Time of arrival between batches

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Ludovic S2 asked Apr 28, '19 Jordan Johnson commented May 2, '19

Time of arrival between batches

Hi,

I would like to measure the time of arrival between batches (both the mean and variance). The batches are triggered by the racks and created in processor 3. Then they flow from queue 1 right to queue4. I was wondering if someone knows how to measure the time of arrival between batches? Both the meand and variance.

Is there maybe some way where I can see the time logging from all the messages send from the racks? Based on this I would be able to calculate the time of arrival between batches.

Thank you in advance

Kind regards

model-with-variation.fsm

Ludovic

Software Version:

FlexSim 19.0.2

rack batch processing arrival time

model-with-variation.fsm (42.3 KiB)

· 1

tannerp commented · Apr 29, 2019 at 05:19 PM

Your question seems to be related to this one. It would help if you could simplify the model so it's easier to dissect what's going on.

In order to track the time between batches, I created a script on a trigger of Queue 1. This isn't anything fancy, but essentially it takes the current time and subtracts the time of the last batch collected then outputs that value. There appears to be multiple batches collecting within a second of each other, which may or may not be what you are intending. Either way, the information in the Output Console should help you determine if you have the right number of batches at the right times.

18805-model-with-variation-1.fsm

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18805-model-with-variation-1.fsm (42.8 KiB)

Answer 1 · 2019-05-01T00:14:04Z

Jordan Johnson answered May 1, '19 Jordan Johnson commented May 2, '19

Here's a model I made that gathers the statistics you wanted:

model-with-variation-with-stats.fsm

It uses a Process Flow to listen to when the batches are made, and it measures the time between batches, per rack.

Then I used a Statistics Collector to log those values, so that every inter-batch time is recorded in the table.

Finally, I used a Calculated Table to calculate the mean and variance of the the inter-batch time by rack.

batch-mean-variance-by-rack.png (6.9 KiB)

model-with-variation-with-stats.fsm (46.9 KiB)

· 2

Ludovic S2 commented · May 01, 2019 at 07:20 AM

Hi jordan,

Thank you for your answer. It looks great, but I would need to know the behaviour arrival of the batches in queue1. This way I would be able to evaluate with what kind of queue I am dealing here (f.i. M/G/1 or something else).

Kind regards

Ludovic

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Jordan Johnson ♦♦ Ludovic S2 commented · May 02, 2019 at 11:04 PM

In the model I created, I measure the time between when a batch is created, and when the next batch is created. Is that the correct way to look at this problem? I also broke down the statistics by Rack that sent the message. If you don't want that, and just want the overall average, you can edit the query in CalculatedTable1 to say this:

SELECT AVG(Time) AS Mean, VAR(Time) AS Variance
FROM StatisticsCollector1

That will update the table to look as follows:

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batch-variance-overall.png (2.5 KiB)

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