Alternative Process Modeling langugues

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Alternative Process Modeling langugues
UML activity diagrams
Event-driven process chains
System-specific languages like Staffware will
follow later...
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UML

• Unified Modeling Language (Booch, Jacobson, and
  Rumbaugh)
• Diagrams in UML
• Class diagrams
• Object diagrams
• Use case diagrams
• Sequence diagrams (P)
• Collaboration diagrams (P)
• Statechart diagrams (P)
• Activity diagrams (P)
• Component diagrams
• Deployment diagrams
• Four of the ten diagrams can be used to describe
  process-related aspects.
• The activity diagrams are close to workflow
  languages and borrow elements from Petri nets.

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UML overview
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Basic concepts
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Basic routing mechanisms (1)
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Basic routing mechanisms (2)

Do not use this in this course!
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Example
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Event-Driven Process Chains (EPCs)

• German Ereignisgesteuerte Proceßkette
  (EPK)(Keller, Nüttgens, Scheer 1992)
• Used in
• SAP reference models,
• SAP R/3 Business Workflow (EPC views),
• ARIS (IDS Prof. Scheer),
• LiveModel/Analyst (Intellicorp. Inc.)
• Elements

Every function/event has max. 1 input/output arc!!
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EPC (Semantics)
?
?
XOR
?
Initial/final functions have input/output place
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EPC (Semantics connectors)
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EPC (Example)
Note the multiple start and end events
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EPC (Connected connectors)
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EPC (Solution)
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EPC (Solution, top)
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EPC (Solution, bottom)
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EPC (Find the error)
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Good and bad constructs
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OR splits and OR joins

• OR split can be mapped onto an AND-split followed
  by XOR-splits.
• OR join has the "bus driver semantics" (this
  causes a paradox and other problems).

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Travel expenses process in SAP R/3 reference model
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Dealing with EPCs

• Informal, i.e., no clear semantics
• To map an EPC onto Petri nets
• Remove all OR-splits and OR-joins, i.e., refine
  them by AND and XOR (interpretation is needed).
• Resolve the fact that there can be multiple
  source and sink events by refinement and the use
  of triggers (interpretation is needed).
• (i.e., first interpret the process and then
  translate)

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EPC (Extensions, ARIS)
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ARIS Toolset (IDS Scheer)
SAP R3 reference models
EPC
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Travel expenses process
subprocess
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EPC view in SAP Business Workflow, SAP AG
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In this course you are expected to be able ...

• to read and understand UML activity diagrams,
• to map simple UML activity diagrams onto the
  notation of this course (only control flow),
• to read and understand EPCs,
• to map any EPC onto the notation of this course
  (only control flow),
• to map simple examples onto the EPCs!