Group items tagged

The first multi-person non-invasive direct brain-to-brain interface for collaborative problem solving

Graph coloring with an infinite number of vertices requires at least 5 colors (compared to the 4-color-theorem).

The best paper on transformation optics written ever :-)

Concerning the fabrication... as usual, no idea. I agree that this is the main drawback of MM, and certainly difficult to overcome. I would double check that number, because its value is related with the beam shape of Fig. 1 A. I believe that the simulations are correct, it's just a detail.

wow ... still publishing despite babysitting and new job!!

Francesco and Sante s paper is out - let's see the reactions ....

They search numerically for initial conditions resulting in periodic orbits. Reminds to me the methods we employed for the "search for invariant relative motion" and which brought us to discover the magic inclinations (47.9 degrees). I wonder what are the implications. In any case nice plots :)

Haven't read in detail, but it's not clear to me what it means exactly. If they were discovered numerically (I assume it means via numerical integration), how can they be sure the orbits are truly periodic?

looks like some backwind for all the cold fusion believers ...

I just answered something very similar to Franco, except the conclusions: I don't think that there is a good reason for us or anybody else in ESA to get involved at this stage.

I agree - if this device would work it there would be other interest groups (like the energy sector) with a much more concrete stake in the technology.

How many shapes can be obtained by folding a paper and applying just one straight cut? You'll be surprised...

"The theorem is that every pattern (plane graph) of straight-line cuts can be made by folding and one complete straight cut. Thus it is possible to make single polygons (possibly nonconvex), multiple disjoint polygons, nested polygons, adjoining polygons, and even floating line segments and points." - So the you can cut any assembly of polygons but not a single curved edge (with a finite number of folds (points don't count)): useless. :-P

Asimov's Foundation meets ACT's Tipping Point Prediction?

still, some interesting thoughts in there ... "Then you have the 50-year cycles of violence. Turchin describes these as the building up and then the release of pressure. Each time, social inequality creeps up over the decades, then reaches a breaking point. Reforms are made, but over time, those reforms are reversed, leading back to a state of increasing social inequality. The graph above shows how regular these spikes are - though there's one missing in the early 19th century, which Turchin attributes to the relative prosperity that characterized the time. He also notes that the severity of the spikes can vary depending on how governments respond to the problem. Turchin says that the United States was in a pre-revolutionary state in the 1910s, but there was a steep drop-off in violence after the 1920s because of the progressive era. The governing class made decisions to reign in corporations and allowed workers to air grievances. These policies reduced the pressure, he says, and prevented revolution. The United Kingdom was also able to avoid revolution through reforms in the 19th century, according to Turchin. But the most common way for these things to resolve themselves is through violence. Turchin takes pains to emphasize that the cycles are not the result of iron-clad rules of history, but of feedback loops - just like in ecology. "In a predator-prey cycle, such as mice and weasels or hares and lynx, the reason why populations go through periodic booms and busts has nothing to do with any external clocks," he writes. "As mice become abundant, weasels breed like crazy and multiply. Then they eat down most of the mice and starve to death themselves, at which point the few surviving mice begin breeding like crazy and the cycle repeats." There are competing theories as well. A group of researchers at the New England Complex Systems Institute - who practice a discipline called econophysics - have built their own model of political violence and

It's not the scientific activity described in the article that is uninteresting, on the contrary! But the way it is described is just a bad joke. Once again the results itself are seemingly not sexy enough and thus something is sold as the big revolution, though it's just the application of the oldest scientific principles in a slightly different way than used before.

The Robobee takes off without guide wires! It is still powered via a wire, and the control is done with the help of a VICON system and on an external computer, but this still is an amazing feat!

The way they make this thing is just as impressive. The manufacturing technique is "pop-up book" folding, a method that has been developed by the same group and that allows a two dimensional monolithic MEMS structures to be easily assembled into a 3D structure. I actually put this as an item of the "Technology List 2020" on the wiki this morning.

I agree, manufacturing is the amazing thing here ..... as soon as the power-consumption/density problem is solved these things will really take off :)

Nice article on how bumblebees optimize their path from flower to flower.

Oh, I like this one. One more point for swarm intelligence! :)

We could have come up with an inspiration like this !!! As creative as the roots :-) "These male amphibians use their calls to attract the female, who can recognise where it comes from and then locate the suitor. The problem arises when two males are too close to one another and they use their call at the same time. The females become confused and are unable to determine the location of the call. Therefore, the males have had to learn how to 'desynchronise' their calls or, in other words, not call at the same time in order for a distinction to be made."

"Australia's Royal Air Force has been left red-faced after a job ad asked applicants to solve a complex math problem was revealed to be unsolvable. Bosses posted the puzzle in a bid to attract the country's best minds to its ranks"

Meet the incredible shrinking material. Most things swell when they warm up, creating engineering headaches, but now a 3D-printed material has been configured to contract instead. When two interlinked materials expand at different rates, they can warp or crack. It's a problem in buildings, bridges, electronics and anything else that is exposed to a wide temperature swing.

google paper on quantum computers ... anybody with further insight on how realistic this is

Not an answer to Leopold's question but here is a little primer on quantum computers for those that are (like me) still confused about what they actually do: http://www.dwavesys.com/tutorials/background-reading-series/quantum-computing-primer It give a good intuitive idea of the kinds of problems that an adiabatic quantum computer can tackle, an easy analogy of the computation and an explanation of how this get set up in the computer. Also, there is emphasis on how and why quantum computers lend themselves to machine learning (and maybe trajectory optimization??? - ;-) ).

A nice read. IBM Watson wowed the tech industry with a 2011 win against two of television show Jeopardy greatest champions. Using something that seemed like a sort of tree search for me IBM DeepQA algorithm managed to ingest sparse data (clues), process it getting one answer, understand what that answer means and come up with the question that leads to that answer. Now, IBM tells us that the same system can tackle medical diagnosis and financial risk problems.

Interesting. these guys are apparently gonna try developing pulsar navigation. They propose to solve the low apparent brightness problem using relatively complex signal processing and filtering to limit the antenna size etc. The say they've already had some promising results using ground based data. worth a science coffee perhaps?

Absolutely. Sante can you get in contact with them?

A real scientific study...

Computer scientists prove that networks of cells can compute as efficiently as networks of computers linked via the internet