Science in China Series A: Mathematics

, Volume 42, Issue 10, pp 1047–1058 | Cite as

Invariant tori in nonlinear oscillations

  • Bin Liu
  • Yiqian Wang


The boundedness of all the solutions for semilinear Duffing equationx″ + ω2 x + φ(x) =p(t), ω ∈ ℝ+ℕ is proved, wherep (t) is a smooth 2π-periodic function and the perturbation ⌽(x) is bounded.


invariant tori semilinear Duffing equations boundedness of solutions 


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Copyright information

© Science in China Press 1999

Authors and Affiliations

  • Bin Liu
    • 1
  • Yiqian Wang
    • 1
  1. 1.School of Mathematical SciencesPeking UniversityBeijingChina

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