Results 1 to 10 of about 18,620,200 (254)
Electronic Journal of Qualitative Theory of Differential Equations, 2021 In 1998, Artés, Kooij and Llibre proved that there exist 44 structurally stable topologically distinct phase portraits modulo limit cycles, and in 2018 Artés, Llibre and Rezende showed the existence of at least 204 (at most 211) structurally unstable ...
Joan Artés, Marcos Mota, Alex Rezende
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Electronic Journal of Qualitative Theory of Differential Equations, 2021 During the last forty years the theory of integrability of Darboux, in terms of algebraic invariant curves of polynomial systems has been very much extended and it is now an active area of research.
Regilene Oliveira +3 more
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Fundamental response in the vibration control of buildings subject to seismic excitation with ATMD
Selecciones Matemáticas, 2023 The linear quadratic regulator for vibration systems subject to seismic excitations is discussed in his own physical newtonian space as a second-order linear differential system with matrix coefficients.
Fidel Jara Huanca +2 more
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STABILITY OF NONLINEAR DYNAMICAL SYSTEM MOTION UNDER CONSTANTLY ACTING PERTURBATIONS [PDF]
Научно-технический вестник информационных технологий, механики и оптики, 2019 We consider the motion of a mechanical system with several degrees of freedom near zero of the phase space of states under conditions of constantly acting small perturbations. The generalized forces are represented in the dynamic equations by homogeneous
V. G. Melnikov +3 more
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On limit cycles of piecewise differential systems formed by arbitrary linear systems and a class of quadratic systems [PDF]
Mathematica Bohemica, 2023 We study the continuous and discontinuous planar piecewise differential systems separated by a straight line and formed by an arbitrary linear system and a class of quadratic center.
Aziza Berbache
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Parameterization of kernels of the Volterra series for systems given by nonlinear differential equations [PDF]
E3S Web of Conferences, 2023 The presented article is devoted on an issue regarding to the transformation of nonlinear models of a certain class to the Volterra functional series. The new identification method based on analytical input and output of a system was developed.
Kislovskiy Evgeniy +2 more
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Results in Control and Optimization, 2023 A new method for finding a suboptimal control law for a multi fractional spring–mass system as a fractional high order linear quadratic regulator system in the presence of known disturbance is introduced.
Iman Malmir
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The Sine-Cosine Wavelet and Its Application in the Optimal Control of Nonlinear Systems with Constraint [PDF]
Journal of Electrical and Computer Engineering Innovations, 2013 In this paper, an optimal control of quadratic performance index with nonlinear constrained is presented. The sine-cosine wavelet operational matrix of integration and product matrix are introduced and applied to reduce nonlinear differential equations ...
R. Hajmohammadi +2 more
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Науковий вісник Ужгородського університету. Серія: Математика і інформатика, 2018 Constructive conditions for the existence of a nonlinear Noether integral-differential boundary value problem are found. An iterative scheme with quadratic convergence is constructed to find the solution of a nonlinear integral-differential boundary ...
С. М. Чуйко +2 more
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The existence of n-order algebraic curve solutions of planar quadratic polynomial systems
上海师范大学学报. 自然科学版, 2017 In this short article, we show that for any given positive integer n ≥ 2, there is a planar quadratic differential system having n-degree and 2n-degree classical algebraic curve solutions.
Li Jibin
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