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Strict positive definiteness in geostatistics [PDF]
, 2017 Geostatistical modeling is often based on the use of covariance functions, i.e., positive definite functions. However, when interpolation problems have to be solved, it is advisable to consider the subset of strictly positive definite functions. Indeed,
POSA, Donato +3 more
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Strict positive definiteness on spheres via disk polynomials
International Journal of Mathematics and Mathematical Sciences, 2002 We characterize complex strictly positive definite functions on spheres in two cases, the unit sphere of ℂq, q≥3, and the unit sphere of the complex ℓ2. The results depend upon the Fourier-like expansion of the functions in terms of disk polynomials and,
V. A. Menegatto, A. P. Peron
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Positive definite indistinguishability operators [PDF]
Fuzzy Sets and Systems, 2020 Peer ...
Recasens Ferrés, Jorge +1 more
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Positive definiteness of Hermitian interval matrices [PDF]
, 2009 We present a new necessary and sufficient criterion to check the positive definiteness of Hermitian interval matrices. It is shown that an n×n Hermitian interval matrix is positive definite if and only if its 4n-1(n-1)!
Hou, Xiaorong +3 more
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Mathematics, 2023 This paper is devoted to the spectral analysis of one class of integral operators, associated with the boundary-value problems for differential equations of fractional order.
Tatiana Matseevich, Temirkhan Aleroev
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Positive Definiteness of Discrete Quadratic Functionals [PDF]
, 1997 This summary of the author\u27s talk presented in Oberwolfach motivates the importance of certain discrete quadratic functionals and characterizes so-called positive definiteness of them via a condition on the principal solution of a related linear ...
Bohner, Martin, Martin Bohner
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Using stability analysis of discrete elastic systems to study the buckling of nanostructures
Archives of Mechanics, 2012 Stubility/instability criteria of discrete elastic systems are used to study the buckling of nanostructures. The deformation of nanostructures is simulated by solving the nonlinear equations of molecular mechanics.
S.N. Korobeynikov +3 more
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Многоязычие в образовательном пространстве, 2021 The purpose of this study is to conduct a comparative typological analysis of the means of expressing the category “Definiteness / Indefiniteness” in German, Tatar and Russian languages and, building on this analysis, to develop a system of exercises ...
A. A. Sibgatullina
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Stable positive definite functions [PDF]
Transactions of the American Mathematical Society, 1975 This paper investigates the stability of positive definite functions on locally compact groups under one parameter groups of automorphisms. As an application of this it is shown that the only probability distributions on
Parthasarathy, K. R., Schmidt, K.
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Intelligent optimization based density matrix reconstruction method with semi-positive constraint
Results in Physics, 2023 Quantum state tomography (QST) is a technique used to reconstruct the density matrix of unknown quantum states based on experimentally obtained measurements. QST is a fundamental tool in the field of quantum information and quantum technology.
Xiaomin Meng +3 more
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