Results 11 to 20 of about 4,272 (299)
Positive definiteness and positive differences [PDF]
Journal of Combinatorial Theory, Series A, 1972 AbstractA previous inequality [2] in certain context, which holds in the application to the monotonicity of correlations in classical discrete Heisenberg ferromagnets with 2-dimensional spin [3], is extended to positive definiteness of a function on a group.
Sherman, S
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On the Positive Definiteness of a Functional [PDF]
Canadian Mathematical Bulletin, 1979 AbstractIn this note, we have shown that the set of conditions given by Gel'fand and Vilenkin for the positive definiteness of a functional L(ϕ) [1, Theorem 7, p. 285] though sufficient is not necessary, thereby providing an answer to an open problem posed by them [1, Theorem 7, p. 285].
J. N. Pandey
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On Positive Definiteness of Some Functions [PDF]
Journal of Multivariate Analysis, 2000 Let \(E\) be a linear space over \(\mathbb{R}\) and let \(\rho(x)\) be the \(\ell^n_p\)-norm in \(\mathbb{R}^n\). A function \(f: E\to\mathbb{C}\) is called definite if \(\sum^n_{k,j=1} c_k\overline c_jf(x_k- x_j)\geq 0\) for all \(n\in\mathbb{N}\), \(x_k\in E\), \(c_k\in\mathbb{C}\) for \(k= 1,2,\dots, n\).
Zastavnyi, Victor P
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On Elastic Stability and Positive Definiteness for One-Dimensional Quasicrystals [PDF]
CrystalsIn this work, a proper formulation of the elastic stability and positive definiteness of the elastic energy density of one-dimensional quasicrystals is provided. Based on an appropriate Voigt notation, the Sylvester criterion is applied and the necessary
Eleni Agiasofitou, Markus Lazar
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Transporting positive definiteness [PDF]
, 2022 This is a rough guide to the topic which might be worthy to develop further on. Expanding positive definiteness beyond its presupposed scope is intriguing due to a number of possible applications. The paper though looking at the first glance a little bit
Szafraniec, Franciszek
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Positive definiteness in coupled strain gradient elasticity [PDF]
, 2021 The linear theory of coupled gradient elasticity has been considered for hemitropic second gradient materials, specifically the positive definiteness of the strain and strain gradient energy density, which is assumed to be a quadratic form of the strain ...
Altenbach, Holm +2 more
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Retaining positive definiteness in thresholded matrices [PDF]
, 2012 Positive definite (p.d.) matrices arise naturally in many areas within mathematics and also feature extensively in scientific applications. In modern high-dimensional applications, a common approach to finding sparse positive definite matrices is to ...
Guillot, Dominique, Rajaratnam, Bala
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V-singular values of rectangular tensors and their applications
Journal of Inequalities and Applications, 2019 The positive definiteness of rectangular tensors has wide applications in solid mechanics and quantum physics. By modifying the existing definition of singular value for rectangular tensors, some V-singular value inclusion sets for rectangular tensors ...
Jun He +3 more
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Nonsingularity, positive definiteness, and positive invertibility under fixed-point data rounding [PDF]
, 2007 summary:For a real square matrix $A$ and an integer $d\ge 0$, let $A_{(d)}$ denote the matrix formed from $A$ by rounding off all its coefficients to $d$ decimal places.
Rohn, Jiří
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Predicative definite NPIs in Norwegian
Nordlyd: Tromsø University Working Papers on Language & Linguistics, 2011 In Norwegian, a weak quantifier or a scalar adjective with a positive value may combine with a definite noun and thereby form an attenuating NPI. These phrases, which I call predicative definite NPIs, are exceptional as nominal phrases, since they do not
Marit Julien
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