  Simple Temporal Networks (STNs) provide a powerful and general tool for
representing conjunctions of maximum delay constraints over ordered pairs of
temporal variables. In this paper we introduce Hyper Temporal Networks (HyTNs),
a strict generalization of STNs, to overcome the limitation of considering only
conjunctions of constraints but maintaining a practical efficiency in the
consistency check of the instances. In a Hyper Temporal Network a single
temporal hyperarc constraint may be defined as a set of two or more maximum
delay constraints which is satisfied when at least one of these delay
constraints is satisfied. HyTNs are meant as a light generalization of STNs
offering an interesting compromise. On one side, there exist practical
pseudo-polynomial time algorithms for checking consistency and computing
feasible schedules for HyTNs. On the other side, HyTNs offer a more powerful
model accommodating natural constraints that cannot be expressed by STNs like
Trigger off exactly delta min before (after) the occurrence of the first (last)
event in a set., which are used to represent synchronization events in some
process aware information systems/workflow models proposed in the literature.
