Research Article

Towards Sophisticated Air Traffic Control System Using Formal Methods

Box 10

INVARIANTS
inv1: deadline ∈ aircrafts_in_airport ⟶ 
inv3: ready_to_takeoff_aircrafts ⊆ aircrafts_in_airport
inv2: the_ready_to_takeoff_moment ∈ ready_to_takeoff_aircrafts ⟶ 
inv4: ∀A·(A ∈ ready_to_takeoff_aircrafts ⇒ A ∈ aircrafts_in_airport ∧ statusof(A)=ReadyT)