Results 21 to 30 of about 45,774 (276)
Applied Water Science, 2017 The assessment of groundwater quality is an obligatory pre-requisite to developing countries like India with rural-based economy. Heavy metal concentration in groundwater from Besant Nagar to Sathankuppam, South Chennai was analyzed to assess the ...
S. G. D. Sridhar +6 more
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MATRICES TOTALLY POSITIVE RELATIVE TO A TREE [PDF]
, 2009 It is known that for a totally positive (TP) matrix, the eigenvalues are positive and distinct and the eigenvector associated with the smallest eigenvalue is totally nonzero and has an alternating sign pattern.
Johnson,, Charles R. +8 more
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Arrangements of equal minors in the positive Grassmannian [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 We discuss arrangements of equal minors in totally positive matrices. More precisely, we would like to investigate the structure of possible equalities and inequalities between the minors.
Miriam Farber, Alexander Postnikov
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Isospectral matrix flow maintaining staircase structure and total positivity of an initial matrix
Linear Algebra and its Applications, 2017 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Moghaddam, Mahsa R. +2 more
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Seasonal variations in high time-resolved chemical compositions, sources, and evolution of atmospheric submicron aerosols in the megacity Beijing [PDF]
Atmospheric Chemistry and Physics, 2017 A severe regional haze problem in the megacity Beijing and surrounding areas, caused by fast formation and growth of fine particles, has attracted much attention in recent years.
W. Hu +9 more
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Square matrices with the inverse diagonal property
Kuwait Journal of ScienceWe identify the class of real square invertible matrices A for which the signs of the diagonal entries of A−1 match those of A, and begin their study. We say such matrices have the inverse diagonal property (IDP).
Susana Furtado +3 more
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Source Apportionment of One-Hour Semi-Continuous Data Using Positive Matrix Factorization with Total Mass (Nonvolatile plus Semi-Volatile) Measured by the R&P FDMS Monitor [PDF]
Aerosol Science and Technology, 2008 Positive matrix factorization (PMF) was used to elucidate sources of fine particulate material (PM 2.5 ) for a study conducted during July 2003 in Rubidoux, CA. One-h averaged semi-continuous measurements were made with a suite of instruments to provide PM 2.5 mass and chemical composition data.
Brett D. Grover, Delbert J. Eatough
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Totally positive matrices and totally positive hypergraphs
, 2001 A real matrix is totally positive if all its minors are nonnegative. In this paper, we characterize 0–1 matrices that can be transformed into totally positive matrices by permutations of rows and ...
Lehel, Jenő +2 more
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AxiomsThe approach to solving linear systems with structured matrices by means of the bidiagonal factorization of the inverse of the coefficient matrix is first considered in this review article, the starting point being the classical Björck–Pereyra algorithms
José-Javier Martínez
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Total positivity, spherical series, and hypergeometric functions of matrix argument
Journal of Approximation Theory, 1989 The paper is concerned with establishing the total positivity of a real function \(K(x,y)=f(xy)\), where f is analytic. With f there is, for each positive integer n, associated a certain spherical series \(\psi_{n,f}\) on a subset of \(S_ n\), the space of Hermitian \(n\times n\) matrices.
Gross, Kenneth I, Richards, Donald St.P
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