Results 61 to 70 of about 185,528 (178)
The intrinsic complexity of parametric elimination methods [PDF]
, 1997 This paper is devoted to the complexity analysis of a particular property, called "algebraic robustness" owned by all known symbolic methods of parametric polynomial equation solving (geometric elimination).
Heintz, J. +3 more
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Electronic Journal of Differential Equations, 2018 In this article we consider a class of quadratic polynomial differential systems in the plane having a hyperbola and a straight line as invariant algebraic curves, and we classify all its phase portraits.
Jaume Llibre, Jiang Yu
doaj
Gauge-invariant dressed fermion propagator in massless QED_3
, 2005 The infrared behaviour of the gauge-invariant dressed fermion propagator in massless QED_3 is discussed for three choices of dressing. It is found that only the propagator with the isotropic (in three Euclidean dimensions) choice of dressing is ...
Appelquist +24 more
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Electronic Journal of Differential Equations, 2015 In this article we study a class of integrable quadratic systems and classify all its phase portraits. More precisely, we characterize the class of all quadratic polynomial differential systems in the plane having an ellipse and a straight line as ...
Jaume Llibre, Jiang Yu
doaj
Integrability conditions for a cubic system with two invariant straight lines
, 2021 We consider the cubic system of di erential equations having a singular point M with pure imaginary eigenvalues and two parallel invariant straight lines l1; l2. Then by using a nondegenerate transformation of variables and a time rescaling the system can be brought to the form.
Cozma, D.V., Cozma, D.
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A homological definition of the HOMFLY polynomial
, 2006 We give a new definition of the knot invariant associated to the Lie algebra su_{N+1}. The knot or link must be presented as the plat closure of a braid. The invariant is then a homological intersection pairing between two submanifolds of a configuration
Bigelow +6 more
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Cozma’s centers with invariant straight lines and conics
, 2014 We consider the center-focus problem for cubic systems with two invariant straight lines and one invariant conic. In [1] it is proved that a weak focus is a center for such systems if and only if the first four Liapunov quantities vanish. Seven classes of cubic systems with the center at the origin with two invariant straight lines and one invariant ...
Sadovschii, A., Shcheglova, T.V.
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On the centers of cubic polynomial differential systems with four invariant straight lines [PDF]
Topological Methods in Nonlinear Analysis, 2020 Assume that a cubic polynomial differential system in the plane has four invariant straight lines in generic position, i.e. they are not parallel and no more than two straight lines intersect in a point. Then such a differential system only can have 0, 1 or 3 centers.
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Dynamics of abelian subgroups of GL(n, C): a structure's Theorem
, 2005 In this paper, we characterize the dynamic of every abelian subgroups $\mathcal{G}$ of GL($n$, $\mathbb{K}$), $\mathbb{K} = \mathbb{R}$ or $\mathbb{C}$. We show that there exists a $\mathcal{G}$-invariant, dense open set $U$ in $\mathbb{K}^{n}$ saturated
Adlene Ayadi +4 more
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The vortex filament dynamics: New viewpoint on the problems of energy and effective mass
Vestnik Samarskogo Gosudarstvennogo Tehničeskogo Universiteta. Seriâ: Fiziko-Matematičeskie Nauki, 2019 The paper is devoted to the dynamics of a zero thickness infinite vortex filament in the local induction approximation. The filament is asymptotically considered as a straight line defined by the certain vector ${\boldsymbol{b}}_3 \in E_3$. We also
Sergei Vladimirovich Talalov
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