indeed, yes, there is such a connection...
The "shockwave traffic jam":
"The mathematical theory behind these so-called "shockwave" jams was developed
more than 15 years ago using models that show jams appear from nowhere on roads
carrying their maximum capacity of free-flowing traffic - typically triggered by
a single driver slowing down.
After that first vehicle brakes, the driver behind must also slow, and a
shockwave jam of bunching cars appears, travelling backwards through the traffic."
Here is a link to an article "Traffic jams without bottlenecks—experimental
evidence for the physical mechanism of the formation of a jam" in the "New
Jornal of Physics":
http://www.iop.org/EJ/abstract/1367-2630/10/3/033001/
and a report with video in New Scientist:
http://www.newscientist.com/article/dn13402
Best regards,
Gustavo
Mensaje citado por: "Filippo A. Salustri" <[log in to unmask]>:
> I'd say there definitely is such a connection. The "damping" and
> "spring"
> constants for cars in traffic are - well, not constant. But constant
> enough
> to make the same effect appear.
> Cheers.
> Fil
>
> 2009/11/20 Birkin, Guy <[log in to unmask]>
>
> > Dear Keith and others,
> >
> > I wonder if there if a similarity here between the propagation of the
> > 'auditory ripples' and the occurrence of spontaneous traffic jams on
> > motorways...?
> >
> > Cars travelling on a motorway are analogous to the train carriages;
> the
> > delay in acceleration between carriages is like the delay between a
> car
> > in front braking and the time when you apply your car's brakes to
> avoid
> > hitting it. The cars are moving forwards but the 'braking wave' is
> > propagated backwards. It seems to me that if the speed of propagation
> of
> > the 'braking wave' exceeds the speed of the cars, then a jam can
> result.
> >
> > I'm sure I've seen reports on this somewhere, but it's not my area so
> I
> > don't have a reference to hand.
> >
> > Regards,
> >
> > Guy
> >
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>
> --
> Filippo A. Salustri, Ph.D., P.Eng.
> Mechanical and Industrial Engineering
> Ryerson University
> 350 Victoria St, Toronto, ON
> M5B 2K3, Canada
> Tel: 416/979-5000 ext 7749
> Fax: 416/979-5265
> Email: [log in to unmask]
> http://deseng.ryerson.ca/~fil/
>
MDI Gustavo Victor Casillas Lavin
Centro de Investigaciones de Diseño Industrial
UNAM
(5255) 5622 0835
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