Browsing by Subject "Matrices"
Now showing items 120 of 148

A canonical reduced form for singular time invariant linear systems
(200909)
Conference report
Open AccessWe consider quadruples of matrices (E; A;B;C), representing singular linear time invariant systems in the form Ex_ (t) = Ax + Bu y = Cx ¾ (1) with E;A 2 Mp£n(C), B 2 Mp£m(C) and C 2 Mq£n(C) under proportional and ... 
A construction of small regular bipartite graphs of girth 8
(200901)
Article
Open AccessLet q be a prime a power and k an integer such that 3 ≤ k ≤ q. In this paper we present a method using Latin squares to construct adjacency matrices of kregular bipartite graphs of girth 8 on $2(kq^{2}q)$ vertices. Some ... 
A design procedure for overlapped guaranteed cost controllers
(Elsevier, 2008)
Conference lecture
Open AccessIn this paper a quadratic guaranteed cost control problem for a class of linear continuoustime statedelay systems with normbounded uncertainties is considered. We will suppose that the systems are composed by two ... 
A geometric approach to the Carlson problem
(Society for Industrial and Applied Mathematics (Filadèlfia), 2000)
Article
Open AccessThe possible observability indices of an observable pair of matrices, when supplementary subpairs are prescribed, are characterized when the “quotient” one is nilpotent. The geometric techniques used are also valid in the ... 
A matrix derivation of a representation theorem for (trAp)1/p
(Universitat Politècnica de Catalunya. Centre de Càlcul, 1989)
Article
Open AccessA matrix derivation of a wellknown representation theorem for (tr Ap)1/p is given, which is the solution of a restricted maximization problem. The paper further gives a solution of the corresponding restricted minimization ... 
A matrix function useful in the estimation of linear continuoustime models.
(Institut d'Estadística de Catalunya, 2006)
Article
Open AccessIn a recent publication Chen & Zadrozny (2001) derive some equations for efficiently computing eA and ∇ eA, its derivative. They employ an expression due to Bellman (1960), Snider (1964) and Wilcox (1967) for the differential ... 
A new approach to the spectral excess theorem for distanceregular graphs
(20090401)
Article
Open AccessThe Spectral Excess Theorem provides a quasispectral characterization for a (regular) graph $\Gamma$ with $d+1$ different eigenvalues to be distanceregular graph, in terms of the mean (d1)excess of its vertices.\ The ... 
A new method for computing the largest singular value and an associated right singular vector of a complex matrix
(20230928)
Research report
Open AccessA new method for computing the largest singular value \xi_1 and an associated right singular vector of a large and sparse complex matrix A is developed. The method accelerates a new method for computing \xi_1 and an ... 
A new proof of the MillikenAkdeniz theorem
(Universitat Politècnica de Catalunya. Centre de Càlcul, 1989)
Article
Open AccessA simple proof is given for a theorem by Milliken and Akdeniz (1977) about the difference of the MoorePenrose inverses of two positive semidefinite matrices. 
A Stein matrix equation related to transfer matrix of linear dynamic systems over commutative rings
(Editorial de la Universitat Politècnica de València (UPV), 2010)
Conference report
Open AccessEste trabajo está inmerso en el campo de la Teoría de Control sobre un anillo conmutativo R con elemento unidad. Dado un sistema dinámico lineal invariante en el tiempo representado por x+(t) = Ax(t) + Bu(t) sobre R, ... 
A study of QR decomposition and Kalman filter implementations
(Universitat Politècnica de Catalunya, 201409)
Master thesis (preBologna period)
Open Access
Covenantee: Kungliga Tekniska högskolan[ANGLÈS] With the rapid development of new technologies during the last decades, the demand of complex algorithms to work in realtime applications has increased considerably. To achieve the real time expectations and to ... 
A survey on the missing Moore graph
(Elsevier, 2019)
Article
Open AccessThis is a survey on some known properties of the possible Moore graph (or graphs) ¿ with degree 57 and diameter 2. Moreover, we give some new results about it, such as the following. When we consider the distance partition ... 
A variational solution of the timedependent Schrodinger equation by a restricted superposition of frozen Gaussian wavepackets
(200505)
Article
Restricted access  publisher's policyWe present a variational solution of the timedependent Schrodinger equation formed from a restricted superposition of frozen Gaussian wavepackets. The trial function is comprised of a set of frozen Gaussian wavepackets ... 
A Volume Visualization Algorithm using a coherent Extended Weight Matrix
(199501)
Article
Restricted access  publisher's policyDirect celltocell volume visualization algorithms, also called projective rendering methods, present the advantage of allowing semitransparencies and, additionally, as they project all the samples, they avoid the ... 
Adjacency matrices of polarity graphs and of other C4free graphs of large size
(2010)
Article
Restricted access  publisher's policyIn this paper we give a method for obtaining the adjacency matrix of a simple polarity graph $G_q$ from a projective plane PG(2,q), where q is a prime power. Denote by ex(n;C₄) the maximum number of edges of a graph on n ... 
Ajuste temporal de matrices OD basado en una aproximación del gradiente
(Universitat Politècnica de Catalunya, 201302)
Master thesis
Open AccessModelar la demanda del transporte en función de una matriz OrigenDestino (OD) es un aspecto clave en casi todos los modelos de transporte. Cuando realizamos una planificación estratégica del transporte hacemos uso de ... 
Alternative tests for functional and pointwise outputcontrollability of linear timeinvariant systems
(2013)
Article
Open AccessThis paper deals with the description of a new method for calculating the functional outputcontrollability. It is computed by means of the rank of a certain constant matrix which can be associated to the system. Moreover, ... 
An Eigenvector pattern arising in non linear regression
(Universitat Politècnica de Catalunya. Centre de Càlcul, 1990)
Article
Open AccessLet A = (aij) be an n x n matrix defined by aij = aji = i, i = 1,...,n. This paper gives some elementary properties of A and other related matrices. The eigenstructure of A is conjectured: given an eigenvector v of A the ... 
An iterative linear matrix inequality controllerdesign strategy for Hinfinity structural vibration control
(CRC Press/Balkema, 2019)
Conference report
Open AccessIn this paper, we present a novel Iterative Linear Inequality (ILMI) strategy for controller design that makes it possible to compute suboptimal Hinfinity static outputfeedback (SOF) controllers with highperformance ... 
An open set of 4×4 embeddable matrices whose principal logarithm is not a Markov generator
(Taylor & Francis, 20201217)
Article
Open AccessA Markov matrix is embeddable if it can represent a homogeneous continuoustime Markov process. It is well known that if a Markov matrix has real and pairwisedifferent eigenvalues, then the embeddability can be determined ...