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FMC Process Diagrams model processes in a system. transitions and places are the main ingredients of a FMC Process Diagram. Transitions represent steps in the process and places represent states within the process. Edges connect places and transistions. With these basic elements you can easily compose complex processes including conditions, loops and concurrent sub-processes. |
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Several variants of petri nets exist. Because of that, the following description will only explain the common ideas behind petri nets, without discussing any particular variant in detail. If you want to know more about petri nets, feel free to contact us.
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The competency indicates which agent is responsible for this part of the process. Each place and each transition needs to belong to exactly one competency, but different parts of the process can belong to different competencies. Edges are the only elements that may cross the boundaries of a competency. |
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Each place represents a partial state of the system. Places can hold tokens. If a place holds a token, it is tagged. All tagged places together represent the state of the process. At least one place must be tagged initially. Starting with this place the process can be simulated by tracking the flow of the tokens. |
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Edges transport tokens. Every edge connects a place with a transition or vice versa. The direction of the edge indicates the direction of the token flow. |
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Transitions represent process steps. A transition becomes active when all its input places are tagged and all its output places empty. When the transition is active, it can fire. Upon firing, the transition removes one token from each input place, executes the process step and places a new token in each output place. |
Apart from the basic elements the ARCWAY Cockpit offers several macro templates that combine the basic elements to define common advanced structures:
Sequence Step
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Conditional Choice
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Loop
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Concurrency
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An edge creates causality relations between transitions and places.
The plan element that is anchored to the arrow succeeds the plan
element that is anchored to the unmarked end of the edge. The transition "B" is the successor of the transistion "A" in the example. |