I want to get the WIP value of the compared with lines..

I want to compare with some similar but three different lines.

Line #1 = 10 processors Without any buffer and with same constant Standard Time.
Line #2 = 10 processors without any buffer and with normal distribution ST.
Line #3 = 10 proc. with 9 buffers and with normal distribution ST.

I want to compare with the lead times, WIP and throughput etc.

But the value of WIP is not correct. I want to know the reason.
And I want to display the each line WIP trend in dashboard not total WIP.
How can I do it?

Thanks.

P.S
If the model will be displayed normally, the MCs should be changed to processor object.

Hello syseo,

you run in a problem most of my students run into, too.
You use only one random stream. Each statistical distribution should use a unique random stream.

if you want to update the processtime in the label of your items you can use the following source code in the Process Time

double processtime = normal(Standard_Time,ST_variation,1);
inc(label(item,"TotalProcTime"),processtime);
return /**/processtime/**direct*/;

You don't have to set the creationtime of your items in a label, you can get this time with the command getcreationtime(obj). This works even with the items.

The increasing staytime you see in your last line, I would expect too. The process time varies roughly between 1 and 19 seconds. The accumulation is the natural effect of the queues.

Jörg

WIP is not correct in the lines.
I subtract the output of last processor from the input of the first processor.
But the value is different from the existing items in the line.

What's the problem?

And how can I compare with the WIP of each lines?

Syseo,

What appears is happening is that you are subtracting the items one process earlier than they will enter the sink, which is the actual time they are removed from your line and WIP. I edited the on entry code to Que_Line 1 to the following and I believe this is the result you are looking for.

setlabelnum(current,"WIP_Qty",getoutput(centerobje ct(current,2))-getinput(outobject(current,1)));

Ryan

Hello Syseo,

I build a model with visual tool as container.
The sum of all items is the contentunder(obj visual tool) - (objects in the container). This value is set to a time-weighted trackedvariable, e.g. on exit of the last processor in the line.

That's work fine.

Jörg

LineBufferTest_Question_JV.fsm

Dear Jorg. Thank you but...

The WIP count quantity is not same with the quantity to be displayed on screen.

The line 1 : 9 but the screen displays 8 items.

What's the problem?

I attached the snap captured.

You can find it when run and stop ...

Thanks.

I have some troubles or bugs(?) when get the values of them.

I found the differences of them between the counted values and the screen display.

What's the problem of them?

I attached the screen captured and the model.

I want to receive anyone's help.

Syseo,

Ryan is correct. Use the Step button. You will see that for a moment your line has only 9 items. The OnEntry event of of the leading item entering Que_Line1 (and the Sink) comes before the event which releases the trailing item from the Source... even though they occur at the same "time", one has to be first. Think of it as a single processor, the first needs to leave in order for the next to be allowed to enter. This means that for a moment the processor has a content of zero. You are updating your WIP label in that moment when your system contains one less than its actual capacity.

You need to update a WIP count on both entry AND exit of a system, otherwise you are vulnerable to this reality of discrete event simulation.

Thank you for your Kind explanation, Kris and Ryan.

I have understood your meaning.
It's very interesting.

Thanks a lot.