occurs before

This property identifies the relative chronological sequence of two temporal entities. It implies that a temporal gap exists between the end of A and the start of B. This property is only necessary if the relevant time spans are unknown (otherwise the relationship can be calculated). This property is the same as the "before / after" relationships of Allen’s temporal logic (Allen, 1983, pp. 832-843).

occurs before

This property identifies the relative chronological sequence of two temporal entities. It implies that a temporal gap exists between the end of A and the start of B. This property is only necessary if the relevant time spans are unknown (otherwise the relationship can be calculated). This property is the same as the "before / after" relationships of Allen’s temporal logic (Allen, 1983, pp. 832-843).