle, it is not always possible to find a plane geometric ...
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      Witness bar visibility 

      Cortés Parejo, María del Carmen; Hurtado Díaz, Ferran; Márquez Pérez, Alberto; Valenzuela Muñoz, Jesús (2013)
      Bar visibility graphs were introduced in the seventies as a model for some VLSI layout problems. They have been also studied ...
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      On making a graph crossing-critical 

      Hernández Vélez, César Israel; Leaños Macías, Jesús (2013)
      A graph is crossing-critical if its crossing number decreases when we remove any of its edges. Recently it was proved that ...
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      On three parameters of invisibility graphs 

      Cibulka, Josef; Korbelář, Miroslav; Kynčl, Jan; Mészáros, Viola; Stolař, Rudolf; Valtr, Pavel (2013)
      The invisibility graph I(X) of a set X ⊆ Rd is a (possibly infinite) graph whose vertices are the points of X and two ...
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      Improved enumeration of simple topological graphs 

      Kynčl, Jan (2013)
      A simple topological graph T = (V (T ), E(T )) is a drawing of a graph in the plane where every two edges have at most one ...