Hello,
Tony and Tom,
Attached you will find model "1" and model "2".
Model "1" has three sub-models, the output of stock " Dumping Done" in sub-model 1 is input as initial scope to sub2 " "work to Do 0). AND the output of sub 2, stock "spreading done " is input into sub 3 as initial value to stock "work to do 00). The results seems ok to me.
Now, Model 2 is assembling the three subs in a single model and the results are different. The problem is with the " Dumping Rate", Spreading rate", and `` compaction rate``. If you look at the output, you will see rates are not consistent means some times taking `100`and some times `0`. However, the rate is `100`.
Now, I need to have the behavioral of model 2 to be similar to model 1.
Please help.
SD model
Re: SD model
In model 2, your arrangement of the chain implies that "spreading rate" reduces "dumping done". So the meaning of "dumping done" is really "dumped but not yet spread".
A possible fix would be to change the equation for "task is done" at each stage to test whether the current stage is done, as you now do, :OR: if any subsequent stage is done.
Alternately, you could change the logic, so that completion of work is conditional on whether there is work to do, rather than on whether the work is done. I think this approach might actually lead to a clearer formulation.
A possible fix would be to change the equation for "task is done" at each stage to test whether the current stage is done, as you now do, :OR: if any subsequent stage is done.
Alternately, you could change the logic, so that completion of work is conditional on whether there is work to do, rather than on whether the work is done. I think this approach might actually lead to a clearer formulation.
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Re: SD model
tomfid wrote:In model 2, your arrangement of the chain implies that "spreading rate" reduces "dumping done". So the meaning of "dumping done" is really "dumped but not yet spread".
A possible fix would be to change the equation for "task is done" at each stage to test whether the current stage is done, as you now do, :OR: if any subsequent stage is done.
Alternately, you could change the logic, so that completion of work is conditional on whether there is work to do, rather than on whether the work is done. I think this approach might actually lead to a clearer formulation.
The work logic is as follow, nine scopes of activities (project activities), each activity will be dumped, then spread, compacted, and last quality check.
I tried the first logic and did not work, the second is not clear to me...please can you do the changes on the model??
Thank you.
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Re: SD model
I don't think anyone has the time to build your model for you.
If you upload your attempt and explain why you think it is not working, I'm sure we can take a quick look.
If you upload your attempt and explain why you think it is not working, I'm sure we can take a quick look.
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http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
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Re: SD model
HI
Why don't you try to simplify your problem and model, (say two levels or even one). There are two advantages: one is to make your problem easier to solve, the second is to attract more people to help you.
Regards.
JJ
Why don't you try to simplify your problem and model, (say two levels or even one). There are two advantages: one is to make your problem easier to solve, the second is to attract more people to help you.
Regards.
JJ
Re: SD model
Thank you for your respond and caring .LAUJJL wrote:HI
Why don't you try to simplify your problem and model, (say two levels or even one). There are two advantages: one is to make your problem easier to solve, the second is to attract more people to help you.
Regards.
JJ
I got the problem solved.