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processsystemincrementarena-simulation

Arena simulation - how to make entities leave the system after going through the same process twice?


I would like to create a simulation in Arena with a special condition.

The scenarios is as follows:

Entities arrive in the system, go through the process A and then arrive at a decision point where 80% of the entities leave the system and the rest 20% go through the same process A again. All of these 20% leave the system after being re-processed (a.k.a going through process A twice, but not 3 times or 4 times).

My question is:

How do I model these 20% entities to leave the system after being processed 2 times?

Thank you!

I tried to look for solutions using Assign module to increment the number of times an entity passes through the process, but couldn't make it work.


Solution

  • To do this, you need to do three things in your model.

    1- Add and assign module before process A and give an attribute named "reprocessed" a value of 0. 2- Add another decide module before the existing one and send the entities with the value of the "reprocessed"=1 to exit. 3- Add an assign module at the exit point of the (second) decide module that sends enteritis back to "process A" and gives a value of 0 to the attribute "reprocessed".

    Applying these changes, when entities arrive at first assign module receives a value of 0 for attribute "reprocessed" and then goes through process A and B. Then reaches the first decide module and continues its way to second decide module. Assume that this entity needs to get back to process A. Then it crosses the assign module that gives the value of 1 to "reprocessed". Then it goes to process A and B again and when arrives at first decide module, since it has the value of 1 for "reprocessed", then it will be sent to exit.