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From: willett@cbnewsl.cb.att.com (david.c.willett)
Subject: Re: The actual quote from the Post AAS article
Date: Tue, 16 Mar 1993 14:54:22 GMT
Date: 1993-03-16T14:54:22+00:00	[thread overview]
Message-ID: <1993Mar16.145422.14034@cbnewsl.cb.att.com> (raw)
In-Reply-To: 1993Mar15.193135.29340@seas.gwu.edu

Mike Feldman wrote:

	{Initial Discussion about ATC Systems deleted}
>>
> Hmmm. My sources around FAA tell me that the main reason for Europe's having
> _fielded_ new ATC systems - In Ada - is that European air traffic is
> simply less dense than that of the US; there are fewer planes flying fewer
> corridors into fewer big airports. I know little about the internals of
> ATC systems, but general intuition and experience tell me that problems
> in this kind of system scale up perhaps linearly: 4 times the traffic 
> results in a system 4 times as complex. Maybe the "big O" is even worse.
> It would be nice if it were sublinear, but somehow I doubt it. 
>
	{Some Conclusions and Hopes for "lessons learned" deleted} 
> 
> Mike Feldman

It seems to me that the complexity of an ATC system would increase similarly
to the N-body problem from physics.  An example of such a problem is to
predict the motion of an electron travelling through a distribution of 
charges.  If memory serves, that problem is O(X**n) where N is the number
of charges and X is the number of electrons.
-- 
Dave Willett          AT&T Federal Systems Advanced Technologies
A Theoretical Physicist is one whose existence is postulated to make
the numbers balance, but is never observed in the laboratory.



  reply	other threads:[~1993-03-16 14:54 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
1993-03-11 19:21 The actual quote from the Post AAS article Mike Berman
1993-03-11 21:30 ` Robert I. Eachus
1993-03-11 23:47   ` Mike Berman
1993-03-12 23:25   ` Michael Feldman
1993-03-12 23:33   ` Michael Feldman
1993-03-11 21:35 ` Michael Feldman
1993-03-15 10:59   ` Kevin Rigotti
1993-03-15 19:31     ` Michael Feldman
1993-03-16 14:54       ` david.c.willett [this message]
1993-03-17 22:02         ` Gregory Aharonian
1993-03-18 17:49           ` david.c.willett
1993-03-12 16:15 ` Tom Pole
1993-03-12 23:15   ` Charles H. Sampson
1993-03-13  0:04   ` Michael Feldman
1993-03-16 18:04     ` Tom Pole
1993-03-13  4:15   ` David Weller
1993-03-16 17:58     ` Tom Pole
     [not found] <1no3fbINN3h7@umbc4.umbc.edu*<1993Mar12.232510.7619@seas.gwu.edu>
1993-03-13 22:34 ` news
1993-03-14  0:36   ` Michael Feldman
1993-03-14  8:24     ` Mike Berman
1993-03-14 23:42       ` Michael Shapiro
1993-03-15  3:50         ` Michael Feldman
1993-03-16 21:06           ` fred j mccall 575-3539
1993-03-17  4:12             ` Michael Feldman
1993-03-14 12:51   ` Don Tyzuk
     [not found] <1no3fbINN3h7@umbc4.umbc.edu*<1993Mar12.232510.7619@seas.gwu.edu*<1993Mar14.003649.24085@seas.gwu.edu>
1993-03-14 14:01 ` news
  -- strict thread matches above, loose matches on Subject: below --
1993-03-18  0:41 Robert I. Eachus
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