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Transportation

Submission + - A $20 Cardboard Bicycle Could Revolutionize World's Transportation 1

Hugh Pickens writes writes: "Reuters reports that a bicycle made almost entirely of cardboard designed to be manufactured at about $9 to $12 per unit that would be sold for about $20 has the potential to change transportation habits from the world's most congested cities to the poorest reaches of Africa. "In six months we will have completed planning the first production lines for an urban bike which will be assisted by an electric motor, a youth bike which will be a 2/3 size model for children in Africa, a balance bike for youngsters learning to ride, and a wheelchair that a non-profit organization wants to build with our technology for Africa," says Nimrod Elmish. The bicycles are not only very cheap to make, but at 20 pounds they are very light and do not need to be adjusted or repaired, the solid tires that are made of reconstituted rubber from old car tires will never get a puncture. "These bikes need no maintenance and no adjustment, a car timing belt is used instead of a chain, and the tires do not need inflating and can last for 10 years," says Elmish adding that the bicycles will be so cheap, it hardly matters how long they last. "So you buy one, use it for a year and then you can buy another one, and if it breaks, you can take it back to the factory and recycle it." Cardboard, made of wood pulp, was invented in the 19th century as sturdy packaging for carrying other more valuable objects, it has rarely been considered as raw material for things usually made of much stronger materials, such as metal. Inventor Izhar Gafni spent years figuring out how to make cardboard strong enough to support a human. The trick was bending and gluing the cardboard in such a way that it becomes strong like a piece of wood. In a video, Gafni describes the process as a type of origami, and demonstrates how his cardboard is strong enough to support a car. As in crafting origami and tearing telephone books, Gafni explains, “[if] you fold it once, and it’s not just twice the strength, it’s three times the strength.”"
Google

Submission + - How Google Cools its 1 Million Servers (datacenterknowledge.com)

1sockchuck writes: As Google showed the world its data centers this week, it disclosed one of its best-kept secrets: how it cools its custom servers in high-density racks. All the magic happens in enclosed hot aisles, including supercomputer-style steel tubing that transports water — sometimes within inches of the servers. How many of those servers are there? Google has deployed at least 1 million servers, according to Wired, which got a look inside the company's North Carolina data center. The disclosures accompany a gallery of striking photos by architecture photographer Connie Zhou, who discusses the experience and her approach to the unique assignment.

Comment Re:Environmentalists (Score 1) 319

Okay, firstly; your math is out - a far smaller number of people would have to walk into gas chambers on a daily basis to reduce our population to your arbitrary target well within 20 years. Currently significant population factors (birth rate and death rate) are compounded as a ratio (i.e. about 20 per 1,000) onto the existing population; any fixed-amount reduction that outweighs the initial difference in geometric components for population increase and decrease will become the dominant factor very quickly.
365 million out of (I'm assuming your starting number was 20 * 365.25m + 200m = ) 7.5 billion isn't much of a decrease in the first year (a little under 5%) but I'm sure you can see from here the compounding nature of the figure; once you're down to 500 million, another year would take over half your population.

Perhaps more egregiously, are you saying that a significant amount of our environmental impact as a species is our own poop?

Comment Re:gnupg it (Score 1) 402

Or print the key (ideally not passphrase-protected, or with a memorable password given to your executor) in ASCII and attach it to your lawyer's copy of your will. Use an OCR-friendly font, maybe throw in a copy on a USB drive. Once you've backed-up the private key and made sure it's accessible without your intervention, you won't need it so delete it. Save a list of up-to-date passwords (or perhaps your keychain and it's password; which could be more automated) encrypted with the public key somewhere easily accessible (web storage? Google Docs?)

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