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Thijs Versloot

This "Space Glass" Lets You Drink Whiskey In Orbit - 3 views

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    Photo credit: The glass has a number of interesting innovations. Ballentine's. A liquor company has created a " Space Glass" that they say can work in the microgravity environment of space. The Open Space Agency's James Parr was commissioned to create the product, and the results are actually quite interesting.
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    Makes sense specially after seeing very good japanese whiskey arriving at the ISS :-) http://phys.org/news/2015-08-japanese-whisky-international-space-station.html
Alexander Wittig

Attack on the pentagon results in discovery of new mathematical tile - 2 views

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    In the world of mathematical tiling, news doesn't come bigger than this. In the world of bathroom tiling - I bet they're interested too. If you can cover a flat surface using only identical copies of the same shape leaving neither gaps nor overlaps, then that shape is said to tile the plane. Also only mathematicians can put the words "Pentagon", "attack", and "plane" in the same sentence...
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    I especially love this part of the story: "The hunt to find and classify the pentagons that can tile the plane has been a century-long mathematical quest, begun by the German mathematician Karl Reinhardt, who in 1918 discovered five types of pentagon that do tile the plane. (To clarify, he did not find five single pentagons. He discovered five classes of pentagon that can each be described by an equation. For the curious, the equations are here. And for further clarification, we are talking about convex pentagons, which are most people's understanding of a pentagon in that every corner sticks out.) Most people assumed Reinhardt had the complete list until half a century later in 1968 when R. B. Kershner found three more. Richard James brought the number of types of pentagonal tile up to nine in 1975. That same year an unlikely mathematical pioneer entered the fray: Marjorie Rice, a San Diego housewife in her 50s, who had read about James' discovery in Scientific American. An amateur mathematician, Rice developed her own notation and method and over the next few years discovered another four types of pentagon that tile the plane. In 1985 Rolf Stein found a fourteenth. Way to go!"
Ma Ru

Command line tools for the Google Data APIs - 2 views

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    I'm sure Francesco will love it... perhaps of use for ACT's Google calendar/docs?
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    is there an easy way (easy for Francesco I mean) to retrieve the citation number of papers in google scholar automatically (e.g. for act papers)?
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    It seems like google scholar is not supported yet.
Francesco Biscani

Saturn's rings gave birth to mini-moons - 0 views

  • Low density, recent surfaces, and somewhat oblong shapes all hint that some of these moons are likely to be less than 100 million years old.
  • Researchers suspected that the moons might have originated through some sort of interactions within the A Ring, but the number of bodies involved made modeling the system too computationally challenging. Fortunately, Moore's Law caught up with Cassini, and today's issue of Nature contains a paper that describes a model that successfully reproduces the pattern of moons we now observe.
pacome delva

An evil atmosphere is forming around geoengineering - 0 views

  • A number of right-wing think tanks actively denying climate change are also promoting geoengineering, an irony that seems to escape them.
  • Wood believes that climate engineering is inevitable. In a statement that could serve as Earth's epitaph, he declared: "We've engineered every other environment we live in, why not the planet?"
  • It's estimated that if whoever controls the scheme decided to stop, the greenhouse gases that would have built up could cause warming to rebound at a rate 10 to 20 times that of the recent past - a phenomenon referred to, apparently without irony, as the "termination problem".
duncan barker

Challenging Existence of 'Absolute Time' - 3 views

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    I doubt that Shnoll is really the first one making such experiments, but perhaps they are more complete than any others done before. Similar things are very popular in the context of Psychology and more exotic fields. If I remember correctly someone ran long experiments with random number generators... Mostly the stories died after a short time, since the experiments are not reproducable. Anyway, why do these guys always have to claim that their work is somehow fundamentally changing our view of physics, notoriously referring to Einstein-Bohr debates and this stuff. That's nonsense! If these effects exist the first explanation is always much simpler. There is somewhere something that influences physics on Earth in a defined way. But this influence depends on the relative position or whatever of the Earth to that whatever-it-is. No problem with absolute time and all that sh...
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    Two years ago, nearly unnoticed in the West, the Russian biophysicist S.E. Shnoll published a paper in the prominent Russian physics journal Uspekhi Fisicheskikh Nauk ..... ah then ...
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    You are right, Leo, they are mostly Russians that publish in some unspellable Journals nobody knows.... or then they are supported by Templeton Foundation.
Joris _

Obama's dream of Mars at risk from radiation - physicsworld.com - 0 views

  • Schwabe cycle
  • Schwabe cycle, where sunspot numbers reach a peak roughly once every 11 years
  • the intensity of each solar maximum is also thought to oscillate over a period, called the Gleissberg cycle
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  • The worse-case scenario is that if you radiate a crew sufficiently, they'd all succumb to radiation sickness within a few days and essentially vomit and diarrhoea themselves to death within an enclosed capsule
  • The Moon missions were just blind lucky,” explains Lewis Dartnell, an astrobiologist at University College, London. “The astronauts would have experienced radiation sickness and a higher risk of future cancer if they'd been hit,” he adds.
  • Hapgood and colleagues are currently working on an alternative technique that involves surrounding the spacecraft with a plasma shield to deflect incoming protons without creating secondary radiation
pacome delva

Can Google Predict the Stock Market? - ScienceNOW - 2 views

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    in related news: Twitter Mood Predicts The Stock Market "An analysis of almost 10 million tweets from 2008 shows how they can be used to predict stock market movements up to 6 days in advance" http://www.technologyreview.com/blog/arxiv/25900/ http://arxiv.org/abs/1010.3003
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    not overly impressive: "The Google data could not predict the weekly fluctuations in stock prices. However, the team found a strong correlation between Internet searches for a company's name and its trade volume, the total number of times the stock changed hands over a given week."
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    Likewise, I can predict the statistical properties of white noise :-)
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    the problem is that usually the google search queries and the twitter updates happen after a crisis for example. I dont really think that people all over the world suddenly realised that Lehman would collapse and started googling it like crazy before it collapsed. More likely they did it afterwards.
Dario Izzo

Probabilistic Logic Allows Computer Chip to Run Faster - 3 views

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    Francesco pointed out this research one year ago, we dropped it as noone was really considering it ... but in space a low CPU power consumption is crucial!! Maybe we should look back into this?
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    Q1: For the time being, for what purposes computers are mainly used on-board?
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    for navigation, control, data handling and so on .... why?
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    Well, because the point is to identify an application in which such computers would do the job... That could be either an existing application which can be done sufficiently well by such computers or a completely new application which is not already there for instance because of some power consumption constraints... Q2 would be then: for which of these purposes strict determinism of the results is not crucial? As the answer to this may not be obvious, a potential study could address this very issue. For instance one can consider on-board navigation systems with limited accuracy... I may be talking bullshit now, but perhaps in some applications it doesn't matter whether a satellite flies on the exact route but +/-10km to the left/right? ...and so on for the other systems. Another thing is understanding what exactly this probabilistic computing is, and what can be achieved using it (like the result is probabilistic but falls within a defined range of precision), etc. Did they build a complete chip or at least a sub-circiut, or still only logic gates...
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    Satellites use old CPUs also because with the trend of going for higher power modern CPUs are not very convenient from a system design point of view (TBC)... as a consequence the constraints put on on-board algorithms can be demanding. I agree with you that double precision might just not be necessary for a number of applications (navigation also), but I guess we are not talking about 10km as an absolute value, rather to a relative error that can be tolerated at level of (say) 10^-6. All in all you are right a first study should assess what application this would be useful at all.. and at what precision / power levels
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    The interest of this can be a high fault tolerance for some math operations, ... which would have for effect to simplify the job of coders! I don't think this is a good idea regarding power consumption for CPU (strictly speaking). The reason we use old chip is just a matter of qualification for space, not power. For instance a LEON Sparc (e.g. use on some platform for ESA) consumes something like 5mW/MHz so it is definitely not were an engineer will look for some power saving considering a usual 10-15kW spacecraft
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    What about speed then? Seven time faster could allow some real time navigation at higher speed (e.g. velocity of a terminal guidance for an asteroid impactor is limited to 10 km/s ... would a higher velocity be possible with faster processors?) Another issue is the radiation tolerance of the technology ... if the PCMOS are more tolerant to radiation they could get more easily space qualified.....
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    I don't remember what is the speed factor, but I guess this might do it! Although, I remember when using an IMU that you cannot have the data above a given rate (e.g. 20Hz even though the ADC samples the sensor at a little faster rate), so somehow it is not just the CPU that must be re-thought. When I say qualification I also imply the "hardened" phase.
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    I don't know if the (promised) one-order-of-magnitude improvements in power efficiency and performance are enough to justify looking into this. For once, it is not clear to me what embracing this technology would mean from an engineering point of view: does this technology need an entirely new software/hardware stack? If that were the case, in my opinion any potential benefit would be nullified. Also, is it realistic to build an entire self-sufficient chip on this technology? While the precision of floating point computations may be degraded and still be useful, how does all this play with integer arithmetic? Keep in mind that, e.g., in the Linux kernel code floating-point calculations are not even allowed/available... It is probably possible to integrate an "accelerated" low-accuracy floating-point unit together with a traditional CPU, but then again you have more implementation overhead creeping in. Finally, recent processors by Intel (e.g., the Atom) and especially ARM boast really low power-consumption levels, at the same time offering performance-boosting features such as multi-core and vectorization capabilities. Don't such efforts have more potential, if anything because of economical/industrial inertia?
Juxi Leitner

Baby-by-Number: Parents' New Obsession With Data | Wired Science | Wired.com - 0 views

  • Even the folks at LeapFrog caution that electronic toys shouldn’t replace the tried-and-true childhood staples of previous generations. Plain old wooden blocks can be an incredibly valuable learning tool, says Jim Gray, a former child development researcher who now heads the learning team at LeapFrog.
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    for the dad's out there...
Nina Nadine Ridder

Top 10 Surprising Results of Global Warming | LiveScience - 5 views

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    #4 is pretty interesting 
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    first time I hear about this!!! Is there any peer reviewed paper reference to this? should impact missions like GOCE!!
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    There are (even in Science): http://science-mag.aaas.org/cgi/reprint/314/5803/1253.pdf There is also a group at UCAR (lead by S. Solomon, one of the Gods in atmospheric research) who are analyzing this effect: http://www.ucar.edu/news/releases/2006/thermosphere.shtml
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    for the drag effect, this is well known in fluid mechanics, we use the Knudsen number, which explains this phenomenon ... for a perfect gaz though!
Francesco Biscani

Pi Computation Record - 4 views

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    For Dario: the PI computation record was established on a single desktop computer using a cache optimized algorithm. Previous record was obtained by a cluster of hundreds of computers. The cache optimized algorithm was 20 times faster.
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    Teeeeheeeeheeee... assembler programmers greet Java/Python/Etc. programmers :)
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    And he seems to have done everything in his free time!!! I like the first FAQ.... "why did you do it?"
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    did you read any of the books he recommends? suggest: Modern Computer Arithmetic by Richard Brent and Paul Zimmermann, version 0.4, November 2009, Full text available here. The Art of Computer Programming, volume 2 : Seminumerical Algorithms by Donald E. Knuth, Addison-Wesley, third edition, 1998. More information here.
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    btw: we will very soon have the very same processor in the new iMac .... what record are you going to beat with it?
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    Zimmerman is the same guy behind the MPFR multiprecision floating-point library, if I recall correctly: http://www.mpfr.org/credit.html I've not read the book... Multiprecision arithmetic is a huge topic though, at least from the scientific and number theory point of view if not for its applications to engineering problems. "The art of computer programming" is probably the closest thing to a bible for computer scientists :)
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    "btw: we will very soon have the very same processor in the new iMac .... what record are you going to beat with it?" Fastest Linux install on an iMac :)
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    "Fastest Linux install on an iMac :)" that is going to be a though one but a worthy aim! ""The art of computer programming" is probably the closest thing to a bible for computer scientists :)" yep! Programming is art ;)
Joris _

Latest space jobs report still bleak | floridatoday.com | FLORIDA TODAY - 1 views

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    I found these are huge numbers, as if it is the taskforce necessary for building the shuttle from scratch ... but it is supposedly reusable!
pacome delva

Quantum computer takes on quantum chemistry - physicsworld.com - 1 views

  • The process is done 20 times to create a 20-bit binary number that represents the energy of the hydrogen molecule to a precision of about one part per million.
  • Aspuru-Guzik described the two-qubit calculation as a "baby step forward," and added that a 128-qubit system would be needed to work out the energy levels of a simple molecule such as water.
pacome delva

RHIC nets strange antimatter - 0 views

  • The antihypertriton – consisting of an antiproton, an antineutron and an antilambda particle – is the heaviest antinucleus yet produced and opens up a new realm of strange antinucluei. It could also shed light on a number of problems in astrophysics and cosmology, including the dominance of matter over antimatter in the universe.
Ma Ru

Researcher Creates 'Facebook for Scientists' - 1 views

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    and we are of course there since some time :-) and even have our own group in there ... think that Tobias has first discovered it our group is: https://www.researchgate.net/group/ESA_Advanced_Concepts_Team/ everybody welcome to join ... though Ariadnet is better
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    So if I'm already on Ariadnet, there's no need for me to join this researchgate thingy? Pheew..
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    Very active group, it has exactly one member (Leo) and exactly zero (ZERO,0!!) posts since June 13, 2008!!! Well, sounds like a very typical ACT action in order to increase the key performance indicators :D.
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    Oh come on Luzi, don't be over-pessimistic! It's just because all activity takes place on Ariadnet ;-)
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    tsk tsk typical ex-ACT criticism.. Maybe for me too from next week;P
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    WRONG! You ignore the fact that I complained already while I was yet in the ACT!! Seriously: I clicked around in "ResearchGate" a little bit, couldn't find too many interesting things. Many scientists from India, Iran etc. desperately looking for contacts, retired engineers/scientists from industry that now remember that they were once at university and also quite a number of semi-crackpots. My honest conclusion: not a must. Btw: wish you a nice post-ACT depression! Keep a stiff upper lip, esp. in case you go back to Greece...
nikolas smyrlakis

mentored by the Advanced Concepts Team for Google Summer of Code 2010 - 4 views

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    you propably already know,I post it for the twitter account and for your comments
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    once again one of these initiatives that came up from a situation and that would never have been possible with a top-down approach .... fantastic! and as Dario said: we are apparently where NASA still has to go with this :-)
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    Actually, NASA Ames did that already within the NASA Open Source Agreement in 2008 for a V&V software!
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    indeed ... you are right .... interesting project btw - they started in 1999, were in 2005 the first NASA project on Sourceforge and won several awards .... then this entry why they did not participate last year: "05/01/09: Skipping this years Google Summer-of-Code - many of you have asked why we are not participating in this years Summer of Code. The answer is that both John and Peter were too busy with other assignments to set this up in time. We will be back in 2010. At least we were able to compensate with a limited number of NASA internships to continue some of last years projects." .... but I could not find them in this years selected list - any clue?
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    but in any case, according to the apple guru, Java is a dying technology, so their project might as well ...
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    They participate under the name "The Java Pathfinder Team" (http://babelfish.arc.nasa.gov/trac/jpf/wiki/events/soc2010). It is actually a very useful project for both education and industry (Airbus created a consortium on model checking soft, and there is a lot of research on it) As far as I know, TAS had some plans of using Java onboard spacecrafts, 2 years ago. Not sure the industry is really sensible about Jobs' opinions ;) particularly if there is no better alternative!
pacome delva

Randomness is no lottery thanks to entangled ions - 0 views

  • An international team of physicists has created the first system that can produce verifiably random numbers. The technique relies on the inherent uncertainties in quantum mechanics and future versions could help cryptographers to encode information more securely than ever before.
pacome delva

Novel negative-index metamaterial bends light 'wrong' direction - 1 views

  • the first negative index metamaterial to operate at visible frequencies
  • By engineering a metamaterial with such properties, we are opening the door to such unusual -- but potentially useful -- phenomena as superlensing (high-resolution imaging past the diffraction limit), invisibility cloaking, and the synthesis of materials index-matched to air, for potential enhancement of light collection in solar cells
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    I forwarded the link to my experimental colleagues and here is the comment from Sergei (the master himself:) "this is what Igor has been doing - an array of plasmonic nanocables. This basically works as a wire-medium slab. All their epsilon and mu are rubbish." * If Sergei is as strict as in this comment, then it IS rubbish. He's not one of the notorious complainer (as e.g. myself.) * Please DO NOT FORWARD this to anybody else, Sergei's comment is NOT FOR PUBLIC USE!
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    UPDATE: I had a short chat with Sergei and Pekka, Sergei noticed that there is an increasing number of papers on metamaterials, especially in Nature and Science, which are simply wrong, this one being an example. * The idea is based on a very well known effect of wired media. What appears to be interesting about this paper is that they manage to make an optical analogue with aparently low losses. This could be interesting. * The whole interpretation as NIM, "wrong" refraction etc. is total nonsense.
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    wow, good to know ! But for the privacy you should be aware that this is a public group, so anyone has access to our comments i think !
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