(Inherited-Facet-Value Slot-Value-Type Elevator Elevator.Mbeam Machine_Beam_Model) (<= (Has-Parameter-Slot $X Machine_Beam_Unit_Weight) (Machine_Beam_Model $X)) (<= (Has-Parameter-Slot $X Machine_Beam_Section_Modulus) (Machine_Beam_Model $X)) (=> (Elevator.Mbeam $X $Y) (Machine_Beam_Model $Y))