Food Web Model Question
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- Vensim version: PLE
Food Web Model Question
Hi there, I am constructing a food web model in Vensim PLE vs 7.2a and I am struggling to figure out what delay function to use. The delay would be an increase/decrease in a certain stock due to a seasonality change. So it would be a fixed amount at say every 4 months. Any advice and help would be greatly appreciated.
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- Super Administrator
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Re: Food Web Model Question
Can you use a pulse train? It's difficult to say more without seeing the model you are working on.
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http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Re: Food Web Model Question
When I hear seasonality, I think of a SIN wave, rather than a delay. A PULSE TRAIN would be a good discrete substitute.
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Advice to posters (it really helps us to help you)
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Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
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