hello,
I have this question: in order for a model to be in equilibrium all levels must be unchanged and rates equal. How can i achieve this in the model i have uploaded?
thanks
Achieving equilibrium
Achieving equilibrium
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Re: Achieving equilibrium
Have you explained the problem correctly? If all levels remain unchanged, all you have is a set of constants, not a dynamic model.
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http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
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Re: Achieving equilibrium
I totally agree with you. but based on Sterman (Business dynamics... 2000) a model must start in equilibrium for testing purposes and then insert a change. maybe i misunderstood. in any case this simple model i uploaded cannot reach such a state right? is there something more for me to do?
many thanks,
irene
many thanks,
irene
Re: Achieving equilibrium
There's no feedback (yet) in this model, so equilibrium won't be terribly informative. However, it's very simple to set up - you just need to ensure that shipping rate = order receipt rate. One way to do that would be to have your PULSE TRAIN in order receipt rate start later than time 1, and to have demand start at the same time, so that initially the rates = 0. Again, this won't be very informative until there's some feedback in the model.
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