Arena modeling

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Arena modeling
Conceptual model can be converted into Arena
model. Arena model connected building
blocks. Building blocks must be parameterized.
Arena interface demo
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Basic blocks
Create / Process / Dispose building blocks.
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Adding resources
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Splitting transitions
Seize two resources, release one when finished.
Not directly possible in Arena Seize Delay
seize and keep all Seize Delay Release seize and
return all. Implementation split!
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Ferry implementation (ARENA)
Split marked transitions.
Add "case" class for A2B and B2A. Create once, do
not dispose.
Resources cannot be added.
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Parameterization
Arena building blocks are parameterized. Default
parameters are set when installing
blocks. Resource consumption/production
parameters inferred from conceptual model.
Parameters to be added - arrival distribution
for create blocks (often negexp with a certain
intensity), - duration for process blocks
(sometimes 0 for blocks that result from
splitting.
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Testing
After model construction, animated simulation is
done. Press ? button and observe. Correct syntax
errors. Unexpected results adapt or explain.
If found correct, choose Run Setup, then
Replication parameters tab. Select a moderate
replication length and then press ??, wait until
completion and examine the report.
Standard report queue lengths for
resources, processing times for entities.
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Decide block
Alternative paths
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Assign block
Assignment - attributes (per entity) - variables
(global) "ordinary" programming
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Other blocks
In some cases, the simulation should report on
special data (e.g. expressions involving
attributes and variables). This can be achieved
by including the Report block.
Separate block is used for duplication of
entities. Batch block is used for grouping
entities.
For other Arena blocks, see the Arena book W.D.
Kelton, R.P. Sadowski, and D. Sturrock. Simulation
with Arena, 3rd ed. McGraw-Hill, New York, 2004.
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Classwork
A factory fabricates two types of products, X and
Yand has (multiple) machines of types A,B and C
respectively. Orders for product X have to pass
through A and then C. Orders for Y have to pass
through B and then C. The machine types A and B
are different configurations of the same machine.
It is possible to reconfigure a machine from type
A into type B and vice versa. If no cases are
waiting for resource A and the queue length for
cases waiting for resource B exceeds N, a machine
of type A is reconfigured to type B. If no cases
are waiting for resource B and the queue
length for cases waiting for resource A exceeds
M, a machine of type B is reconfigured to type
A. Give conceptual model and Arena implementation.
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Parameters
interarrival times X,Y 1.0, resp. 0.85
minutes. machines A, B and C available 2, 2, 4
(initially). Processing duration 1.6 minutes per
A/B step and 1.8 minutes for any C
step. Reconfiguration 4 minutes (both A2B and
B2A). Find most effective N, M .