Unexpected Behaviors in Higher- Order Positive Feedback Loops

32 D-4455-22Graph of Convergent Periodic Oscillations1A(0)=10-121B(0)=-1213C(0)=03 1 32123-20 1 2 3 4 5 6 7 8 9 10 11 12TimeA: ---------------------------------------------------------------------- 1 1 1units22 2B: -----------------------------------------------------------------------units3 3C: -----------------------------------------------------------------------units3Figure 21: Vensim Equivalent of Figure 8: Convergent periodic oscillations (third-orderpositive feedback loop).Graph of Destabilizing Convergent Periodic Oscillations230A(0)=11B(0)=-12 23 1312312C(0)=0.0001-20 1 2 3 4 5 6 7 8 9 10 11 12TimeA: ------------------------------------------------------------------- 111units222B: ------------------------------------------------------------------- units333C: ------------------------------------------------------------------- unitsFigure 22: Vensim Equivalent 1 of Figure 9: Convergent periodic oscillations destabilizingto exponential growth (third-order positive feedback loop).