Title of article :
A New Approach for Solving Nonlinear Differential Equations with Poincare Map and Poincare Section
Author/Authors :
Sadeghi Bajestani, Ghasem Department of Biomedical Engineering - Islamic Azad University, Science and Research Branch,Tehran, Iran , Sheikhani, Ali Department of Biomedical Engineering - Islamic Azad University, Science and Research Branch,Tehran, Iran , Hashemi Golpayegani, Mohammad Reza Department of Biomedical Engineering - Amirkabir University, Tehran, Iran , Ashrafzadeh, Farah Paediatrics Neurology division - Ghaem Hospital - Mashhad University of Medical Sciences, Iran , Hebrani, Paria Department of Paediatrics - Mashhad University of Medical Sciences, Iran
Abstract :
Solving many of the scientific problems in physics and engineering leads to differential equations, which in many
cases no analytical answers can be found. The question to be considered is that, if the available numerical methods for
solving deferential equations (that are all done by computers) are reliable.Is the Lipchitz validity assumption on
differential equations with nonlinear dynamics true? What is the reason for the contradictory outcomes of solving a
simple equation using numerical methods? Do the outcomes show the reality of the dynamic system? What is the
acceptable replacement for the current methods?All the phenomena of the world have bifurcations, singularity,
dissociation, behavioral changes and interaction; and today, science with assumptions like neglecting interactions and
singularities, consider the systems as a continues model, although we are in need of a model in which we can solve the
problem without inserting the changes in time approach to zero chain.In this article, accompanied by showing different
and contradictory results –which are all wrong– numerical methods for solving a simple differential equation and
comparing them with analytical method, we introduce Poincare as a substitution for overcoming this scientific
derivation.In this article we solved a differential equation with common numerical methods in MATLAB, and showed
that these methods produce conflicting outcomes, and then we solved it using Poincare. After showing the invalidity
of common numerical methods and introduction of a simple decomposition method, we investigated Van der Pol
equations using Poincare, and showed the fact that Poincare can simply show the system dynamics like a flashlight.
Keywords :
Poincare , Van der Pol oscillator , RungeKutta , Euler , Lipchitz
Journal title :
Astroparticle Physics