Workflows are a technology to structure work in functional, non-overlapping steps. They defineudnot only the order of execution of the steps, and describe whether steps are executed inudparallel, they also specify who or what tool has to fulfill which step. Workflows offer the possibilityudto automate work, to increase the understandability of processes, and they ease theudcontrol of process execution. The tools to manage workflows, so called workflow managementudsystems (WfMSs), are traditionally rigid as they separate workflow definition done at build timeudfrom workflow execution done at run time. This makes them ill-suited for managing flexible andudunstructured workflows. In this thesis, we focus on the support of flexible processes in eHealth,udwhich are affected by more foreseen than unforeseen events. To bridge the gap between rigidudWfMSs and flexible workflows, we developed a concept for dynamic and context-aware workflowudmanagement called Flexwoman. Although our focus lies on flexible eHealth processes,udFlexwoman is a generic approach that can be applied to several different application domains.udFlexwoman supports the usage of context information to adapt processes automatically at runudtime to foreseen events. Processes can also be manually adapted to handle unforeseen events.udTo achieve this flexibility, context information from different sensors is unified and thus can beudanalyzed in the same way. The analysis and adaptation of workflows is executed with a rule engine.udA rule engine can store, reason about and apply knowledge automatically and efficiently.udRules and application logic are separated, thus, rules can be changed during run time withoutudaffecting application logic or process description. Workflows are internally described by HierarchicaludColored Petri nets (HCPNs) and executed by a HCPN execution engine. HCPNs allow foruda deterministic execution of workflows and can represent workflows on different levels of detail.udIn summary, in Flexwoman, significant context changes (events) trigger automated adaptationsudthat replace parts of the workflow by sub workflows, which can in turn be adapted. The adaptationsudand the rules for context-aware adaptation are saved in the organizational memory forudlater reuse. Flexwoman’s event based behavior facilitates proactive adaptations instead of onlyudallowing for adaptations while entering or leaving a task. Replacements are not bound to specialudplaces defined at build time but each part of the workflow, which has not been executed yet, canudbe replaced at run time. We implemented and evaluated the concept. The evaluations showudi) that all required functionality is available, ii) that the system scales with a growing number ofudrules, and iii) that the system correctly handles failure situations.
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