См.: логический и-соединитель.
logical 'and' connectorlogical 'and' connector - - A symbol shaped like an ellipse used in thinking processes sufficiency-based logic diagrams to indicate lateral dependency among contributing causes, i.e., that all entities whose exiting arrows are encompassed by the logical 'and' connector must exist in order for the effect to exist.
Usage: The logical 'and' connector is used in the following logic diagrams: the current reality tree, future reality tree, negative branch reservation, and transition tree. The ellipse is drawn across the arrows from two or three entities to denote that they all must exist if the designated effect is to occur. In other words, removal of any one of the causes covered by the ellipse precludes the indicated effect from occurring.
Illustration 1: The following logic diagram is verbalized: If 10 I eat too much and 20 I don't exercise then 30 I gain weight.
Illustration 2: If 60 I have fuel and 70 I have a heat source and 80 Oxygen is present then 90 I can create a fire. If any of these three conditions do not exist then the fire cannot be started.