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Journal of Inequalities and Applications, 2019 Inspired by symmetric Cauchy tensors, we define fourth-order partially symmetric Cauchy tensors with their generating vectors. In this article, we focus on the necessary and sufficient conditions for the M-positive semi-definiteness and M-positive ...
Haitao Che, Haibin Chen, Yiju Wang
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Positive definiteness and positive differences
Journal of Combinatorial Theory, Series A, 1972 A 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 ...
Sherman, S
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An ℋ-tensor-based criteria for testing the positive definiteness of multivariate homogeneous forms
Open Mathematics, 2022 A positive definite homogeneous multivariate form plays an important role in the field of optimization, and positive definiteness of the form can be identified by a special structured tensor.
Bai Dongjian, Wang Feng
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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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Mathematics, 2022 Positive definite homogeneous multivariate forms play an important role in polynomial problems and medical imaging, and the definiteness of forms can be tested using structured tensors.
Dongjian Bai, Feng Wang
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On Positive Definiteness of Some Functions
Journal of Multivariate Analysis, 2000 Let ρ be a nonnegative homogeneous function on Rn. General structure of the set of numerical pairs (δ, λ), for which the function (1−ρλ(x))δ+ is positive definite on Rn is investigated; a criterion for positive definiteness of this function is given in ...
Zastavnyi, Victor P
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q-positive definiteness and related operators
Journal of Mathematical Analysis and Applications, 2007 We are in progress of extending the family of ‘q-deformed operators’ considered in the previous papers by joining to them q-subnormal as well as q-formally subnormal ones.
Franciszek Hugon Szafraniec
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On the Positive Definiteness of a Functional [PDF]
Canadian Mathematical Bulletin, 1979 In 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.
J. N. Pandey
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New Sufficient Condition for the Positive Definiteness of Fourth Order Tensors
Mathematics, 2018 In this paper, we give a new Z-eigenvalue localization set for Z-eigenvalues of structured fourth order tensors. As applications, a sharper upper bound for the Z-spectral radius of weakly symmetric nonnegative fourth order tensors is obtained and a new Z-
Jun He +3 more
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Conic positive definiteness and sharp minima of fractional orders in vector optimization problems
Journal of Mathematical Analysis and Applications, 2012 Motivated by the fact that the usual positive definiteness does not work in an infinite space, we introduce the concept of S-positive definiteness with respect to an ordering cone in a general Banach space and show that the S-positive definiteness plays ...
Xi Yin Zheng, X Q Yang
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