Received: by alpheratz.cpm.aca.mmu.ac.uk id TAA06874 (8.6.9/5.3[ref pg@gmsl.co.uk] for cpm.aca.mmu.ac.uk from fmb-majordomo@mmu.ac.uk); Wed, 27 Sep 2000 19:32:55 +0100 Subject: Fwd: Computer Used To Study Crowd Panic Date: Wed, 27 Sep 2000 14:29:42 -0400 x-sender: wsmith1@camail2.harvard.edu x-mailer: Claris Emailer 2.0v3, Claritas est veritas From: "Wade T.Smith" <wade_smith@harvard.edu> To: "memetics list" <memetics@mmu.ac.uk> Content-Type: text/plain; charset="US-ASCII" Message-ID: <20000927182941.AAA28737@camailp.harvard.edu@[128.103.125.215]> Sender: fmb-majordomo@mmu.ac.uk Precedence: bulk Reply-To: memetics@mmu.ac.uk
---------------- Begin Forwarded Message ----------------
News Article: Computer Used To Study Crowd Panic
By MATTHEW FORDAHL, AP Science Writer
Mob stampedes have killed thousands of people in recent years,
but they are usually explained in terms of psychology. Now,
European scientists say they can predict and prevent crowd panic
via computer simulations using the laws of physics.
The new computer model relies on distances, sizes and velocities
instead of emotional states but produces results similar to actual
panics, the researchers said in Thursday's issue of the journal
Nature.
"We think it works particularly well in panic situations
because people don't think about what they should do," said Dirk
Helbing, a professor at the Institute for Economics and Traffic at
Dresden University of Technology.
The computer models reflect the conditions of a room from which
people are trying to escape but cannot use or see exits. The
virtual victims appear as particles that reflect an average
person's speed, size and desired distance from others.
Under normal circumstances, a crowd exits a theater or stadium
in an orderly and coordinated fashion because everyone is moving at
a leisurely pace and at an adequate distance from one another, the
researchers said.
But when the speed of the individuals increases in a panic, they
bump into each other, creating friction and violating personal
space. As a result, almost everybody moves less quickly.
Eventually, solid arch-shaped barriers of people clump around
the exits and even fewer people can pass to safety. Victims
collapse and are trampled, creating further obstacles for the
others.
"People want to leave faster, but the result is that they are
leaving slower and then the tragedy begins," Helbing said. "The
question is what can you do about that?"
One solution is to build a partial barrier in front of the exit,
the researchers said. It could absorb pressure from the crowd that
can become strong enough to crush a person, break a brick wall or
bend steel.
"It turned out that we had no injuries," Helbing said of the
approach.
As the world becomes more crowded, such simulations will grow
more important for architects, event planners and police.
This year, eight people were killed in July at a rock festival
in Copenhagen, and a dozen died the same month after a World Cup
match in Zimbabwe. Ten years ago, more than 1,400 pilgrims were
killed inside a tunnel leading to Mecca.
Helbing and colleagues Illes Farkas and Tamas Vicsek found many
causes for panic. In some cases, a crisis like a fire or a poorly
planned obstacle can drive the hysteria.
The researchers also used their simulation to devise strategies
for surviving crowd panic. In the case of a burning theater where
smoke obscures the exits, just acting alone or totally following
others can be deadly, they said. The solution is to do a little of
both.
"It requires some individualism to explore the environment, to
find the possible solutions and then, if there is someone who found
the solution, it is good for the others to follow," Helbing said.
The new computer models are especially useful because they
consider individual actions within the group, David J. Low, a civil
engineer at Heriot-Watt University in Scotland, said in an
accompanying commentary.
Most modern buildings are designed assuming crowds flow through
the exits like fluid through a pipe, he said.
"This traditional approach assumes that the crowd is made up of
identical, unthinking elements," he said. "A fluid particle
cannot experience fear or pain, cannot have a preferred motion,
cannot make decisions and cannot stumble and fall."
---
On the Net: Nature magazine: <A
HREF=http://www.nature.com>http://www.nature.com>
----------------- End Forwarded Message -----------------
===============================================================
This was distributed via the memetics list associated with the
Journal of Memetics - Evolutionary Models of Information Transmission
For information about the journal and the list (e.g. unsubscribing)
see: http://www.cpm.mmu.ac.uk/jom-emit
This archive was generated by hypermail 2b29 : Wed Sep 27 2000 - 19:34:29 BST