Browsing by Author "Ventura Capell, Enric"Més informacióMés informació

Now showing items 1-20 of 55

    • A description of auto-fixed subgroups in a free group 

      Martino, Armando; Ventura Capell, Enric (2004-06)
      Article
      Open Access
      Let F be a finitely generated free group. By using Bestvina-Handel theory, as well as some further improvements, the eigengroups of a given automorphism of F (and its fixed subgroup among them) are globally analyzed and ...

    • A recursive presentation for Mihailova's subgroup 

      Bogopolski, Oleg; Ventura Capell, Enric (2010)
      Article
      Open Access
      We give an explicit recursive presentation for Mihailova's sub- group M(H) of Fn Fn corresponding to a nite, concise and Pei er aspherical presentation H = hx1; : : : ; xn jR1; : : : ;Rmi. This partially answers a ...

    • A Whitehad algorithm for toral relatively hyperbolic groups 

      Kharlampovich, Olga; Ventura Capell, Enric (2012-12-04)
      Article
      Open Access
      The Whitehead problem is solved in the class of toral relatively hyperbolic groups G (i.e. torsion-free relatively hyperbolic groups with abelian parabolic subgroups): there is an algorithm which, given two nite ...

    • Absolute type shaft encoding using LFSR sequences with prescribed length 

      Fuertes Armengol, José Mª; Balle, Borja; Ventura Capell, Enric (2006-02)
      Article
      Open Access
      Maximal-length binary sequences have been known for a long time. They have many interesting properties, one of them is that when taken in blocks of n consecutive positions they form 2 n ° 1 diÆerent codes in a ...

    • Absolute-type shaft encoding using LFSR sequences with a prescribed length 

      Fuertes Armengol, José Mª; Balle Pigem, Borja de; Ventura Capell, Enric (2008-03-31)
      Article
      Open Access
      Maximal-length binary sequences have existed for a long time. They have many interesting properties, and one of them is that, when taken in blocks of n consecutive positions, they form 2n - 1 different codes in a closed ...

    • Algorithmic problems for free-abelian times free groups 

      Delgado Rodríguez, Jordi; Ventura Capell, Enric (2013-10-01)
      Article
      Open Access
      We study direct products of free-abelian and free groups with special emphasis on algorithmic problems. After giving natural extensions of standard notions into that family, we find an explicit expression for an arbitrary ...

    • Algorithmic recognition of infinite cyclic extensions 

      Cavallo, Bren; Delgado Rodríguez, Jordi; Kahrobaei, Delaram; Ventura Capell, Enric (2016-10-25)
      Article
      Open Access
      We prove that one cannot algorithmically decide whether a finitely presented Z-extension admits a finitely generated base group, and we use this fact to prove the undecidability of the BNS invariant. Furthermore, we show ...

    • An algorithm to design prescribed length codes for single-tracked shaft encoders 

      Balle Pigem, Borja de; Ventura Capell, Enric; Fuertes Armengol, José Mª (2009-04-14)
      Conference report
      Open Access
      Abstract-Maximal-length binary shift register sequences have been known for a long time. They have many interesting properties, one of them is that when taken in blocks of n consecutive positions they form 2n - 1 different ...

    • ÀLGEBRA (Examen 1r quadrimestre) 

      Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2005-11-25)
      Exam
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    • ÀLGEBRA (Examen 1r quadrimestre) 

      Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2006-01-13)
      Exam
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    • Bounding the gap between a free group (outer) automorphism and its inverse 

      Ladra, Manuel; Silva, Pedro V.; Ventura Capell, Enric (2016-09-01)
      Article
      Open Access
      For any finitely generated group GG , two complexity functions aGaG and ßGßG are defined to measure the maximal possible gap between the norm of an automorphism (respectively, outer automorphism) of GG and the norm ...

    • CÀLCUL (Examen 1r quadrim.) 

      Domènech Blázquez, Margarita; Puente del Campo, María Albina; Rubió Díaz, Pedro; Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2006-01-15)
      Exam
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    • CÀLCUL (Examen 1r quadrim.) 

      Domènech Blázquez, Margarita; Puente del Campo, María Albina; Rubió Díaz, Pedro; Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2006-01-15)
      Exam
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    • CÀLCUL (Examen 1r quadrim.) 

      Domènech Blázquez, Margarita; Puente del Campo, María Albina; Rubió Díaz, Pedro; Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2006-01-15)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric; Pons Vallès, Montserrat (Universitat Politècnica de Catalunya, 2001-01-15)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric; Pons Vallès, Montserrat (Universitat Politècnica de Catalunya, 2000-11-06)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric; Pons Vallès, Montserrat (Universitat Politècnica de Catalunya, 2004-01-12)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2008-12-22)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric; Pons Vallès, Montserrat (Universitat Politècnica de Catalunya, 1996-11-14)
      Exam
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    • CÀLCUL 1 (Examen 1r quadrim) 

      Ventura Capell, Enric (Universitat Politècnica de Catalunya, 2008-11-14)
      Exam
      Restricted access to the UPC academic community