Friday, January 16, 2009

Interesting reads for the weekend

1. 30th Anniversary of the Spreadsheet (Very interesting and sarcastic perspective on how the spreadsheet has shaped our society)

2009 marks the 30-year anniversary of the now-ubiquitous spreadsheet program. And society as a whole has deteriorated ever since its invention. It was the spreadsheet that triggered the PC revolution, with VisiCalc the original culprit. Can anyone say that we've actually benefited from its invention? Look around: I think we've suffered.


2. How undersea cables get repaired

Videos of how the repair process works.

[Update] This Alcatel page explains the process with text and a cool flash animation. It also has a section on how cables are laid in the first place.

3. Interview with an adware author

Very interesting business and technical insights into the dark part of the cyber-world.

4. 10-power saving myths debunked


5. Saving power in datacenters with DC power

Interesting article on how converting from AC to DC in datacenters may help save power.


In a typical datacenter environment, power conversions abound along the path from the outside utility pad to the servers. With each conversion, some power is lost. The power starts at the utility pad at 16,000 VAC (volts alternating current), then converted to 440 VAC, to 220 VAC, then to 110 VAC before it reaches the UPSes feeding each server rack. Each UPS converts the incoming AC power to DC power, then back to AC. The UPSes then distribute that AC power to their respective servers -- where it's converted back to DC. As much as 50 to 70 percent of the electricity that comes into the datacenter is wasted throughout this long and winding conversion process.

There's a more efficient approach, one promoted by Validus DC Systems: taking the utility-supplied 13,000 VAC and converting it directly to 575 VDC (volts direct current) using an outdoor-rated conversion unit, then running power into the datacenter over 1.5-inch cabling. Each rack in the datacenter then has a 575-to-48-VDC converter that is 95 percent efficient. The direct DC approach can save users 50 percent or more between cooling savings and elimination of conversion losses, according to Ron Croce, COO of Validus

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