Results 21 to 30 of about 9,956,543 (298)
On average theta functions of certain quadratic forms as sums of Eisenstein series
Open Mathematics, 2023 Let QQ be an integral positive definite quadratic form of level NN in 2k2k variables. Further, we assume that (−1)kN{\left(-1)}^{k}N is a fundamental discriminant. We express the average theta function of QQ as an explicit sum of Eisenstein series, which
Eum Ick Sun
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Isolated periodic wave trains in a generalized Burgers–Huxley equation
Electronic Journal of Qualitative Theory of Differential Equations, 2022 We study the isolated periodic wave trains in a class of modified generalized Burgers–Huxley equation. The planar systems with a degenerate equilibrium arising after the traveling transformation are investigated.
Qinlong Wang +3 more
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The theory and applications of complex matrix scalings
Special Matrices, 2014 We generalize the theory of positive diagonal scalings of real positive definite matrices to complex diagonal scalings of complex positive definite matrices.
Pereira Rajesh, Boneng Joanna
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Modified projected Newton scheme for non-convex function with simple constraints [PDF]
Yugoslav Journal of Operations Research, 2021 In this paper, a descent line search scheme is proposed to find a local minimum point of a non-convex optimization problem with simple constraints. The idea ensures that the scheme escapes the saddle points and finally settles for a local minimum point ...
Chakraborty Suvra Kanti +1 more
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Derivatives of isotropic positive definite functions on spheres [PDF]
, 2017 We show that isotropic positive definite functions on the d -dimensional sphere which are 2k times differentiable at zero have 2k+[(d−1)/2] continuous derivatives on (0,π) .
Trübner, Mara, Ziegel, Johanna F.
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On positive positive-definite functions and Bochner’s Theorem
Journal of Complexity, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Aicke Hinrichs, Jan Vybíral
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Journal of Algorithms & Computational Technology, 2019 In the field of pattern recognition, using the symmetric positive-definite matrices to represent image set has been widely studied, and sparse representation-based classification algorithm on the symmetric positive-definite matrix manifold has attracted ...
Chu Li, Xiao-Jun Wu
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Fractal and Fractional, 2023 In this article, we provide a metaheuristic-based solution for stability analysis of nonlinear systems. We identify the optimal level set in the state space of these systems by combining two optimization phases.
Faiçal Hamidi +5 more
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Symmetric and Positive Definite Broyden Update for Unconstrained Optimization
مجلة بغداد للعلوم, 2019 Broyden update is one of the one-rank updates which solves the unconstrained optimization problem but this update does not guarantee the positive definite and the symmetric property of Hessian matrix.
Saad et al.
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On Positive Definiteness of Some Functions
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 \(k= 1,2,\dots, n\).
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