{ "id": "2101.01927", "version": "v1", "published": "2021-01-06T08:52:47.000Z", "updated": "2021-01-06T08:52:47.000Z", "title": "Generalized Liénard systems, singularly perturbed systems, Flow Curvature Method", "authors": [ "Jean-Marc Ginoux", "Dirk Lebiedz", "Jaume Llibre" ], "comment": "19 pages, 1 figure. arXiv admin note: text overlap with arXiv:1408.4894", "categories": [ "math.DS", "math-ph", "math.MP" ], "abstract": "In his famous book entitled \\textit{Theory of Oscillations}, Nicolas Minorsky wrote: \"\\textit{each time the system absorbs energy the curvature of its trajectory decreases} and \\textit{vice versa}\". According to the \\textit{Flow Curvature Method}, the location of the points where the \\textit{curvature of trajectory curve}, integral of such planar \\textit{singularly dynamical systems}, vanishes directly provides a first order approximation in $\\varepsilon$ of its \\textit{slow invariant manifold} equation. By using this method, we prove that, in the $\\varepsilon$-vicinity of the \\textit{slow invariant manifold} of generalized Li\\'{e}nard systems, the \\textit{curvature of trajectory curve} increases while the \\textit{energy} of such systems decreases. Hence, we prove Minorsky's statement for the generalized Li\\'{e}nard systems. Then, we establish a relationship between \\textit{curvature} and \\textit{energy} for such systems. These results are then exemplified with the classical Van der Pol and generalized Li\\'{e}nard \\textit{singularly perturbed systems}.", "revisions": [ { "version": "v1", "updated": "2021-01-06T08:52:47.000Z" } ], "analyses": { "keywords": [ "flow curvature method", "generalized liénard systems", "singularly perturbed systems", "invariant manifold", "trajectory curve" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }