The structured phase of concurrency

This extended abstract summarizes the state-of-the-art solution to the structuring problem for models that describe existing real world or envisioned processes. Special attention is devoted to models that allow for the true concurrency semantics. Given a model of a process, the structuring problem deals with answering the question of whether there exists another model that describes the process and is solely composed of structured patterns, such as sequence, selection, option for simultaneous execution, and iteration. Methods and techniques for structuring developed by academia as well as products and standards proposed by industry are discussed. Expectations and recommendations on the future advancements of the structuring problem are suggested.

We still don’t know how much BPMN is enough – but we are getting closer

Process models expressed in BPMN typically rely on a small subset of all available symbols. In our 2008 study, we examined the composition of these subsets, and found that the distribution of BPMN symbols in practice closely resembles the frequency distribution of words in natural language. We offered some suggestions based on our findings, how to make the use of BPMN more manageable and also outlined ideas for further development of BPMN. Since this paper was published it has provoked spirited debate in the BPM practitioner community, prompted the definition of a modeling standard in US government, and helped shape the next generation of the BPMN standard.

On structured workflow modelling

While there are many similarities between the languages of the various workflow management systems, there are also significant differences. One particular area of differences is caused by the fact that different systems impose different syntactic restrictions. In such cases, business analysts have to choose between either conforming to the language in their specifications or transforming these specifications afterwards. The latter option is preferable as this allows for a separation of concerns. In this paper we investigate to what extent such transformations are possible in the context of various syntactical restrictions (the most restrictive of which will be referred to as structured workflows). We also provide a deep insight into the consequences, particularly in terms of expressive power, of imposing such restrictions.