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conditional batch control

Posted: Thursday 06 March, 2014 - 22:19
by RPG
A six-week exhibition is modeled. During daytime exhibition tours of 10 visitors are formed until 16.00 PM. After 16.00 no new visitors are allowed entrance and the remaining visitors are put in groups until no visitors are remaining.
The visitors waiting for a tour are modeled by a queue followed by a server with no cycle-time. On the server a batch 1 in B out is formed with B:
if(mod(time,86400)>57600,
min(10,content(c)),
10
)
But this code doesn't work: the server is only emptied after each 10-th arrival in the server and if after 16.00 six visitors remain, they are not put in a group but remain there till the next day.
What should the code be?
I hope you can help
greetings,
Ruurd

Re: conditional batch control

Posted: Friday 07 March, 2014 - 12:06
by Nick
Hi Ruurd,

With the 1 in B out batching rule each time a product enters the Server, as many products as defined in the Batch input field leave the atom. The products are all copies of the atom that entered the Server. The Batch size is evaluated each time a product has entered the server.

What i would expect to happen with your code:
After 16.00PM min(10,content(c)) copies of the product are made. If a product enters the Sever the content of the server becomes 1. The batch size min(10,content(c)) is evaluated. The batch size is set to 1.

I'm not sure if you are using the right batching rule. Could you please attach your model?

Regards, Nick

Re: conditional batch control

Posted: Saturday 08 March, 2014 - 14:51
by RPG
opdracht2.docx
(12 KiB) Downloaded 320 times
opdracht2.mod
(23.71 KiB) Downloaded 320 times
Hi Nick,

Thank you for your reaction. You are right: in my question I wrongly wrote 1 in B out. In my model however there was written B in 1 out.
What my main problem is that I need a variable number of guides(=servers) (depending on the expected number of visitors, which varies in time) and on a multi service I can only put a fixed number as capacity and not a 4d expression. So what I did was an approximation by using a single server with zero cycle time and a 4d formula for a batch (number of guides) and then a server for the time of one tour.
In the attached files I give the problem and the model.
Greetings,
Ruurd

Re: conditional batch control

Posted: Monday 10 March, 2014 - 17:35
by Nick
Hi Ruurd,

There are of course different ways to approach this problem.

Returning to your initial question,
You can use another if statement in your if statement to form groups of 10 and a remainder group.

Regards, Nick