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Re: chokes



Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>" <evp-at-pacbell-dot-net>

> After twenty years as a systems simulation and forecasting engineer in the
> pipeline industry, I am somewhat aware of the strengths and weaknesses of
> simulator packages. They work quite well for deterministic steady state
systems
> and quasideterministic periodic dynamical systems and poorly for chaotic
> dynamical systems. I also happen to believe (and it IS a belief) that chokes
> probably have too many disadvantages that outweigh any possible benefits. I
> also believe that simulation applied to chaotic dynamical systems is, as
one on
> my numerical methods professors used to say, "The fine art of pushing a dead
> mouse through a maze and carefully recording what it does." Put in more
prosaic
> terms, the region of stability of the model is never exactly coincident with
> the region of stability of the system it represents. Usually, simulations are
> only tested against reality when they say that something will work, not when
> they say it won't.
> In chaotic systems, non-linearities are as likely to cascade as they are
to die
> out, and this is where second-order approximations can run into trouble,
still
> leaving room for experimental work to verify the models.
> 
> Matt D.

	I've done quite a bit of modeling using Electronics Work Bench (I'm not
a Spice whiz!) and it clearly shows the kind of chaotic behavior I've
observed when playing with the gap width, capacitor size, and NST
primary voltage.  Beyond that I'll leave it the experts.  I like your
professor's quote!

Ed