Metamodellbasierte und hierarchieorientierte ... - RosDok

Abstract
This work presents new metamodel-based approaches for workflow or business process modeling. Two
different ways for business process modeling are followed with a declarative and a hiearchical one that are
not common nowadays. The main advantage for the declarative language lies in a better flexibility and the
hierarchical approach promises stuctured models that are better to be understood. Therefore, the work is
divided into two parts that comprises two chapters respectively to introduce the design and runtime for each
language.
In the first part a declarative metamodel-based approach for business process modeling, execution and
analysis is introduced. With the declarative background, we follow a more flexible way of modeling
workflows compared to the traditional, imperative languages by giving more execution possibilities to the
user by default. Different models for data, organization and workflows are used and mutually connected
based on the presented metamodel. The developer creates them in the UML tool while static consistency
properties are checked by OCL invariants. Afterwards, they can be executed based on the tool realizing
parts of the UML action semantics. A plugin for the UML tool provides an appropriate interface to the
user that presents the workflow instances at the runtime. She can validate the dynamic model properties
with the plugin by executing the developed models. They are adaptive and can be changed or developed
at runtime. Lastly, the developer can use OCL for process mining purposes to discover properties of the
executed process scenarios.
The second part introduces a hierarchical, decomposition-oriented approach for modeling workflows. Task
trees are an established modeling approach in the field of Human Computer Interaction that represent
user-centered, goal-focused activity models. In contrast to established workflow languages, one structured
model captures several abstraction levels of a workflow, that offers benefits for model understandability.
Some advantages and shortcomings for this modeling approach are discussed in the context of business
process modeling. Transformation rules show connections between UML activity diagrams and task models.
In addition, a metamodel-based approach and the tool from the first part of this work are used to define
task models. The precise metamodel enables the developer to find soundness problems and also execute
these models employing the UML tool. Furthermore, a Workflow Management System is introduced on the
basis of task models to provide a distributed workflow execution. This system implements existing and new
language elements for task models.