All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 6 Next

Displaying 101 – 120 of 455

Showing per page

A modified Cayley transform for the discretized Navier-Stokes equations

K. A. Cliffe, T. J. Garratt, Alastair Spence (1993)

Applications of Mathematics

This paper is concerned with the problem of computing a small number of eigenvalues of large sparse generalized eigenvalue problems. The matrices arise from mixed finite element discretizations of time dependent equations modelling viscous incompressible flow. The eigenvalues of importance are those with smallest real part and are used to determine the linearized stability of steady states, and could be used in a scheme to detect Hopf bifurcations. We introduce a modified Cayley transform of the...

A multiplication theorem for two-variable positive real matrices

Fazlollah M. Reza (1985)

Aplikace matematiky

A multiplication-division theorem is derived for the positive real functions of two complex variables. The theorem is generalized to encompass the product of positive real functions of two complex variables. The theorem is generalized to encompass the product of positive real matrices whose elements are functions of two complex variables. PRF and PR matrices occur frequantly in the study of electrical multiports and multivariable systems (such as digital filters).

A new characterization of generalized complementary basic matrices

Miroslav Fiedler, Frank J. Hall (2014)

Special Matrices

In this paper, a new characterization of previously studied generalized complementary basic matrices is obtained. It is in terms of ranks and structure ranks of submatrices defined by certain diagonal positions. The results concern both the irreducible and general cases.

A New Characterization of Generalized Complementary Basic Matrices

Miroslav Fiedler, Frank J. Hall (2014)

Special Matrices

In this paper, a new characterization of previously studied generalized complementary basic matrices is obtained. It is in terms of ranks and structure ranks of submatrices defined by certain diagonal positions. The results concern both the irreducible and general cases

A new family of spectrally arbitrary ray patterns

Yinzhen Mei, Yubin Gao, Yan Ling Shao, Peng Wang (2016)

Czechoslovak Mathematical Journal

An n × n ray pattern 𝒜 is called a spectrally arbitrary ray pattern if the complex matrices in Q ( 𝒜 ) give rise to all possible complex polynomials of degree n . In a paper of Mei, Gao, Shao, and Wang (2014) was proved that the minimum number of nonzeros in an n × n irreducible spectrally arbitrary ray pattern is 3 n - 1 . In this paper, we introduce a new family of spectrally arbitrary ray patterns of order n with exactly 3 n - 1 nonzeros.

A new inclusion interval for the real eigenvalues of real matrices

Yinghua Wang, Xinnian Song, Lei Gao (2023)

Czechoslovak Mathematical Journal

By properties of Cvetković-Kostić-Varga-type (or, for short, CKV-type) B-matrices, a new class of nonsingular matrices called CKV-type B ¯ -matrices is given, and a new inclusion interval of the real eigenvalues of real matrices is presented. It is shown that the new inclusion interval is sharper than those provided by J. M. Peña (2003), and by H. B. Li et al. (2007). We also propose a direct algorithm for computing the new inclusion interval. Numerical examples are included to illustrate the effectiveness...

A new look at totally positive matrices

Miroslav Fiedler (2016)

Czechoslovak Mathematical Journal

A close relationship between the class of totally positive matrices and anti-Monge matrices is used for suggesting a new direction for investigating totally positive matrices. Some questions are posed and a partial answer in the case of Vandermonde-like matrices is given.

Currently displaying 101 – 120 of 455