Re: OT?: AF 447 and avionics software

[MRE <Marc.Enzmann@web.de>]

On 7 Jun., 15:19, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> On Sun, 07 Jun 2009 13:16:14 +0200, Florian Weimer wrote:
> > * Dmitry A. Kazakov:
>
> >> Analogue systems are continuous, whatever complexity a continuous
> >> system has it stay to some extent predictable.
>
> > Even if you've got resonance effects?
>
> Yes. An oscillation does it with finite mass and energy The acceleration is
> limited, which is another way to say that it is continuous.
>
> In a discrete computing system a huge number of states are "equidistant".
> You pay the same "price" for incrementing a register by one and for
> resetting the CPU. This allows you to make great things - you can "travel"
> to anywhere you want in very few steps - but this also makes the trajectory
> so unpredictable.
>
> --
> Regards,
> Dmitry A. Kazakovhttp://www.dmitry-kazakov.de

For a single system Dimitry may be right. If however we talk about a
network of
analog systems (which we have in flight controls), the result of a
malfunction
is as unpredictable as for a similar digital system. Thanks to chaos-
theory ;-)

Cheers,

Marc