Results 1 to 10 of about 12,336 (117)
New Nonlinear Active Element Dedicated to Modeling Chaotic Dynamics with Complex Polynomial Vector Fields [PDF]
Entropy, 2019 This paper describes evolution of new active element that is able to significantly simplify the design process of lumped chaotic oscillator, especially if the concept of analog computer or state space description is adopted.
Jiri Petrzela, Roman Sotner
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Is the Finite-Time Lyapunov Exponent Field a Koopman Eigenfunction?
Mathematics, 2021 This work serves as a bridge between two approaches to analysis of dynamical systems: the local, geometric analysis, and the global operator theoretic Koopman analysis. We explicitly construct vector fields where the instantaneous Lyapunov exponent field
Erik M. Bollt, Shane D. Ross
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Polynomial reconstruction of staggered unstructured vector fields [PDF]
Theoretical and Applied Mechanics, 2009 Polynomial reconstruction of staggered unstructured vector fields has been considered. Coefficients of such polynomials are determined by the least squares method. Reduction in the rank of the least squares systems caused by the over-specification of the
Vidović Dragan
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Dual active-set algorithm for optimal 3-monotone regression [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2022 The paper considers a shape-constrained optimization problem of constructing monotone regression which has gained much attention over the recent years. This paper presents the results of constructing the nonlinear regression with $3$-monotone constraints.
Gudkov, Alexandr A. +2 more
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Demonstratio Mathematica, 2023 The classification of the phase portraits is one of the classical and difficult problems in the qualitative theory of polynomial differential systems in R2{{\mathbb{R}}}^{2}, particularly for quadratic systems.
Benterki Rebiha, Belfar Ahlam
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Centralizers of elements in Lie algebras of vector fields with polynomial coefficients
Pracì Mìžnarodnogo Geometričnogo Centru, 2022 \abstract{ukrainian}{ Нехай $\mathbb K$ -- алгебраїчно замкнене поле харатеристики нуль, $A = \mathbb K[x_1,\dots,x_n]$ -- кільце многочленів і $R = \mathbb K(x_1,\dots,x_n)$ -- поле раціональних функцій від $n$ змінних.
Анатолій Петрович Петравчук
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Covariants, Invariant Subsets, and First Integrals [PDF]
Épijournal de Géométrie Algébrique, 2020 Let $k$ be an algebraically closed field of characteristic 0, and let $V$ be a finite-dimensional vector space. Let $End(V)$ be the semigroup of all polynomial endomorphisms of $V$.
Frank Grosshans, Hanspeter Kraft
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Finitely curved orbits of complex polynomial vector fields
Anais da Academia Brasileira de Ciências, 2007 This note is about the geometry of holomorphic foliations. Let X be a polynomial vector field with isolated singularities on C². We announce some results regarding two problems: 1.
Albetã C. Mafra
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Periodic perturbations of quadratic planar polynomial vector fields
Anais da Academia Brasileira de Ciências, 2002 In this work are studied periodic perturbations, depending on two parameters, of quadratic planar polynomial vector fields having an infinite heteroclinic cycle, which is an unbounded solution joining two saddle points at infinity.
MARCELO MESSIAS
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The global dynamics of a class of nonlinear vector fields in $\mathbb{R}^3$
Electronic Journal of Qualitative Theory of Differential Equations, 2014 In this paper, we study the geometric properties of a class of nonlinear polynomial vector fields in $\mathbb{R}^3$. By virtue of their induced vector fields, their global topological structures are discussed and we get that there are at least 82 types
Jinhui Zhang +2 more
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