Results 11 to 20 of about 5,113,236 (295)
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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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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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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Verification of positive definiteness
BIT Numerical Mathematics, 2006 We present a computational, simple and fast sufficient criterion to verify positive definiteness of a symmetric or Hermitian matrix. The criterion uses only standard floating-point operations in rounding to nearest, it is rigorous, it takes into account ...
Rump, Siegfried M.
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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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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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On Dugundji’s notion of positive definiteness
Proceedings of the American Mathematical Society, 1974 Dugundji’s notion of positive definiteness is generalized to nonnegative real-valued functions on a uniform space. Its relations with completeness and various notions of compactness are investigated.
Chi Song Wong
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Positive definiteness of forms: Numerical identification
SIAM Journal on Control and Optimization, 2020 The question about positive definiteness or semidefiniteness of quadratic forms (or, more generally, polynomial homogeneous forms of an even degree) arises in numerous fields of mathematics and its applications.
Arutyunov A.V., Izmailov A.F.
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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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Positive Definiteness of Symmetric Rank 1 (H-Version) Update for Unconstrained Optimization
مجلة بغداد للعلوم, 2022 Several attempts have been made to modify the quasi-Newton condition in order to obtain rapid convergence with complete properties (symmetric and positive definite) of the inverse of Hessian matrix (second derivative of the objective function).
Saad Shakir Mahmood +2 more
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