## Wednesday, December 31, 2003

The 5 Ghz liquid nitrogen cooled chip

Here is a CPU Cooling With Liquid Nitrogen Record Attempt: The 5 GHz Project. An interesting data is the extreme heat dissipation that needs to accomodate for the 1600 KW per square meter, or about a thousand times the heat flux received from the sun on a solar panel in space. Liquid nitrogen only helps because the actual surface area in this example is small. The actual output is 84 W (not much more than a light bulb). A capillary loop heat pipe would do the job without having to resort to cryogenics. But hey, liquid nitrogen looks good on slashdot.
A more focused search engine

Here is a search engine that seem to significantly do better than google on very narrowly focused search (especially in science and especially for france): Reacteur.com. With this one I found this document (from here and here). Something I could not find easily with google. I understand the subject is very narrow, but sometimes this type of search is very much needed. Then again in order to further the initial search I had to go back to google to find this site.

## Friday, December 26, 2003

Racing for a million buckarus...

When DARPA came up with the concept of offering a million bucks for a their grand challenge, little did they realize people would come in droves. They were expecting about 25 teams with really about 4 or 5 strong contenders. The deadline for regsitration passed and they had 120 teams listed as potential competitors. They had to go through a process by which to weed out some of the teams. And they did. They now have about 25 teams. The 25 teams that are currently accepted in, have to go through DARPA's inspection and then have to show up in March in California. The people who did not get accepted felt it was somehow unfair, so they decided to set up their own challenge. One rule: come with your vehicle on day one and race. No inspection, just show up. My team did not get selected, however, I am thinking about having a stronger team next year for either the official DARPA or the IRRF challenges. For those who don't know about it. The rule is simple, build an autonomous vehicle that can drive 300 miles in 10 hours.

## Monday, December 22, 2003

### Using a Programming Language for your Graphics Card

This Brook Language is interesting. Now one can think of the graphics card as a CPU. Some of the numbers I have seen seem to be in line with some of the FGPA speed I had looked into earlier. Maybe a real use of this type of Hardware is to go after the first prime with 10^6 digits. Or maybe, stream processing is the only way to solve the linear transport equation. A good review of what it or cannot do can be found here. Looks like it is ideally suited for a Monte_carlo type of computation. We did a small study on a shading type of algorithm with an 2 million gates FPGA and the thing was beating a pentium 2 GHz machine a hundredfold. The interesting information was that the FPGA was only running at about 100 MHz. A 2 Ghz general CPU is beaten on a specific purpose computation a hundredfold with a chip clocked at 1/20th the rate.

## Friday, December 19, 2003

Desperately Seeking Primes