The Drazin inverse through the matrix pencil approach and its application to the study of generalized linear systems with rectangular or square coefficient matrices.
The equation and the dimension of *congruence orbits.
The fundamental cone and the Minkowski cone.
The Indecomposable Representations of the Dihedral 2-Groups.
The Jordan forms of and .
The linear independence of sets of two and three canonical algebraic curvature tensors.
The Moore-Penrose inverse of a partitioned matrix
The rational canonical form of a matrix.
The Similarity Reduction of Matrices over a Skew Field.
The Smith normal form of product distance matrices
Let G = (V, E) be a connected graph with 2-connected blocks H1, H2, . . . , Hr. Motivated by the exponential distance matrix, Bapat and Sivasubramanian in [4] defined its product distance matrix DG and showed that det DG only depends on det DHi for 1 ≤ i ≤ r and not on the manner in which its blocks are connected. In this work, when distances are symmetric, we generalize this result to the Smith Normal Form of DG and give an explicit formula for the invariant factors of DG.
The theory of beta transformation matrices
Total Reduction of Linear Systems of Operator Equations With the System Matrix in the Companion Form
Two applications of a bound on the Hadamard product with a Cauchy matrix.
Two models for contraction operators. (Deux modèles pour les opérateurs de contraction.)
Über die Konstruktion der Jordanschen Normalform.
Unas notas sobre regularidad en matrices estocásticas.
Let P be a stochastic matrix. We give a necessary and sufficient condition for the existence of the limt -> ∞ ppt from which follows the classical regularity conditions. Another regularity condition based in the Banach point fix theorem is also given.
Unique decomposition for a polynomial of low rank
Let F be a homogeneous polynomial of degree d in m + 1 variables defined over an algebraically closed field of characteristic 0 and suppose that F belongs to the sth secant variety of the d-uple Veronese embedding of into but that its minimal decomposition as a sum of dth powers of linear forms requires more than s summands. We show that if s ≤ d then F can be uniquely written as , where are linear forms with t ≤ (d-1)/2, and Q is a binary form such that with ’s linear forms and ’s forms...
Unitary similarity of algebras generated by pairs of orthoprojectors.
Unitary similarity of projectors.
Universal bounds for positive matrix semigroups
We show that any compact semigroup of positive n × n matrices is similar (via a positive diagonal similarity) to a semigroup bounded by √n. We give examples to show this bound is best possible. We also consider the effect of additional conditions on the semigroup and obtain improved bounds in some cases.