Results 251 to 260 of about 471,373 (286)

On the Planar Piecewise Quadratic 1-Center Problem

Algorithmica, 2008
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Puerto, J., Rodríguez-Chía, A. M., Tamir, A.   +2 more
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The Number of Limit Cycles Bifurcating from a Quadratic Reversible Center

International Journal of Bifurcation and Chaos, 2021
By using the first order Melnikov function method with multiple parameters presented in [Han & Xiong, 2014], we prove that [Formula: see text] limit cycles can bifurcate from the quadratic reversible center [Formula: see text] under [Formula: see text]th degree polynomial perturbations for [Formula: see text]. Our result in this paper improves the
Feng Liang, Yeqing Liu, Chong Chen
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An analytic center quadratic cut method for the convex quadratic feasibility problem

Mathematical Programming, 2002
The first problem studied in the article is to find a point in a convex set, which is contained in the unit ball and contains a full-dimensional ball of sufficiently small radius. The convex set is described by the intersection of a finite, yet large number of convex quadratic inequalities.
Sharifi Mokhtarian, Faranak, Goffin, Jean-Louis   +1 more
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Quadratic perturbations of a class of quadratic reversible center of genus one

Science China Mathematics, 2012
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Liang, Haihua, Wu, Kuilin, Zhao, Yulin
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Quadratic perturbations of a quadratic reversible center of genus one

Frontiers of Mathematics in China, 2011
The bifurcation of limit cycles for small quadratic perturbations of the planar system with a center \[ x'=y-28x^2+32y^2,\quad y'=-x(1+32y) \] is studied. This is case (r15) in the classification of all quadratic systems whose generic complexified periodic orbits define elliptic curves [\textit{S. Gautier, L. Gavrilov} and \textit{I. D.
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Averaging analysis of a perturbated quadratic center

Nonlinear Analysis: Theory, Methods & Applications, 2001
The authors consider planar polynomial dynamical systems. Using the averaging theory for studying limit cycle bifurcations, they prove that if the quadratic system with a center at the origin \(dx/dt=-y(1+x),\) \(dy/dt=x(1+x)\) will be perturbed by polynomials of degree \(n\) to the polynomial systems \(dx/dt=-y(1+x)+\varepsilon p(x,y),\) \(dy/dt=x(1+x)
Llibre, Jaume, Pérez del Río, Jesús S., Rodríguez, José Angel   +2 more
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Centers and Isochronous Centers of Newton Systems with Force Function Quadratic in Velocities

Differential Equations, 2019
Necessary and sufficient conditions are obtained for a center as well as an isochronous center of holomorphic Newton equations with force function quadratic in velocities.
Amel'kin, V. V., Rudenok, A. E.
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Geometric interpretation of quadratic centers

2021
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Cooling Control of Data Centers Using Linear Quadratic Regulators

2018 26th Mediterranean Conference on Control and Automation (MED), 2018
One of the largest contributions to a data center's power usage is its cooling system. One way to decrease the energy usage of a cooling systems by introducing an automatic control adapting the capacity of cooling units is addressed by this paper. Firstly, different configurations of linear quadratic regulators are designed and then evaluated using the
Winston Garcia-Gabin, Kateryna Mishchenko, Erik Berglund   +2 more
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The Scalar Center for Quadratic Jordan Algebras

Communications in Algebra, 2004
Abstract We propose that an element of a Jordan algebra J should be considered “central” if it is a scalar multiple of 1 in some tight unital extension of J. For Jordan algebras with no trivial ideals, this yields an acceptable center. Here it is important that an algebra with no extreme elements has a unique tight unital hull.
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