Gregor Joeris

Towards Flexible and High-Level Modeling and Enacting of Processes

Process modeling and enacting concepts are at the center of workflow management. Support for heterogeneous processes, flexibility, reuse, and distribution are great challenges for the design of the next generation process modeling languages and their enactment mechanisms. Furthermore, flexible and collaborative processes depend also on unpredictable changes and hence require human intervention. Therefore, high-level process modeling constructs are needed which allow for an easy, adequate, and participatory design of workflows. We present a process modeling language which covers these requirements and is based on object-oriented modeling and enacting techniques. In particular, we outline how tasks and task nets are specified at a high level of abstraction, how flexible and user-adaptable control and data flow specifications are supported, and how reuse of workflow models can be improved. The approach is characterized by the uniform and integrated modeling of workflow schema and instance elements as objects and by the integration of flexible rule-based techniques with the high-level constructs of task graphs. Finally, we present our object-oriented approach for the distributed enactment of workflow models: A workflow is directly enacted by task agents which may be treated as reactive components, which interact by message passing, and whose execution behavior is derived from the context-free and context-dependent behavior of the tasks defined in the workflow schema.

Change management needs integrated process and configuration management

Change management is a core problem of software development. Management of changes means managing the process of change as well as managing all artifacts of an evolving software system. Both challenges have been focused extensively in the field of software process modeling and software configuration management, respectively. In this paper, we motivate that change management needs an integrated approach to process and configuration management. A fundamental prerequisite to provide such a comprehensive support is the integration of the underlying representation formalism of process and version models. To cope with this problem, we propose a conceptual framework to provide a common conceptual basis of process and version modeling concepts and identify the requirements for comprehensive process support for change management. Furthermore, we classify and evaluate different approaches of how to integrate process and version models from a conceptual point of view.

Cooperative and integrated workflow and document management for engineering applications

Engineering workflow management has to cope with a great variety of processes. Well structured and a priori defined activities are mixed with creative, less structured, and continuously evolving process steps. The classical coordination support provided by workflow management systems has to be enhanced to cope with dynamic, product centered, and cooperative processes. We concentrate on cooperation support within workflow management on both document level and workflow level. First, we propose an integrated and flexible approach to process and document management which is based on an object oriented modeling framework. We outline how different kinds of processes can be supported on this basis. Finally, we introduce an approach for flexible control and data flow modeling which supports cooperation on the workflow level and takes versioning and different forms of data interchange between activities into account.