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Van Der Pol dynamics

  1. Dec 5, 2011 #1
    Hi All,

    for a Van Der Pol dyanmical sysetm , governed by the eqautions

    x' = a * (x - 0.3 x ^3 ) - y
    y' = x

    i read at http://www.scholarpedia.org/article/Van_der_Pol_oscillator that when the system is away from the curve y=x−x3/3 , "a relation |x˙| >> |y˙|=O(1/ϵ) is obtained from equations (2) and (3). Therefore, the system moves quickly in the horizontal direction. When the system enters the region where |x−x3/3−y|=O(1/ϵ2) , x˙ and y˙ are comparable because both of them are O(1/ϵ)".

    I really do not get this entirely.`I am unsure of how the relationship involving the infinitesimals are derived. How are these realtionship justified?

    Can anybody please try to give us a hint? Thank you so much

  2. jcsd
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