Results 11 to 20 of about 4,257 (300)
Strict Positive Definiteness of a Product of Covariance Functions
Communications in Statistics - Theory and Methods, 2011 Positive definiteness represents an admissibility condition for a function to be a covariance. Nevertheless, the more restricted condition of strict positive definiteness has received attention in literature, especially in spatial statistics, since it ...
Sandra De Iaco, Donald E Myers, D Posa
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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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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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Positive Definiteness of a Class of Cyclic Symmetric Tensors
Journal of Optimization Theory and ApplicationsFor a 4th order 3-dimensional cyclic symmetric tensor, a sufficient and necessary condition is bulit for its positive semi-definiteness. A sufficient and necessary condition of positive definiteness is showed for a 4th order $n$-dimensional symmetric ...
Yisheng Song
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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 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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Positive definiteness: from scalar to operator-valued kernels [PDF]
Surveys in Mathematics and its Applications, 2021 In this paper we present a short overview of results that provide relationships among scalar, matrix-valued and certain operator-valued positive definite kernels.
V. A. Menegatto
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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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Positive Inductive-Recursive Definitions [PDF]
Logical Methods in Computer Science, 2013 A new theory of data types which allows for the definition of types as initial algebras of certain functors Fam(C) -> Fam(C) is presented. This theory, which we call positive inductive-recursive definitions, is a generalisation of Dybjer and Setzer's theory of inductive-recursive definitions within which C had to be discrete -- our work can ...
Ghani, Neil +2 more
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On a Class of Positive Definite Operators and Their Application in Fractional Calculus
Axioms, 2022 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. Approximation matrices are also investigated.
Temirkhan Aleroev
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