When spacecraft return to Earth, one of the tensest parts of the mission is the radio black out that occurs as the vehicle re-enters the atmosphere. Travelling at hypersonic speeds of between Mach 8 and 15, the spacecraft heats and breaks down molecules in the atmosphere causing a plasma to form. It is this plasma sheath that prevents radio communication.
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Could Tiny Bubbles Cool the Planet? - 1 views
Waking up the quantum vacuum - 1 views
Obama Orders Review of Synthetic Biology - ScienceInsider - 1 views
Slashdot Games Story | Google PAC-MAN Cost 4.8M Person-Hours - 3 views
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stupid calculation
Russian Physicists Solve Radio Black-Out Problem for Re-Entering Spacecraft ... - 1 views
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Ref: arxiv.org/abs/0704.3103: Communication Through Plasma Sheaths
Generation of light bullets - 1 views
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We have the bullets, so when we'll have the gun?
The Fantastical Promise of Reversible Computing - Technology Review - 2 views
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Reversible logic could cut the energy wasted by computers to zero. But significant challenges lie ahead.
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By some estimates the difference between the amount of energy required to carry out a computation and the amount that today's computers actually use, is some eight orders of magnitude. Clearly, there is room for improvement.
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There are one or two caveats, of course. The first is that nobody has succeeded in building a properly reversible logic gate so this work is entirely theoretical. But there are a number of computing schemes that have the potential to work like this. Thapliyal and Ranganathan point in particular to the emerging technology of quantum cellular automata and show how their approach might be applied.
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We did look at making computation powers more efficient from the bio perspective (efficiency of computations in brain). This paper was actually the base for our discussion on a new approsach to computing http://atlas.estec.esa.int/ACTwiki/images/6/68/Sarpeshkar.pdf and led to several ACT internal studies -
here is the paper I told you about, on the computational power of analog computing: http://dx.doi.org/10.1016/0304-3975(95)00248-0 you can also get it here: http://www.santafe.edu/media/workingpapers/95-09-079.pdf
Infertility Could Impede Human Space Colonization - Slashdot - 0 views
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For Giusy...
Why Randomly-Selected Politicians Would Improve Democracy - Technology Review - 4 views
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If Pluchino sounds familiar, it's because we've talked about him and his pals before in relation to the Peter Principle that incompetence always spreads through big organisations. Back in 2009, he and his buddies created a model that showed how promoting people at random always improves the efficiency of the organisation. These guys went on to win a well-deserved IgNobel prize for this work.
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Ref: arxiv.org/abs/1103.1224: Accidental Politicians: How Randomly Selected Legislators Can Improve Parliament Efficiency
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I think I start to understand why Italian politics does so horribly bad... -
... because they don't follow this rule!
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According to the authors we have four types of people in the parlement: 1) intelligent people whose actions produce a gain for both themselves and for other people. 2) helpless/naive people in the top left quadrant whose actions produce a loss for themselves but a gain for others; 3) bandits whose actions produce a gain for themselves but a loss for other people. 4) stupid people in the bottom left quadrant produce a loss for themselves and also for other people. According to the above definition it is clear that their model does not apply to the italian parlament where we only have stupid people and bandits.
The nuclear option - 3 views
Tree identification a snap with mobile app - Technology & Science - CBC News - 1 views
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One more nice citizen scientist example as I try to find for space since some time. Any good ideas this mit inspire you to?
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why don't you programme one and get rich?
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Would love to but this requires *TIME* :-( Automatic image-based mushroom recognition... perhaps could do as a FP7 study... it may save lives actually!
Europe's Plan to Move An Asteroid - Technology Review - 3 views
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In 2002, the European Space Agency began a program called Don Quijote to find out how best to perform such a deflection.
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Now, Stephen Wolters at the Open University in the UK and a few friends have published a new analysis of the mission saying that measuring the change in orbit is not enough. Instead, the spacecraft needs to characterise the impact in detail, determining the density of the material near the asteroid's surface, the size of the surface grains as well as the mass and speed distribution of the impact ejecta.
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Ref: arxiv.org/abs/1107.4229: Measurement Requirements For A Near-Earth Asteroid Impact Mitigation Demonstration Mission
Designer lattices - 5 views
Live Chat: Have Neutrinos Broken the Speed Limit of Light? - ScienceNOW - 1 views
Slashdot Technology Story | Is Cloud Computing the Hotel California of Tech? - 2 views
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the cloud is still largely a one-way road into Web services, with closed data networks making it difficult to impossible to move data into competing services
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also interesting is this article quote: "How big can the cloud get before it starts to rain?" http://hardware.slashdot.org/story/09/09/30/0152200/Amazons-Cloud-May-Provision-50000-VMs-a-Day
Rocket company tests world's most powerful ion engine - space - 05 October 2009 - New S... - 2 views
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On Wednesday, it ran its VX-200 engine at 201 kilowatts in a vacuum chamber in Houston, passing the 200-kilowatt mark for the first time.
Researchers Use Radio Waves to "See" Through Walls -- Berardelli 2009 (1015): 2 -- Scie... - 0 views
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Researchers have discovered that an array of radio transceivers--devices that send and receive signals--can track people's movements behind walls. Possible uses include detecting people trapped in burning buildings, controlling lighting or heating and cooling systems as people enter or exit rooms, and spotting burglars or enemy soldiers.
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