Results 11 to 20 of about 5,889,360 (355)
On positive definite sequences and functions [PDF]
Tohoku Mathematical Journal, 1950 Matsugu Tsuji
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Strict Positive Definiteness of Convolutional and Axially Symmetric Kernels on d-Dimensional Spheres [PDF]
Journal of Fourier Analysis and Applications, 2021 The paper introduces new sufficient conditions of strict positive definiteness for kernels on d-dimensional spheres which are not radially symmetric but possess specific coefficient structures.
Martin Buhmann, Janin Jäger
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Positive definiteness of real quadratic forms resulting from the variable-step approximation of convolution operators [PDF]
Science China Mathematics, 2020 The positive definiteness of real quadratic forms with convolution structures plays an important role in stability analysis for time-stepping schemes for nonlocal operators.In this work, we present a novel analysis tool to handle discrete convolution ...
Hong-lin Liao, T. Tang, Tao Zhou
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AIMS Mathematics, 2021 Positive definite polynomials are important in the field of optimization. H-tensors play an important role in identifying the positive definiteness of an even-order homogeneous multivariate form.
Dongjian Bai, Feng Wang
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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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Some new criteria for judging H-tensors and their applications
AIMS Mathematics, 2023 H-tensors play a key role in identifying the positive definiteness of even-order real symmetric tensors. Some criteria have been given since it is difficult to judge whether a given tensor is an H-tensor, and their range of judgment has been limited.
Wenbin Gong, Yaqiang Wang
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Positive definite hyperfunctions [PDF]
Nagoya Mathematical Journal, 1995 S. Bochner proved the following theorem in [B].
Chung, Jaeyoung +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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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 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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