More precise descriptions of temporal relations within task models

Abstract

Task models are more and more accepted as a prerequisite for agood design of interactive systems. In the existing approaches, the description of temporal relations between the subtasks corresponds to the hierarchical decomposition of a task. This paper proposes a separate specification of actions and goals constituting tasks where an action model called simple action model describes the hierarchical and sequential character of the task. An extension of the simple action model by additional temporal constraints is suggested. Thus, a more general models can be specified which can be adapted to actual conditions. The adapted action model allows a more precise modelling of temporal relations between subactions. This approach can contribute to a more flexible task modelling.