Ara es mostren els items 21-40 de 86

    • ¿Cuántas raíces de la unidad anulan un polinomio en dos variables? 

      Gualdi, Roberto (Real Sociedad Matemática Española, 2023)
      Article
      Accés obert
      En estas páginas vamos a considerar la tarea de buscar raíces de la unidad que son soluciones de un polinomio en dos variables con coeficientes algebraicos. Esta pregunta, aparentemente inocente, nos llevará por un precioso ...
    • Darboux integrals for Schrödinger planar vector fields via Darboux transformations 

      Acosta Humánez, Primitivo Belén; Pantazi, Chara (2012-07-14)
      Article
      Accés obert
      In this paper we study the Darboux transformations of planar vector fields of Schr odinger type. Using the isogaloisian property of Darboux transformation we prove the \invariance" of the objects of the \Darboux theory ...
    • Degree lower bounds of tower-type for approximating formulas with parity quantifiers 

      Atserias, Albert; Dawar, Anuj (2014-02-01)
      Article
      Accés obert
      Kolaitis and Kopparty have shown that for any first-order formula with parity quantifiers over the language of graphs, there is a family of multivariate polynomials of constant-degree that agree with the formula on all but ...
    • Delegació verificable del càlcul de polinomis 

      Obrador Sureda, Marc (Universitat Politècnica de Catalunya, 2013-02-15)
      Projecte/Treball Final de Carrera
      Accés obert
      [ANGLÈS] Algorithms to delegate the evaluation of some polynomial, private or not, at some point, private or not, to an untrusted entity.
    • Edge-distance-regular graphs 

      Cámara Vallejo, Marc; Dalfó Simó, Cristina; Fàbrega Canudas, José; Fiol Mora, Miquel Àngel; Garriga Valle, Ernest (2011-03-11)
      Report de recerca
      Accés obert
      Edge-distance-regularity is a concept recently introduced by the authors which is similar to that of distance-regularity, but now the graph is seen from each of its edges instead of from its vertices. More precisely, a ...
    • Efficient polynomial delegation under standard assumptions 

      Morillo Bosch, M. Paz; Obrador Sureda, Marc (Institute of Electrical and Electronics Engineers (IEEE), 2013)
      Comunicació de congrés
      Accés restringit per política de l'editorial
      In this paper we present a new scheme for verifiable delegation of polynomials in a cloud computing scenario. The security of our scheme is based on a standard assumption, the subgroup membership one. Furthermore, the ...
    • Enhanced neural network model for regional ionospheric modeling and evaluation under different solar-geomagnetic conditions 

      Dong, Yanfeng; Gao, Chengfa; Long, Fengyang; Nie, Wenfeng; Juan Zornoza, José Miguel; Rovira Garcia, Adrià; Zhang, Ruicheng (2023-03-01)
      Article
      Accés obert
      Monitoring spatiotemporal variations of ionospheric vertical total electron content (VTEC) is crucial for space weather and satellite positioning. In the present study, an enhanced neural network (ENN) model is proposed ...
    • Existence of periodic solutions with nonconstant sign in a class of generalized abel equations 

      Olm Miras, Josep Maria; Ros Oton, Xavier (2013-04)
      Article
      Accés obert
      This article provides sufficient conditions for the existence of periodic solutions with nonconstant sign in a family of polynomial, non-auto-nomous, firrst-order diferential equations that arise as a generalization of the ...
    • Feasible interpolation for polynomial calculus and sums-of-squares 

      Hakoniemi, Tuomas Antero (Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2020)
      Text en actes de congrés
      Accés obert
      We prove that both Polynomial Calculus and Sums-of-Squares proof systems admit a strong form of feasible interpolation property for sets of polynomial equality constraints. Precisely, given two sets P(x, z) and Q(y, z) of ...
    • Feasibly constructive proofs of succinct weak circuit lower bounds 

      Muller, Moritz Martin; Pich, Ján (2020-02)
      Article
      Accés obert
      We ask for feasibly constructive proofs of known circuit lower bounds for explicit functions on bit strings of length n. In 1995 Razborov showed that many can be proved in PV1, a bounded arithmetic formalizing polynomial ...
    • Gale duality bounds on the location of roots of polynomials with nonnegative coefficients 

      Pfeifle, Julián (2010-04)
      Article
      Accés obert
      We bound the location of roots of polynomials that have nonnegative coefficients with respect to a fixed but arbitrary basis of the vector space of polynomials of degree at most d. For this, we interpret the basis polynomials ...
    • Galois: entre els radicals 

      Lario Loyo, Joan Carles (2012-10-03)
      Audiovisual
      Accés obert
    • Genetics of polynomials over local fields 

      Guàrdia Rubies, Jordi; Nart Vinyals, Enric (2015)
      Article
      Accés obert
      Let (K, v) be a discrete valued field with valuation ring O, and let Ov be the completion of O with respect to the v-adic topology. In this paper we discuss the advantages of manipulating polynomials in Ov[x] on a computer ...
    • Grupos de Galois lineales provenientes de la geometría 

      Dieulefait, Luís V. (2013-03-06)
      Audiovisual
      Accés obert
    • Integrability and dynamics of a simplified class B laser system 

      Llibre Saló, Jaume; Pantazi, Chara (American Institute of Physics (AIP), 2023-10-12)
      Article
      Accés obert
      A simplified class B laser system is a family of differential polynomial systems of degree two depending on the parameters a and b. Its rich dynamics has already been observed in 1980s, see Arecchi et al. [Opt. Commun. 51, ...
    • Interpretació analítica d’estratificacions pel polinomi de Bernstein-Sato 

      Morella Giménez, Maria (Universitat Politècnica de Catalunya, 2024-01-19)
      Treball Final de Grau
      Accés obert
      En aquest treball de final de grau ens centrarem en el problema de classificació analítica de branques amb un exponent característic. El nostre objectiu és construir una estratificació per un invariant analític concret: ...
    • Kac's theorem on the number of real roots and its consequences in average complexity 

      Cucker Farkas, Juan Felipe; Roy, Marie-Françoise (1989)
      Report de recerca
      Accés obert
      We recall in this note a theorem of Kac which gives an assymptotic equivalent of the expected number of real roots of a random polynomial, and we get from it some estimations on the average complexity of several algorithms ...
    • Kolmogorov complexity of #P functions 

      Green, Frederic; Torán Romero, Jacobo (1991-01)
      Report de recerca
      Accés obert
      Are the outputs of #P functions "random"? We way phrase this question more precisely: are there #P functions whose outputs cannot in general be compressed into a string of small length, and recovered quickly from that ...
    • Layer structure of De Bruijn and Kautz digraphs: an application to deflection routing 

      Fàbrega Canudas, José; Martí Farré, Jaume; Muñoz López, Francisco Javier (2016-10-17)
      Article
      Accés obert
      In the main part of this paper we present polynomial expressions for the cardinalities of some sets of interest of the nice distance-layer structure of the well-known De Bruijn and Kautz digraphs. More precisely, given a ...
    • Lectura de la memòria sobre la resolubilitat de les equacions per radicals 

      Pla i Carrera, Josep (2013-03-06)
      Audiovisual
      Accés obert