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Growth Cycle
A growth cycle is the basic unit of SLEUTH execution. It begins by setting each of the coefficients to a unique value. Each of the growth rules are then applied. Finally, the resulting growth rate is evaluated. If the growth rate exceeds or falls short of the CRITICAL_HIGH or CRITICAL_LOW values, model self-modification is applied. Self-modification will slightly alter the coefficient values to simulate accelerated or depressed growth that is related with boom and bust conditions in urban development.

1) Set coefficient values
( _ _ _ _ _ )

2) Apply Growth Rules

3) Self-Modification
  1. UGM
  2. DLM
  • Calculate growth rate (GR)
  • If (GR > CRITICAL_HIGH)
       modify coefficients for    BOOM state
  • If (GR < CRITICAL_LOW)
       modify coefficients for
       BUST state