Month: February 2008
-
Danger Theory and artificial immune systems
In recent years, various researchers have attempted to build computer security systems modelled on the human immune system. The idea is that if the system detects an invader, this triggers an immune response that kills the foreigner. These systems don’t work terribly well, perhaps because the human immune system doesn’t work like that either. In…
-
First light from Keck’s null mode
Astronomers from the Keck Observatory at the summit of Mauna Kea in Hawaii are reporting the first results from the telescope used as an interferometer in “null mode”. For background, the Keck Observatory consists of two 10 m telescopes that work together to give combined resolution equivalent to an 85 m mirror. It’s easily the…
-
How cricketers get their eye in
It’s long been known that batsman in the venerable game of cricket are more likely to get out early in their innings, before they “get their eye in”. Various factors seem to be to blame, such as the time it takes for the batsmen’s footwork to warm up and for them to adapt to the…
-
In case ya missed ’em…
This week’s posts from the physics arXiv blog: Extreme ice and the blues How to reduce extremism? Travel! Australians make interstellar hologram Why silos burst Feline ballistics
-
Hair ‘n’ fur
The best of the rest from the physics arXiv this week: Fermi, Pasta, Ulam and a Mysterious Lady Parametric sound generation. Theory and experiments Suprafroth (Superconducting Froth) Suction Effects in Deep Boom Clay Block Samples Asynchronous Remote Medical Consultation for Ghana
-
Feline ballistics
Here’s a straightforward question in ballistics: What velocity do you need to launch a 350 pound object over a 12.5 foot barrier that is 33 feet away? The answer, thanks to Raza Syed, a physicist at Northeastern University in Boston, and a pal is: 26.7 miles per hour at an angle of about 55 degrees.…