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4. Epidemics in the Marine System
EPIDEMIC WITH SUBMODEL
NET_BIRTH_RATE = .02
NOT INFECTED = IMMUNE + SUSCEPTIBLE
DISEASE = INFECTED + SUSCEPTIBLE + IMMUNE
INFLOWS:
NET_BIRTHS = NET_BIRTH_RATE*NOT_INFECTED*(lDISEASE/4000)
OUTFLOWS :
DEATHS = DEATHS'
IMMUNE(t) = IMMUNE (t-dt) + (RECOVERY-LOSS_OF_IMMUNITY)
* dt
INIT IMMUNE = 0
TRANSIT TIME = 20
INFLOW LIMIT = =
CAPACITY = 00
INFLOWS:
RECOVERY = CONVEYOR OUTFLOW
OUTFLOWS:
LOSS_OF_IMMUNITY = CONVEYOR OUTFLOW
INFECTED(t) = INFECTED (t-dt) + (INFECTION-RECOVERYDEATHS') * dt
INIT INFECTED = 10
TRANSIT TIME = 3
INFLOW LIMIT = =
CAPACITY = =
INFLOWS:
INFECTION = CONTACT_RATE*SUSCEPTIBLE*INFECTED
OUTFLOWS :
RECOVERY = CONVEYOR OUTFLOW
DEATHS' = LEAKAGE OUTFLOW
LEAKAGE FRACTION = MORTALITY_RATE
NO-LEAK ZONE = 2
SUSCEPTIBLE(t) = SUSCEPTIBLE(t-dt) + (NET_BIRTHS' +
LOSS_OF_IMMUNITY-INFECTION) * dt
INIT SUSCEPTIBLE = 1990
INFLOWS :
NET_BIRTHS' = NET_BIRTHS