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Comment Re:The arguments of olde - don't carry much weight (Score 1) 287

Substitute V = A * R into W = V * A to get equivalently:

W = A^2 * R
or:
W = V / R^2

This is the power lost as heat in the wiring. You can see that losses increase with the square of current, but only linearly with voltage. Its about losses in long wiring runs at 48VDC. Compare typical household 10A at 240VAC with 50A at 48VDC for 1km of wiring in a data centre. 10A requires 14AWG wiring which is 8.450 ohm/km with conductor area of 2.08mm2. 50A requires 6AWG wire which is 1.320 ohm/km with conductor area of 13.30mm2.

10A Wiring Power Loss = 10^2 * 8.45 = 845W
50A Wiring Power Loss = 50^2 * 1.32 = 3300W
Ratio 3300/845 = 3.9

However, economic cost of install also needs to be considered. Ratio of conductor area:
13.3 / 2.08 = 6.4 times copper for 48VDC system, hence 6.4 times more expensive in materials to install.
Add to this the significant additional labour labour of working with larger, heavier and stiffer cable.

Comment Re:Riot (Score 1) 589

Thats not insightful - its completely wrong about human nature. Not getting a converter box NOW doesn't hurt them NOW - ergo the lazy don't notice / don't care. Its human nature to put up with things until a breaking point is reached and then they go berserk. They will only react once their RIGHT to TV is taken away.

GP is correct - but how serious and how long it lasts remains to be seen.

Announcements

Submission + - 'Lifesaver bottle' filters out viruses (telegraph.co.uk)

gihan_ripper writes: "British inventor Michael Pritchard has developed a small self-contained filter system that instantly cleans water, removing all particles larger than 15nm. Speaking to the Telegraph, he said that he was inspired after seeing the effects of Hurricane Katrina and the Boxing Day tsunami in 2004; people had to wait for many days to get fresh water and many died from drinking contaminated water. The filter is so effective that it can purify dirty river water and even faecal matter. His bottle will shortly be available for sale from Lifesaver Systems at an expected cost of £190 (approx. $385)."
Debian

Submission + - Debian win32-loader goes official (goodbye-microsoft.com)

An anonymous reader writes: After a long process of review and polishing, the win32 loader from http://goodbye-microsoft.com has finally made its way to official Debian CDs. Latest daily builds of lenny (the development version) are including it, making the start of Debian Installer as simple as just a few clicks. The win32-loader version, now based on GRUB 2, includes new features such as detection and preseeding of Windows settings, and is translated to 20 languages.
Upgrades

Submission + - ESR had enough with Fedora, moved to Ubuntu

sufehmi writes: "After almost losing his data because of a minor update from Fedora, ESR finally call it quits. In his posting on fedora-devel@, he lambasted on the purist attitude of the Fedora project, while losing touch with the reality.

I've moved away from Fedora once I realized that security updates are not going very well for older versions, endangering my computers; especially after the Fedora legacy project folded up.

Personally, I think it's possible to find a middle-path; where a Linux distro is both free (as in freedom) and Just Works (tm) for your average John Doe."

Feed High-Def DVD Crackers Lie Low (wired.com)

A company that sells ripping software for high-definition disks operates through a corporate maze reaching from Ireland to Antigua. Good luck, MPAA. In 27B Stroke 6.


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