Results 11 to 20 of about 505,503 (271)

A New Algorithm for Finding Rational First Integrals of Polynomial Vector Fields [PDF]

open access: yesQualitative Theory of Dynamical Systems, 2010
We present a new method to compute rational first integrals of planar polynomial vector fields. The algorithm is in general much faster than the usual methods and also allows to compute the remarkable curves associated to the rational first integral of the system.
Ferragut Amengual, Antoni Manel   +1 more
openaire   +5 more sources

Polynomial and rational first integrals for planar quasi--homogeneous polynomial differential systems

open access: yesDiscrete & Continuous Dynamical Systems - A, 2013
In this paper we find necessary and sufficient conditions in order that a planar quasi-homogeneous polynomial differential system has a polynomial or a rational first integral. We also prove that any planar quasi-homogeneous polynomial differential system can be transformed into a differential system of the form u˙ = uf(v), ˙v = g(v) with f(v) and g(v)
Giné, Jaume   +2 more
exaly   +8 more sources

Darboux Linearization and Isochronous Centers with a Rational First Integral

open access: yesJournal of Differential Equations, 1997
The authors consider the following planar system \[ \dot x = -y + \sum_{i+j=2}^{n} a_{ij}x^i y^j ,\quad \dot y = x + \sum_{i+j=2}^{n} b_{ij}x^i y^j ,\quad\quad (x,y)\in \mathbb{R}^2 \tag{1} \] where \(a_{ij}\) and \(b_{ij}\) are real numbers. Let the system (1) has a center, and let \(T\) be a period-function, i.e.
Mardešić, P.   +2 more
openaire   +4 more sources

A New Expression for the Coulomb Potential Corresponding to the Product of Two Exponential Functions Based on the Properties of the Integral Representations of the Bessel Functions

open access: yesTrends in Computational and Applied Mathematics, 2023
The calculation of the Coulomb Potential corresponding to the product of two Exponential Type Functions, inherently has numerical challenges that must be resolved.
C. J. Alturria Lanzardo   +4 more
doaj   +1 more source

Controllability and optimal speed-in-action of linear systems with boundary conditions [PDF]

open access: yesҚарағанды университетінің хабаршысы. Математика сериясы, 2023
The paper proposes a method for solving the problem of optimal performance for linear systems of ordinary differential equations in the presence of phase and integral restrictions, when the initial and final states of the system are elements of ...
S. Aisagaliev, G.T. Korpebay
doaj   +3 more sources

Geometry and integrability of quadratic systems with invariant hyperbolas

open access: yesElectronic Journal of Qualitative Theory of Differential Equations, 2021
Let QSH be the family of non-degenerate planar quadratic differential systems possessing an invariant hyperbola. We study this class from the viewpoint of integrability.
Regilene Oliveira   +2 more
doaj   +1 more source

The field of rational constants of the Volterra derivation; pp. 133–135 [PDF]

open access: yesProceedings of the Estonian Academy of Sciences, 2014
We describe the field of rational constants of the four-variable Volterra derivation. Thus, we determine all rational first integrals of its corresponding system of differential equations. Such derivations play a role in population biology, laser physics,
Janusz Zieliński
doaj   +1 more source

New solitary electrostatic structures for Zakharov model in subsonic limit for solar-wind

open access: yesResults in Physics, 2022
A theoretical study of Zakharov model in subsonic limit has been investigated for plasma waves solutions via many solitary and huge structures. The electrostatic field modulations, the first integral and the rational self-focusing nonlinearly methods ...
A. Almutairi   +3 more
doaj   +1 more source

Darboux and Analytic First Integrals of Kingni–Jafari System with Only One Stable Equilibrium Point.

open access: yesZanco Journal of Pure and Applied Sciences, 2020
In this paper, we illustrate by an evidence that the Kingni–Jafari differential system where  and   are real parameters has no Darboux and rational first integrals for any value of   Furthermore, we show that this system has no global first integrals ...
Shno F. Muhammed   +2 more
doaj   +3 more sources

Generalized rational first integrals of analytic differential systems

open access: yesJournal of Differential Equations, 2011
In this paper we mainly study the necessary conditions for the existence of functionally independent generalized rational first integrals of ordinary differential systems via the resonances. The main results extend some of the previous related ones, for instance the classical Poincar 's one \cite{Po}, the Furta's one, part of Chen's ones, and the Shi ...
Cong, Wang, Llibre, Jaume, Zhang, Xiang
openaire   +6 more sources

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