Results 21 to 30 of about 808,598 (165)
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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The Wave Function of the Universe by the New Euclidean Path-integral Approach in Quantum Cosmology [PDF]
, 1992 The wave function of the universe is evaluated by using the Euclidean path integral approach. As is well known, the real Euclidean path integral diverges because the Einstein-Hilbert action is not positive definite.
Ishikawa, Atushi, Ueda, Haruhiko
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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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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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On directional derivatives of trace functionals of the form $A\mapsto\Tr(Pf(A))$
, 2018 Given a function $f:(0,\infty)\rightarrow\RR$ and a positive semidefinite $n\times n$ matrix $P$, one may define a trace functional on positive definite $n\times n$ matrices as $A\mapsto \Tr(Pf(A))$.
Girard, Mark W.
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Families of completely positive maps associated with monotone metrics [PDF]
, 2013 An operator convex function on (0,\infty) which satisfies the symmetry condition k(1/x) = x k(x) can be used to define a type of non-commutative multiplication by a positive definite matrix (or its inverse) using the primitive concepts of left and right ...
Hiai, Fumio +3 more
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POSITIVE DEFINITE FUNCTIONS AND SHARP INEQUALITIES FOR PERIODIC FUNCTIONS
Ural Mathematical Journal, 2017 Let \(\varphi\) be a positive definite and continuous function on \(\mathbb{R}\), and let \(\mu\) be the corresponding Bochner measure. For fixed \(\varepsilon,\tau\in\mathbb{R}\), \(\varepsilon\ne 0\), we consider a linear operator \(A_{\varepsilon,\tau}
Viktor P. Zastavnyi
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The Sequential Generation of Gaussian Random Fields for Applications in the Geospatial Sciences
ISPRS International Journal of Geo-Information, 2014 This paper presents practical methods for the sequential generation or simulation of a Gaussian two-dimensional random field. The specific realizations typically correspond to geospatial errors or perturbations over a horizontal plane or grid. The errors
John Dolloff, Peter Doucette
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An Improved Sequential Quadratic Programming Method Based on Positive Constraint Sets
Chemical Engineering Transactions, 2020 SQP (sequential quadratic programming) is an effective method to solve nonlinear constraint problems, widely used in chemical process simulation optimization.
Li Xia +5 more
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Strictly Positive Definite Functions
Journal of Approximation Theory, 1996 A complex-valued continuous function defined on \(\mathbb{R}\) is said to be strictly positive definite on \(\mathbb{R}\) if the \(n\) by \(n\) matrix \((f(x_i- x_j))\) is positive definite for all choices of pairwise distinct points \(x_1,x_2,\dots,x_n\in\mathbb{R}\), and all \(n\geq 1\).
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