Results 1 to 10 of about 185,528 (178)
Acta et Commentationes: Ştiinţe Exacte şi ale Naturii, 2023 In this paper we find conditions for a singular point O(0, 0) of a center or a focus type to be a center, in a cubic differential system with one invariant straight line and one invariant cubic.
Dumitru Cozma
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Acta et Commentationes: Ştiinţe Exacte şi ale NaturiiIn this work we find the center conditions for a cubic system of differential equations with a critical point of a center or a focus type having one invariant straight line and one invariant conic. The center-focus problem is studied by using the Darboux
Dumitru Cozma
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CENTER CONDITIONS FOR A CUBIC DIFFERENTIAL SYSTEM WITH ONE INVARIANT STRAIGHT LINE
Acta et Commentationes: Ştiinţe Exacte şi ale Naturii, 2020 We find conditions for a singular point
Dumitru COZMA, Angela MATEI
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Cubic systems with invariant affine straight lines of total parallel multiplicity seven
Electronic Journal of Differential Equations, 2013 In this article, we study the planar cubic differential systems with invariant affine straight lines of total parallel multiplicity seven. We classify these system according to their geometric properties encoded in the configurations of invariant ...
Alexandru Suba +2 more
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Quadratic systems with invariant straight lines of total multiplicity two having Darboux invariants [PDF]
Communications in Contemporary Mathematics, 2021 In this paper, we present the global phase portraits in the Poincaré disc of the planar quadratic polynomial systems which admit invariant straight lines with total multiplicity two and Darboux invariants.
Jaume Llibre, Regilene D. S. Oliveira
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Electronic Journal of Qualitative Theory of Differential Equations, 2023 In this article we consider the class $\textbf{CSL}_7^{2r2c \infty}$ of non-degenerate real planar cubic vector fields, which possess two real and two complex distinct infinite singularities and invariant straight lines of total multiplicity 7, including
Cristina Bujac +2 more
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Evaluation of the Noise Immunity of the MIAM Communication System
Proceedings of the International Conference on Applied Innovations in IT, 2021 The article proposes a modification of the known invariant amplitude modulation that transmits the values of information elements by the ratio of the lengths of the signal vectors lying on a straight line passing through the origin of the coordinate ...
Ivan Pavlov +4 more
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A REVIEW OF THE ONE-PARAMETER DIVISION UNDISTORTION MODEL [PDF]
ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2021 The one-parameter division undistortion model by (Lenz, 1987) and (Fitzgibbon, 2001) is a simple radial distortion model with beneficial algebraic properties that allows to reason about some problems analytically that can only be handled numerically in ...
B. Erdnüß, B. Erdnüß
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On the number of invariant straight lines for polynomial differential systems [PDF]
Pacific Journal of Mathematics, 1998 Let \(\alpha(n)\) be the maximum number of invariant straight lines possible in a polynomial differential system of degree \(n>1\) having finitely many invariant straight lines. By using a method in graph theory developed by the second author, the remarkable result: \(\alpha(5)= 14\) (together with many upper and lower bounds for \(\alpha(6),\alpha(7),\
Artés, Joan C. +2 more
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Cubic Kolmogorov system with invariant straight lines
Nonlinear Analysis: Theory, Methods & Applications, 2001 47
Saez, E, Szanto, I, Gonzalez-Olivares, E
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