Results 11 to 20 of about 27,914 (184)
Acta et Commentationes: Ştiinţe Exacte şi ale Naturii, 2023 The quartic differential systems with a non-degenerate monodromic critical point and non-degenerate infinity are considerated. We show that in this family the maximal multiplicity of the line at infinity is seven.
Alexandru Șubă, Olga Vacaraș
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Acta et Commentationes: Ştiinţe Exacte şi ale NaturiiIn this paper the quartic differential systems with a center-focus critical point and non-degenerate infinity are examined. We show that in this family the maximal multiplicity of an affine invariant straight line is six. Modulo the affine transformation
Olga Vacaraș
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Isochronicity of bi-centers for symmetric quartic differential systems
Discrete and Continuous Dynamical Systems - B, 2022 <p style='text-indent:20px;'>In this paper we investigate the simultaneous existence of isochronous centers for a family of quartic polynomial differential systems under four different types of symmetry. Firstly, we find the normal forms for the system under each type of symmetry.
Fernandes, Wilker +2 more
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Center cyclicity of a family of quartic polynomial differential system [PDF]
Nonlinear Differential Equations and Applications NoDEA, 2016 The first and third authors are partially supported by a MINECO grant number MTM2014-53703-P and by a CIRIT grant number 2014 SGR 1204. The second author is partially supported by a MINECO grant MTM2013-40998-P, an AGAUR grant number 2014SGR 568, two FP7-PEOPLE-2012-IRSES numbers 316338 and 318999.
Isaac A. García +2 more
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The Euler-Jacobi formula and the planar quadratic-quartic polynomial differential systems
Proceedings of the American Mathematical Society, 2020 The Euler-Jacobi formula provides an algebraic relation between the singular points of a polynomial vector field and their topological indices. Using this formula we obtain the configuration of the singular points together with their topological indices for the planar quadratic-quartic polynomial differential systems when these systems have eight ...
Llibre, Jaume, Valls, Clàudia
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The explicit secular equation for surface acoustic waves in monoclinic elastic crystals [PDF]
, 2012 The secular equation for surface acoustic waves propagating on a monoclinic elastic half-space is derived in a direct manner, using the method of first integrals.
Destrade, Michel
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Electronic Journal of Differential Equations, 2015 We study the number of limit cycles that bifurcate from the periodic solutions surrounding a uniform isochronous center located at the origin of the quartic polynomial differential system =-y xy(x^2 y^2), =x y^2(x^2 y^2), when it is perturbed inside the class of all quartic polynomial differential systems.
Itikawa, Jackson, Llibre, Jaume
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Advances in Difference Equations, 2018 In this paper, we propose an extrapolation full multigrid (EXFMG) algorithm to solve the large linear system arising from a fourth-order compact difference discretization of two-dimensional (2D) convection diffusion equations.
Ming Li, Zhoushun Zheng, Kejia Pan
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Hyperbolic Structures and Root Systems [PDF]
, 2010 We discuss the construction of a one parameter family of complex hyperbolic structures on the complement of a toric mirror arrangement associated with a simply laced root system.
Dijk, G. van +2 more
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Differential equations for septic theta functions
, 2013 We demonstrate that quotients of septic theta functions appearing in S. Ramanujan's Notebooks and in F. Klein's work satisfy a new coupled system of nonlinear differential equations with interesting symmetric form.
Huber, Tim, Lara, Danny
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