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Submission + - Graphene is back. Is the Space Elevator back as well? (

PanHandleDan writes: Graphene is a one-atom-thick sheet of carbon — basically a carbon nanotube in sheet form. In addition to having extraordinary conducting properties, it has a tensile strength of 130GPa, or 200 times that of steel. Until recently, attempts to create graphene in any appreciable size resulted in much weaker material. However, engineers at Columbia University seemed to have made a research breakthrough:

"The Columbia Engineering team wanted to discover what was making CVD [chemical vapor deposition] graphene so weak. In studying the processing techniques used to create their samples for testing, they found that the chemical most commonly used to remove the copper substrate also causes damage to the graphene, severely degrading its strength. Their experiments demonstrated that CVD graphene with large grains is exactly as strong as exfoliated graphene, showing that its crystal lattice is just as perfect. And, more surprisingly, their experiments also showed that CVD graphene with small grains, even when tested right at a grain boundary, is about 90% as strong as the ideal crystal."

What does this mean for the future of not just foldable displays and super long bridges, but of space tourism?


The Tuesday Birthday Problem 981

An anonymous reader sends in a mathematical puzzle introduced at the recent Gathering 4 Gardner, a convention of mathematicians, magicians, and puzzle enthusiasts held biannually in Atlanta. The Tuesday Birthday Problem is simply stated, but tends to mislead both intuitive and mathematically informed guesses. "I have two children, one of whom is a boy born on a Tuesday. What's the probability that my other child is a boy?" The submitter adds, "Believe it or not, the Tuesday thing is relevant. Well, sort of. It's ambiguous."

Tracking Browsers Without Cookies Or IP Addresses? 265

Peter Eckersley writes "The EFF has launched a research project called Panopticlick, to determine whether seemingly innocuous browser configuration information (like User Agent strings, plugin versions and fonts) may create unique fingerprints that allow web users to be tracked, even if they limit or delete cookies. Preliminary results indicate that the User Agent string alone has 10.5 bits of entropy, which means that for a typical Internet user, only one in about 1,500 (2 ^ 10.5) others will share their User Agent string. If you visit Panopticlick, you can get a reading of how rare or unique your browser configuration is, as well as helping EFF to collect better data about this problem and how best to defend against it." I remember laughing years ago when I would see users who had modified their user agent string with some sort of defiant pro-privacy message, without realizing that their action made them uniquely identifiable out of hundreds of thousands of others.

"Universal Jigsaw Puzzle" Hits Stores In Japan 241

Riktov writes "I came across this at a Tokyo toy store last week, and it's one of the coolest things I've seen in a long time. Jigazo Puzzle is a jigsaw puzzle, but you can make anything with it. It has just 300 pieces which are all just varying shades of a single color, though a few have gradations across the piece; i.e., each piece is a generic pixel. Out of the box, you can make Mona Lisa, JFK, etc, arranging it according to symbols printed on the reverse side. But here's the amazing thing: take a photo (for example, of yourself) with a cell-phone, e-mail it to the company, and they will send you back a pattern that will recreate that photo. This article is in Japanese, but as they say, a few pictures are worth a million words. And 300 pixels are worth an infinite number of pictures."

Comment Re:Almost competing (Score 4, Insightful) 706

Upgrading Windows is just asking for trouble.

The OS on my MBP, 10.6 is upgraded from 10.5 which was transferred over from an installation on a different notebook, which was upgraded from 10.4, which was cloned over from yet another notebook, which was upgraded from 10.3. I think that was the last clean install, although it could have actually been 10.2. So this OS has been upgraded through at least four major versions, run on three different machines, with two different major processor architectures (PowerPC and x86).

And it works just fine. I'm sure there are people running Linux with even more impressive provenances.


Packs of Robots Will Hunt Down Uncooperative Humans 395

Ostracus writes "The latest request from the Pentagon jars the senses. At least, it did mine. They are looking for contractors to 'develop a software/hardware suite that would enable a multi-robot team, together with a human operator, to search for and detect a non-cooperative human subject. The main research task will involve determining the movements of the robot team through the environment to maximize the opportunity to find the subject ... Typical robots for this type of activity are expected to weigh less than 100 Kg and the team would have three to five robots.'" To be fair, they plan to use the Multi-Robot Pursuit System for less nefarious-sounding purposes as well. They note that the robots would "have potential commercialization within search and rescue, fire fighting, reconnaissance, and automated biological, chemical and radiation sensing with mobile platforms."

The clothes have no emperor. -- C.A.R. Hoare, commenting on ADA.