Arriving Entity Types are Randomly Distributed

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Arriving Entity Types are Randomly Distributed

The distribution of entity types that arrive in the system is random.

The model used for this example, as well as all of the modeling "how-to" examples, can be found in the ProModel Solutions Café (http://www.promodel.com/solutionscafe/howto/).

Solution

Define all the different possible entity types that can arrive.
Define a generic entity type representing anyone of the possible arriving entities before it is known what type it will be.
Define a “dummy” arrival activity where generic entity type will arrive. This activity serves no other purpose than to provide a point for determining what the entity type is.
Define an arrival from the generic entity type to this dummy activity.
From the dummy activity define percentage routings to the “real” arrival activity for each of the entity types that can arrive and specify the percentage of time that the arrival is of that entity type.
In the New Name field of each percentage routing dialog, specify the entity type for that percentage.

Example

Job Orders arriving at a Dispatch desk in a job shop may be one of three types. 60% of the time they are Type A, 30% Type B, and 10% Type C. The interarrival time of jobs is exponentially distributed with a mean of 10 minutes.

Solution

Notice that a generic Job entity arrives at a dummy Distribution activity where each of the entity types is randomly determined based on the arrival percentage breakdown.