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20.6 Related Work
As explained in the introduction the approach presented here is closely related to systems in the WfMS tradition as well as the Groupware tradition. In the WfMS domain a number of projects have tried to address the issues of adaptiveness and flexibility (Kammer et al. 2000; Norman et al. 1996; Agostini and De Michelis 2000; Ellis and Keddara 2000). However, all of the approaches aim at completely specifying the process before it is started using some formal method (e.g., Petri nets) and adapting them when exceptions occur. They typically do not allow the execution of partially specified or abstractly specified process descriptions. At the other end of the frontier, a number of CSCW projects and Groupware tools have addressed the support for highly flexible processes.
Figure 20.9: Related work
The biggest problem of all related projects, however, is the impermeability of processes across the specificity frontier. As can be seen in figure 20.9, processes that get started in one category of support system are stuck in that type of support. Thus the support for an emergent process, for example, stays trapped in an ad hoc system, though its process structure may have emerged during a first part of its execution. Even systems basing on event condition–action rules (ECA), which are typically used for constraint preservation or AI-planning systems, do not allow for mobility across the specificity frontier.
I know of three exceptions: ProZessware (ONEstone 1998), Bramble (Blumenthal 1998), and FreeFlow (Dourish et al. 1996). ProZessware allows embedding Lotus-Notes discussions into well-specified work flows. However, these embedded discussions have to be prespecified, and the actual process structure is fixed. Bramble divides activities into well specified and unstructured. Similar to ProZessware it allows composing semistructured activities from both well-specified and unstructured activities. In addition it provides a rich mechanism for providing process context. Unlike the system presented here, though, it does not seem to allow for run-time transformations of activities from well specified to unstructured, and vice versa. FreeFlow provides a highly unspecified and dynamic and a highly specified and routine mechanism to break the predefined constraints, which specify the work flow. Once a constraint is broken, however, its guidance is lost for the process. Thus the system only allows a one-time reduction of specificity of a process description during run-time. The work presented here is set apart from other projects by proposing a novel well-grounded approach to enabling the mobility of a process instance across the specificity frontier during run-time.
