HIV (Human Immunodeficiency Virus) researchers are often concerned with the correlation between plasma viral loads and a covariate, or the correlation between viral load levels from two reservoirs or from two competing quantification assays. Due to the lower limit of detection (LOD) of such...

The main powerful method for establishing termination of term rewriting systems was discovered by Nachum Dershowitz through the introduction of certain natural well founded orderings (lexicographic path orderings). This leads to natural decision problems which may be of the highest computational...

The harmonic Arnoldi method can be used to compute some eigenpairs of a large matrix, and it is more suitable for finding interior eigenpairs. However, the harmonic Ritz vectors obtained by the method may converge erratically and may even fail to converge, so that resulting algorithms may not...

We investigate a class of matrices, called the extended triangular matrices. If a simple condition holds, the inverse of an extended triangular matrix is also an extended triangular matrix. A general form of the characteristic polynomial of a subclass of the extended triangular matrices is also...

We present two cubature formulas on triangle, one having equals coefficients and the other having as nodes the vertex of triangle. The first formula is obtained starting by an approximation formula on triangle and the second formula by using product of two quadrature formulas with multiple nodes

We consider the linear parabolic equation describing the transport of a contaminant in a porous media crossed by a net of infmitly thin fractures. The permeability is very high in the fractures but very low in the porous blocks. We derive the homogenized model corresponding to a net of infmitly...

A of a graph consists of a linear ordering of the vertices along a line in 3-space (the ), and an assignment of edges to half-planes with the spine as boundary (the ), so that edges assigned to the same page can be drawn on that page without crossings. Given a graph = (), let : → ℕ be a...

In Aslyan [1] the representability of arithmetical predicates by means of general form recursive equations is proved. Here we show that arbitrary hyperarithmetical predicate (, …, ) is representable by the system of recursive equations. On the other hand it is shown that the class of...

By the use of Perron-Frobenius theory, simple proofs are given of the Fundamental Theorem of Demography and of a theorem of Cushing and Yicang on the net reproductive rate occurring in matrix models of population dynamics. The latter result, which is closely related to the Stein-Rosenberg...