A state-based intention driven declarative process model

Declarative process models support process flexibility, whose importance has been widely recognized, particularly for organizations that face frequent changes and variable stimuli from their environment. However, the currently dominant declarative approaches lack expressiveness for addressing the process context (namely, environment effects) and leading its execution towards a goal. This paper proposes a declarative model which addresses activities as well as states, external events, and goals. The model is based on the Generic Process Model (GPM), extended by a notion of activity, which includes a state change aspect and an intentional aspect. The achievement of the intention of an activity may depend on events in the environment and is hence not certain. The paper provides a formalization of the model and describes an execution mechanism. It emphasizes the usefulness of specifying the intentional aspect of activities, by using it as a basis for semantic validation of the model at design time and for a planning module that can guide execution at runtime. These are illustrated by an example from the medical domain.