Now showing items 1-20 of 50

  • A formula for the Kirchhoff index 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2007-09-30)
    Article
    Open Access
    We show here that the Kirchhoff index of a network is the average of the Wiener capacities of its vertices. Moreover, we obtain a closed-form formula for the effective resistance between any pair of vertices when the ...
  • Application of the forces' method in dynamic systems 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2007-10-11)
    Article
    Open Access
    We present here some applications of the Forces's method in dynamic systems. In particular, we consider the problem of the approximation of the trajectories of a conservative system of point masses by means of the minimization ...
  • Boundary value problems for Schrödinger operators on a path 

    Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gago Álvarez, Silvia (2012-05-25)
    External research report
    Open Access
    In this work, we concentrate on determining explicit expressions, via suitable orthogonal polynomials on the line, for the Green function associated with any regular boundary value problem on a weighted path, whose weights ...
  • Boundary value problems for Schrödinger operators on a Path Associated to Orthogonal Polynomials 

    Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gago Álvarez, Silvia (Springer, 2013)
    Part of book or chapter of book
    Restricted access - publisher's policy
    In this work, we concentrate on determining explicit expressions, via suitable orthogonal polynomials on the line, for the Green function associated with any regular boundary value problem on a weighted path, whose weights ...
  • Bounds on the first non-null eigenvalue for self-adjoint boundary value problems on networks 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2006-09)
    Article
    Open Access
    We aim here at obtaining bounds on the first non-null eigenvalue for self-adjoint boundary value problems on a weighted network by means of equilibrium measures, that includes the study of Dirichlet, Neumann and Mixed ...
  • Cálculo : problemas y soluciones 

    Estela Carbonell, M. Rosa; Cuello Nebot, Eva; Carmona Mejías, Ángeles (Edicions UPC, 2002)
    Book
    Open Access
    Los problemas contenidos en el libro que se presenta son el resultado de cuatro años de docencia en la asignatura Cálcul I de la ETSECCPB. En ellos se desarrolla el cálculo diferencial e integral de una y varias variables, ...
  • Cálculo : problemas y soluciones 

    Estela Carbonell, M. Rosa; Cuello Nebot, Eva; Carmona Mejías, Ángeles (Edicions UPC, 2000)
    Book
    Open Access
    Los problemas contenidos en el libro que se presenta son el resultado de cuatro años de docencia en la asignatura Cálcul I de la ETSECCPB. En ellos se desarrolla el cálculo diferencial e integral de una y varias variables, ...
  • Càlcul : problemes i solucions 

    Estela Carbonell, M. Rosa; Cuello Nebot, Eva; Carmona Mejías, Ángeles (Edicions UPC, 2008)
    Book
    Open Access
    Els problemes que aquest llibre conté són el resultat d'alguns anys de docència en l'assignatura Càlcul de les titulacions d'Enginyeria de Camins, Canals i Ports, i d'Enginyeria Geològica, i desenvolupen el càlcul diferencial ...
  • Characterization of symmetric M-matrices as resistive inverses 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2007-01-25)
    Article
    Open Access
    We aim here at characterizing those nonnegative matrices whose inverse is an irreducible Stieltjes matrix. Specifically, we prove that any irreducible Stieltjes matrix is a resistive inverse. To do that we consider the ...
  • Computational cost of the Fekete problem 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2007-10-11)
    Article
    Open Access
    We present here strong numerical and statistical evidence of the fact that the Smale's 7th problem can be answered affirmatively. In particular, we show that a local minimum for the logarithmic potential energy in the ...
  • Desde un biberón hasta una catedral 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos (2010)
    Conference lecture
    Open Access
  • Dirichlet-to-Robin maps on finite networks 

    Arauz Lombardía, Cristina; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos (2015-04-01)
    Article
    Open Access
    Our aim is to characterize those matrices that are the response matrix of a semi positive definite Schrodinger operator on a circular planar network. Our findings generalize the known results and allow us to consider both ...
  • Dirichlet-to-Robin matrix on networks 

    Arauz Lombardia, Cristina; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos (2014)
    Article
    Open Access
    In this work, we de ne the Dirichlet{to{Robin matrix associated with a Schr odinger type matrix on general networks, and we prove that it satis es the alternating property which is essential to characterize those matrices ...
  • Discrete inverse problem on grids 

    Arauz Lombardia, Cristina; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos (2016)
    Conference report
    Open Access
    In this work, we present an algorithm to the recovery of the conductance of a n –dimensional grid. The algorithm is based in the solution of some overdetermined partial boundary value problems defined on the grid; that is, ...
  • Discrete Serrin's problem 

    Arauz Lombardía, Cristina; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos (Elsevier, 2015-03-01)
    Article
    Open Access
    We consider here the discrete analogue of Serrin's problem: if the equilibrium measure of a network with boundary satisfies that its normal derivative is constant, what can be said about the structure of the network and ...
  • Effective resistances and Kirchhoff index in subdivision networks 

    Carmona Mejías, Ángeles; Monsó Burgués, Enrique P.J.; Mitjana Riera, Margarida (2016)
    Conference report
    Restricted access - publisher's policy
    In this work we compute the effective resistances and the Kirchhoff Index of subdivision networks in terms of the corresponding parameters of the original network. Our techniques are based on the study of discrete operators ...
  • Effective resistances and Kirchhoff index in subdivision networks 

    Carmona Mejías, Ángeles; Mitjana Riera, Margarida; Monsó Burgués, Enrique P.J. (Taylor & Francis, 2016-11-12)
    Article
    Open Access
    We define a subdivision network ¿S of a given network ¿; by inserting a new vertex in every edge, so that each edge is replaced by two new edges with conductances that fulfill electrical conditions on the new network. In ...
  • Equilibrium measures on finite networks. Effective resistance and hitting time 

    Carmona Mejías, Ángeles; Bendito Pérez, Enrique; Encinas Bachiller, Andrés Marcos (2001)
    Article
    Open Access
    We aim here at showing how the equilibrium measures for a finite network can be used to obtain simple expressions for both Green and Poisson kernels and hence we can deduce nice expressions of the hitting time and the ...
  • Estimation of Fekete points 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2005-05)
    Article
    Open Access
    In this paper we present a new method to estimate Fekete points on surfaces. Although our method works in a general setting, we concentrate on its application to the unit sphere because it is the prototype problem and ...
  • Fekete points in non-smooth surfaces 

    Bendito Pérez, Enrique; Carmona Mejías, Ángeles; Encinas Bachiller, Andrés Marcos; Gesto Beiroa, José Manuel (2006-07)
    Article
    Open Access
    In this paper we present a procedure for the estimation of the Fekete points on a wide variety of non-regular objects in $R^3$. We understand the problem of the Fekete points in terms of the identification of good ...