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Technology has always found its greatest consumer in a
nation's war and defense efforts. Since the last attempts at a
"Star Wars" defense system, has technology changed
considerably enough to make the latest Missile Defense
initiatives more successful? Can such an application of
science be successful? Is a militarized space inevitable,
necessary or impossible?
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(14133 previous messages)
rshow55
- 04:07pm Sep 29, 2003 EST (#
14134 of 14145) Can we do a better job of finding
truth? YES. Click "rshow55" for some things Lchic and I have
done and worked for on this thread.
http://talk.guardian.co.uk/WebX?14@@.ee7a163/483
includes some petty pictures - and dialog about them Fractal
Images http://www.softsource.com/softsource/fractal.html
http://www.softsource.com/softsource/m_cndl.gif
http://www.softsource.com/softsource/m_pine.gif
http://www.softsource.com/softsource/m_pine.gif
http://www.softsource.com/softsource/m_trieye.gif
Control systems out of adjustment oscillate
uncontrollably or diverge - like fractals - they do not
close. But things can be adjusted so that order, symettry,
and harmony for a purpose are attainable. People, of course,
do this often - when they take care, and know enough to do
so.
Problem is, when people face complicated circumstances -
often they do things backwards - and things explode.
http://talk.guardian.co.uk/WebX?14@.4a90f6e9/85
A lot of plots look like images you see in many fractals -
and some plots of this kind that are practical are shown in
books like
Analysis of Nonlinear Control Systems by Dunstan Graham
and Duane McRuer 1961 - Dover ed 1971
I quote some from that fine book.
7896 http://forums.nytimes.com/webin/WebX?8@13.h1YTbtNkJG4.2636994@.f28e622/9421
7897 http://forums.nytimes.com/webin/WebX?8@13.h1YTbtNkJG4.2636994@.f28e622/94227
7897 http://forums.nytimes.com/webin/WebX?8@13.h1YTbtNkJG4.2636994@.f28e622/9423
"Some of the most unpleasant surprises of which nonlinear
control systems are capable are
1. divergent instability
2. limit cycles
3. multiple equilibrium points.
For large perturbations of nonlinear systems that are not
controlled at a higher level, divergent instability is the
rule - multiple quasi-equilibrium points are not surprises,
but the overwhelming expectation - and limit cycles are the
best, as a practical matter, that anybody can actually hope
for - or can actually get. Very, very often - what happens
looks fractal.
But with care - and switching - designed for particular
cases and calibrated - excellent performance can be achieved.
It isn't likely to happen by accident, though.
- Cantabb - jorian - you've mastered the "art" of hitting
things with a big hammer - to make sure nothing can converge.
I'm not sure you could do better if you tried.
I'm out for a little while.
jorian319
- 04:17pm Sep 29, 2003 EST (#
14135 of 14145) The dogmatism is all on the side
that maintains there is no global climate effect ...Anyone who
has visited a city like LA on a nice smog filled day knows
that's not true. -amzingdrx
Well, Robert, if you ever come back, maybe you could
respond to my post about Langley and control. The lesson of
the Langley/Wright Brothers saga includes the point that
controls are not necessarily fractal - in real-life
engineering, YOU CAN'T JUST MAKE THINGS BIGGER!
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