Search found 4 matches

by "Wayne Wakeland"
Sat Mar 03, 2001 7:15 am
Forum: SD Mailing List Archive
Topic: What is system dynamics?
Replies: 1
Views: 2636

What is system dynamics?

SD2374 responded to a similar question. You can find this post at http://www.optimlator.com/master/99D/2759.htm If you search on this site for "discrete" you will find a number of items on this subject. Wayne Wakeland Associate Professor of Systems Science Portland State University Portlan...
by "Wayne Wakeland"
Fri Apr 14, 2000 6:59 am
Forum: SD Mailing List Archive
Topic: Epidemic and S-Shaped
Replies: 11
Views: 12189

Epidemic and S-Shaped

John The balancing loop is Healthy people to catching illness to Healthy people. If you have no Healthy people, none can flow out. When you have interacting loops, loop analysis gets tricky, which is why we "operationalize" models (in Barry Richmonds terminology) and run them to help us un...
by "Wayne Wakeland"
Wed Nov 10, 1999 7:57 pm
Forum: SD Mailing List Archive
Topic: bullwhip effect on the supply chain.
Replies: 5
Views: 14412

bullwhip effect on the supply chain.

Is the "bullwhip effect" being discussed qualitatively different from the
dynamics of the beer game with ill-conceived replenishment rules and long
delays?

Wayne Wakeland
Adjunct Professor of Systems Science
Portland State University
wwakeland@uswest.net
by "Wayne Wakeland"
Wed Oct 27, 1999 10:42 pm
Forum: SD Mailing List Archive
Topic: Dividing by dt
Replies: 0
Views: 9256

Dividing by dt

While I too abhor the general idea of dividing by dt in a rate equation, I have found it hard to avoid when modeling such systems as a simple home heating system. One needs a way to model whether the furnace is off or on. I use a stock that was either 0 (off) or 1 (on). To turn the furnace on when i...