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has been cited by the following article:

• TITLE: Nature’s autonomous oscillators

  AUTHORS: Hans G. Mayr, Jeng-Hwa Yee, Marianne Mayr, Robert Schnetzler

  KEYWORDS: Mechanical Clock; Quasi-Biennial Oscillation; Bimonthly Oscillation; Solar Dynamo; Insect Flight; Human Heart

  JOURNAL NAME: Natural Science, Vol.4 No.4, April 24, 2012

  ABSTRACT: Nonlinearity is required to produce autonomous oscillations without external time dependent source, and an example is the pendulum clock. The escapement mechanism of the clock imparts an impulse for each swing direction, which keeps the pendulum oscillating at the resonance frequency. Among nature’s observed autonomous oscillators, examples are the quasi-biennial oscillation of the atmosphere and the 22- year solar oscillation [1]. Numerical models simulate the oscillations, and we discuss the nonlinearities that are involved. In biology, insects have flight muscles, which function autonomously with wing frequencies that far exceed the animals' neural capacity. The human heart also functions autonomously, and physiological arguments support the picture that the heart is a nonlinear oscillator.