Browsing by Subject "Àlgebra lineal"
Now showing items 120 of 108

A case for malleable threadlevel linear algebra libraries: The LU factorization with partial pivoting
(Institute of Electrical and Electronics Engineers (IEEE), 20190131)
Article
Open AccessWe propose two novel techniques for overcoming loadimbalance encountered when implementing socalled lookahead mechanisms in relevant dense matrix factorizations for the solution of linear systems. Both techniques target ... 
A crosslayer review of deep learning frameworks to ease their optimization and reuse
(Institute of Electrical and Electronics Engineers (IEEE), 2020)
Conference report
Open AccessMachine learning and especially Deep Learning (DL) approaches are at the heart of many domains, from computer vision and speech processing to predicting trajectories in autonomous driving and data science. Those approaches ... 
A general method to obtain the spectrum and local spectra of a graph from its regular partitions
(20200712)
Article
Open AccessIt is well known that, in general, part of the spectrum of a graph can be obtained from the adjacency matrix of its quotient graph given by a regular partition. In this paper, a method that gives all the spectrum, and also ... 
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 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 note on symplectic and Poisson linearization of semisimple Lie algebra actions
(201503)
External research report
Open AccessIn this note we prove that an analytic symplectic action of a semisimple Lie algebra can be locally linearized in Darboux coordinates. This result yields simultaneous analytic linearization for Hamiltonian vector fields ... 
A recursion formula for expected negative and positive powers of the central Wishart distribution
(Institut d'Estadística de Catalunya, 2007)
Article
Open AccessWe use Haff’s fundamental identity to express the expectation of Sp in lowerorder terms, where S follows the central Wishart distribution. 
A simple proof of the spectral excess theorem for distanceregular graphs
(Elsevier, 20100415)
Article
Restricted access  publisher's policyThe spectral excess theorem provides a quasispectral characterization for a (regular) graph Γ with d+1 distinct eigenvalues to be distanceregular graph, in terms of the excess (number of vertices at distance d) of each ... 
Algebra lineal
(Edicions UPC, 2002)
Book
Restricted access to UB, UAB, UPC, UPF, UdG, UdL, URV, UOC, BC, UVic, UJI, URL, UIC usersAquest text aborda els temes fonamentals de l'Àlgebra Lineal que formen part dels continguts de primer curs de les carreres d'Enginyeria i Ciències: aplicacions lineals, matrius, determinants, diagonalització, producte ... 
Aligning modeled and observed behavior: A compromise between computation complexity and quality
(Springer, 2017)
Conference report
Open AccessCertifying that a process model is aligned with the real process executions is perhaps the most desired feature a process model may have: aligned process models are crucial for organizations, since strategic decisions can ... 
An alternative collection of structural invariants for matrix pencils under strict equivalence
(WSEAS Press. World Scientific and Engineering Academy and Society, 2009)
Article
Restricted access  publisher's policyWe consider pairs of matrices (E;A), representing singular linear time invariant sys tems in the form Ex_ (t) = Ax with E;A 2 Mp£n(C) under restricted equivalence. In this paper we obtain an alternative collection of ... 
An alternative complete system of invariants for matrix pencils under strict equivalence
(WSEAS Press. World Scientific and Engineering Academy and Society, 200912)
Part of book or chapter of book
Restricted access  publisher's policyWe consider triples of matrices (E; A;B), representing singular linear time invariant systems in the form Ex_ (t) = Ax(t) + Bu(t), with E;A 2 Mp£n(C) and B 2 Mn£m(C), un der proportional and derivative feedback. Using ... 
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 ... 
Analizing exact controllability of lorder linear systems
(WSEAS Press, 20170101)
Article
Open AccessIn recent years there has been growing interest in the descriptive analysis of lorder time invariant linear dynamical system xl = Al1xl1 ++ A0x0 where Ai are square complex matrices and xi denotes the ith derivative ... 
Analyzing control properties of multiagent linear systems
(20200930)
Article
Open AccessThe networked multiagent systems that they are interconnected via communication channels have great applicability in multiple areas, such as power grids, bioinformatics, sensor networks, vehicles, robotics and neuroscience, ... 
Aplicacions lineals, diagonalització i vectors propis. Contextualització i objectius per a la ciència de dades
(Fundació per a la Universitat Oberta de Catalunya, 201902)
Part of book or chapter of book
Restricted access  publisher's policy 
Aplicacions lineals, diagonalització i vectors propis. Problemes per a la ciència de dades
(Fundació per a la Universitat Oberta de Catalunya, 201902)
Part of book or chapter of book
Restricted access  publisher's policy 
Application of the multilevel decomposition algorithm to the frequency analysis of large microstrip antenna arrays
(IEEEINST ELECTRICAL ELECTRONICS ENGINEERS INC, 20020331)
Article
Open AccessThe application of integral equation methods based in the method of moments discretization to solve large antenna arrays is difficult due to the fact that the computational requirements increase rapidly with the number ...