Cosmic Rays and SolidWorks

Ran across an article in the latest EDN (May 12th, 2005) regarding the
effect of Cosmic Rays on computer reliability. The problem is called
SEE (Single Event Effects). Imagine your system as being a large Geiger
counter in which a particle like a neutron matter interaction can
temporarily cause a part of a memory or CPU to be in a state other than
that caused by the program it is running.

SEEs, suh as soft errors, have since the early 1980s appeared in
commercial electronics, but they are now becoming the dominant
reliability-failure mechanism in modern CMOS technologies.

It goes on to say that Sun recalled some workstations in the late '90s
due to this problem.

On page 50 Table A shows the susceptibility of various chip
technologies to SEEs. At 90nm and below SEEs are a problem for both
memory and logic circuits.

We have often noted that SW has become more and more prone to random
CTDT type problems since SW2000. This parallels the widespread use of
130nm and smaller chip technologies. With all the other possible causes
of SW crashing this is one of the more bizarre things that will appear
on my list.

Apparently it is possible to take steps to minimize the effect of SEEs.
ECC memory is a start. There are apparently programming steps that can
help also. Encasing a system in a couple inches of lead might also
help.

 

This has all been well known for over 50 years.

 

I think the thing that was no known 50 years ago was how small we
were going to be making thing. I imagine that a regular size
transistor is not vulnerable to this at all.

 

this had me wondering - could SEE's theoretically affect the human
brain ? it sounds like it depends partially on the size of the
neurons. from a quick websearch it sounds like a "typical" neuron is
10 microns, 1000 nanometers (i might be getting my latin pico and nano
mixed up)

http://www.enchantedlearning.com/subjects/anatomy/brain/Neuron.shtml

"There are many type of neurons. They vary in size from 4 microns (.004
mm) to 100 microns (.1 mm) in diameter."

PHEW ! i guess we're safe.

remember the "twinkies defense", when dan white killed SF mayor moscone
& then pleaded low blood sugar or something ? i was wondering if this
info about SEE's had any legal implications.

sorry, couldn't resist. blame the coffee.

 

http://www.phys.ualberta.ca/~gingrich/atlas/radiation/SEEnotes.html

There are reasons that transistors were not used in nuclear
reactors and that even critical transistor-based devices sometimes
came in radiation-hardened varieties.

It's long been an issue for the military and satellites as
well.

IIRC Silicon-based devices differ from Germanium ones
as well (Solid State Physics was long ago, sadly <g>.)

 

SEE's most likely would not effect the brain because information in the
brain is stored within in a error correcting intercellular matrix. And
I'm not talking about the movie

 

Wereas SolidWorks code has a lot of single point failure modes. I have
looked at a lot of log files from a lot of different users and seen a
lot of seemingly random memory errors. I guess there is a reason why
the space shuttle uses triple redundant computers.

With SW, Inc. collecting all that log file information by email they
might just have one of the broadest aperture cosmic ray detectors on
earth and not realize it.

 

When I lived In South Africa during the Angolan war, the South Africans
downed a Russian Mig in Angola, it was one never seen in the West before.
The CIA sent in a team with the South Africans to retrieve the aircraft for
further investigation. When the aircraft was retrieved the CIA laughed when
they found avionic components were still using valves (the US calls them
something else). They soon changed their tune when the South Africans
pointed out that the Mig could survive a nuclear fallout and stay in
operation when in fact the US planes would fall out of the sky.

 

Vacuum tubes.

 

I think the term is "vacuum tube", and it's true that they are
relatively unaffected by electromagnetic pulse (EMP). Not that
necessarily the circuits that they are in wouldn't be vulnerable.
Anything more than a very short circuit trace itself picks up
considerable voltage from EMP. Many thousands of volts are quite
possible to be inducted by a relatively short length of unshielded
cable. Modern US military aircraft, however, are designed with all that
in mind. As a beginning (and only to begin with), electronics boxes are
all grounded to the airframe and all cables are shielded.

 

Another way to see it is being able to withstand the effect of EMP from the
other side.
There are also non nuclear weapons designed to send EMP that are powerfull
enough to affect men.

 

Hi Spork,
nearly all modern aircraft in the last 20 years have had that, to protect
from HIRF (high intensity radio frequencies). This actually stems from a guy
driving his Merceded around the Alps, his ABS system locked up due to HIRF
interference and killed him.

 

Not surprised, and glad to know it. I was aware only of the military
avionics end having working in the defense electronics industry, but it
stands to reason that the FAA has demanded it (in the very least) for
commercial passenger aircraft if not all aircraft.

'Sporky'

 

They can all be struck by lightening. Makes a fine EMP pulse.

 

That's why they don't want you to use radio transmitters on aircraft.
They still aren't 100% sure they are fully protected.

BTW, have you ever noticed that a cell phone receiving a call while
next to a mouse or Spaceball can throw your computer into a tizzy?