Results 21 to 30 of about 23,170 (262)
Hilbert′s 16th Problem for Quadratic Vector Fields
Journal of Differential Equations, 1994 The second part of Hilbert's 16th problem is to determine the number and relative position of the limit cycles of a polynomial vector field in the plane. This problem remains open even for the case of a vector field whose components are quadratic polynomials.
Dumortier, F. +2 more
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Semicompleteness of homogeneous quadratic vector fields [PDF]
Annales de l'Institut Fourier, 2006 We investigate the quadratic homogeneous holomorphic vector fields on C n that are semicomplete, this is, those whose solutions are single-valued in their maximal definition ...
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Exact parametric representations of orbits defined by cubic Hamiltonian
上海师范大学学报. 自然科学版, 2014 In this paper,we show that for any given planar cubic algebraic curves defined by a quadratic Hamiltonian vector field,we can always have their exact explicit parametric representations.We use a model of micro-structured solid to show an application of ...
Jibin Li
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On the dualization of Born–Infeld theories
Physics Letters B, 2015 We construct a general Lagrangian, quadratic in the field strengths of n abelian gauge fields, which interpolates between BI actions of n abelian vectors and actions, quadratic in the vector field-strengths, describing Maxwell fields coupled to non ...
Laura Andrianopoli +2 more
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Oxygen nonstoichiometry and magnetic properties of doped manganites La0.7Sr0.3Mn0.95Fe0.05O3-δ [PDF]
Modern Electronic Materials, 2021 In this work, solid solutions of La0.7Sr0.3Mn0.95Fe0.05O3-δ with different oxygen content were obtained by the solid-phase reactions technique. Based on the investigation of the dynamics of changes in the oxygen index (3 – δ) during heating of the ...
Nikolay A. Kalanda +6 more
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Spacetimes with vector distortion: Inflation from generalised Weyl geometry
Physics Letters B, 2016 Spacetime with general linear vector distortion is introduced. Thus, the torsion and the nonmetricity of the affine connection are assumed to be proportional to a vector field (and not its derivatives).
Jose Beltrán Jiménez, Tomi S. Koivisto
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Palatini formulation of the conformally invariant $$f\left( R,L_m\right) $$ f R , L m gravity theory
European Physical Journal C: Particles and Fields, 2022 We investigate the field equations of the conformally invariant models of gravity with curvature-matter coupling, constructed in Weyl geometry, using the Palatini formalism.
Tiberiu Harko, Shahab Shahidi
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Journal of Electrical and Computer Engineering, 2021 This paper proposes an optimal gain-scheduling for linear quadratic regulator (LQR) control framework to improve the performance of wind turbines based Doubly Fed Induction Generator (DFIG).
Ashraf Radaideh +2 more
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AppliedMathAfter linear differential systems in the plane, the easiest systems are quadratic polynomial differential systems in the plane. Due to their nonlinearity and their many applications, these systems have been studied by many authors.
Joan Carles Artés +2 more
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Heterotic Kerr-Schild Double Field Theory and its double Yang-Mills formulation
Journal of High Energy Physics, 2022 We present a formulation of heterotic Double Field Theory (DFT), where the fundamental fields are in O(D, D) representations. The theory is obtained splitting an O(D, D + K ) duality invariant DFT.
Eric Lescano, Sourav Roychowdhury
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