In this work, we consider the reformulation of hierarchical (H) matrix algorithms for many-core processors with a model implementation on graphics processing units (GPUs). H matrices approximate specific dense matrices, e.g., from discretized integral equations or kernel ridge regression, leading to log-linear time complexity in dense matrix-vector products. The parallelization of H matrix oper...

An n × n complex matrix A is h-pseudo-tournament if A + A∗ = hh∗ − I, where h is a complex, non-zero column vector. The class of h-pseudo-tournament matrices is a generalization of the well studied tournament-like matrices: h-hypertournament matrices, generalized tournament matrices and tournament matrices. In this paper we derive new spectral properties of an h-pseudo-tournament matrix. When t...

Nonnegative matrix factorization (NMF) is the problem of decomposing a given nonnegative n×m matrix M into a product of a nonnegative n × d matrix W and a nonnegative d ×m matrix H. A longstanding open question, posed by Cohen and Rothblum in 1993, is whether a rational matrix M always has an NMF of minimal inner dimension d whose factors W and H are also rational. We answer this question negat...

Nonnegative matrix factorization (NMF) is the problem of decomposing a given nonnegative n×m matrix M into a product of a nonnegative n× d matrix W and a nonnegative d ×m matrix H . A longstanding open question, posed by Cohen and Rothblum in 1993, is whether a rational matrix M always has an NMF of minimal inner dimension d whose factors W and H are also rational. We answer this question negat...

In this work, we consider the reformulation of hierarchical (H) matrix algorithms for many-core processors with a model implementation on graphics processing units (GPUs). H matrices approximate specific dense matrices, e.g., from discretized integral equations or kernel ridge regression, leading to log-linear time complexity in dense matrix-vector products. The parallelization of H matrix oper...

where 〈·, ·〉 denotes the standard inner product on C. If the Hermitian matrix H is invertible, then the indefinite inner product is nondegenerate. In that case, for every matrix T ∈ C, there is the unique matrix T [∗] satisfying [T x, y] = [x, T y] for all x, y ∈ C, and it is given by T [∗] = HT H . In these spaces, the notion of H-quasihyponormal matrix can be introduced by analogy with the qu...

in-vitro labeling of rbc with 99mtc is an intricate procedure and there is always a need foran alternate blood pool imaging agent. the aim of this study was to prepare an effective nanosized liposome (nls) similar to human rbc for blood pool scintigraphy. this study formulatespeg-nls and non-peg-nls using film method plus high pressure homogenization technique.biodistribution studies were perfo...

H-matrices appear in various areas of science and engineering and it is of vital importance to have an Algorithm to identify the H-matrix character of a certain matrix A ∈ Cn,n. Recently, the present authors have proposed a new iterative criterion (Algorithm AH) to completely identify the H-matrix property of an irreducible matrix. The present work extends the previous Algorithm to cover the re...

It is well-known that a Sylvester Hadamard matrix can be described by means of a cocycle. In this paper it is shown that the additional internal structure in a Sylvester Hadamard matrix, provided by the cocycle, is su cient to guarantee some kind of reduction in the computational complexity of calculating its permanent using Ryser's formula. A Hadamard matrix H of order n is an n× n matrix with...

It is well accepted that the mitochondrial K+/H+ antiporter is regulated by matrix Mg2+; however, this is not the only factor controlling its activity. The precise conditions used to deplete divalent cations have profound effects on the subsequent activity of the antiporter in a KOAc assay medium. Examination of the proton fluxes during both pretreatment and subsequent assay of K+/H+ antiport r...