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use of fuzzy logic in system dynamics ?

Posted: Sat Apr 12, 1997 9:01 pm
by M/S Challenger Cargo Carriers p
Please let me know any development in application of fuzzy logic in
system dynamics.

thanks

Ratan Saini
cccpl@del2.vsnl.net.in

use of fuzzy logic in system dynamics ?

Posted: Mon Apr 14, 1997 5:30 pm
by George Richardson
On could argue that "fuzzy logic" is used in almost every model system
dynamicists build. Repeatedly, thinking about aggregates "smoothes out"
influences that for an individual would be shaped like a step, exactly the
way the membership function in a fuzzy set is a smothed out version of the
membership function in a discrete set. And the teaching of weighting
functions for aggregate if-thens has been going on in the field probably
longer than fuzy set logic has been popular.

But I dont know of a specific applications of fuzzy logic to accomplish
some end in a system dynamics model that required the sophisticated
accomplishments of the fuzzy logic folk.

...GPR

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George P. Richardson G.P.Richardson@Albany.edu
Rockefeller College of Public Affairs and Policy Phone: 518-442-3859
University at Albany - SUNY, Albany, NY 12222 Fax: 518-442-3398
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use of fuzzy logic in system dynamics ?

Posted: Thu Oct 16, 1997 10:53 pm
by rjrahn@microtec.net (R. Joel Rah
George Richardson wrote...

>On could argue that "fuzzy logic" is used in almost every model system
>dynamicists build.

There is a fuzzy approximation theorem that says, essentially, that a TABLE
function is the same as a fuzzy decision rule. The basic idea is that an
input variable generates a fuzzy output. When you de-fuzzify the output (as
you have to do in fuzzy control systems), you get a (usually non-linear)
function. Now where have we seen that before....

R. Joel Rahn
rjrahn@pop.microtec.net