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Neuronal Networks: Computers paint like van Gogh - 1 views

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    A neuronal network trained to paint the scene of a given photograph in the style of Kandinsky, van Gogh, or Munch. Their results look quite impressive. Unfortunately the article is in German, but the English paper (with plenty of pictures) is here: http://arxiv.org/pdf/1508.06576v2.pdf Malen wie Kandinsky, wie van Gogh, wie Munch nur auf Basis einer Fotovorlage? Natürlich gibt es begabte Kunstfälscher, die das können. Jetzt aber gelingt es auch Computern, und zwar auf höchst eindrucksvolle Weise. Drei Forscher von der Universität Tübingen haben es geschafft, einem sogenannten künstlichen neuronalen Netzwerk das Malen beizubringen.
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    Impressive stuff indeed. Paper came out one week ago. Multiple independent implementations have popped out since then: * https://github.com/Lasagne/Recipes/blob/master/examples/styletransfer/Art%20Style%20Transfer.ipynb * https://github.com/jcjohnson/neural-style * https://github.com/kaishengtai/neuralart
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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
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New theory to lead to radiationless revolution - 3 views

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    Physicists have found a radical new way to confine electromagnetic energy without it leaking away, akin to throwing a pebble into a pond with no splash. The theory could have broad ranging applications from explaining dark matter to combating energy losses in future technologies.
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    I think (but am not sure) that is related to a topic that Dirk Bouwmeester's group at Leiden University works on for a while now: "Linked and knotted beams of light" http://irvinelab.uchicago.edu/papers/nphys1056.pdf
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Personal Thermal Management by Metallic Nanowire-Coated Textile - 2 views

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    By wearing clothes that have been dip-coated in a silver nanowire (AgNW) solution that is highly radiation-insulating, a person may stay so warm in the winter that they can greatly reduce or even eliminate their need for heating their home. With as extra bonus: Besides providing high levels of passive insulation, AgNW-coated clothing can also provide Joule heating if connected to an electricity source, such as a battery. The researchers demonstrated that as little as 0.9 V can safely raise clothing temperature to 38 °C, which is 1 °C higher than the human body temperature of 37 °C. How about that for personal comfort during the cold winter months
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    These applications seem more and more promising. However I wonder about the toxicity aspects of wearing this stuff and apparently some research is starting to be developed to assess that, see http://www.particleandfibretoxicology.com/content/11/1/52 showing results of pulmonary toxicity of AgNW
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    sounds almost like the asbestos story re-started :-)
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    Found an European project that takes care of the environmental, health and safety aspects of nanomaterials http://phys.org/news/2015-04-unleash-full-potential-nanomaterials.html
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Spaceflight Now | Breaking News | Prisma satellites will begin high-flying dance next week - 2 views

  • test of new formation-flying and rendezvous technologies
  • relatively low-cost technologies
  • autonomous formation-flying, meaning that we regard these two satellites as one entity
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    they presented it briefly at the 4S symposium (unfortunately really briefly..) FF is though only one of their tech demos on PRISMA
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YouTube - The latest version of the LittleDog Robot - 3 views

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    whoa!!!
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ESA Proves General Theory of Relativity Wrong???? - 3 views

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    Not again, pleeeaaase!!! Alright, you don't know the story, ask Dario or Leo...
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    he just did .... don't worry, it's already over again .... how are you btw?
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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.
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Inferring individual rules from collective behavior - 2 views

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    "We fit data to zonal interaction models and characterize which individual interaction forces suffice to explain observed spatial patterns." You can get the paper from the first author's website: http://people.stfx.ca/rlukeman/research.htm
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    PNAS? Didnt strike me as sth very new though... We should refer to it in the roots study though: "Social organisms form striking aggregation patterns, displaying cohesion, polarization, and collective intelligence. Determining how they do so in nature is challenging; a plethora of simulation studies displaying life-like swarm behavior lack rigorous comparison with actual data because collecting field data of sufficient quality has been a bottleneck." For roots it is NO bottleneck :) Tobias was right :)
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    Here they assume all relevant variables influencing behaviour are being observed. Namely, the relative positions and orientations of all ducks in the swarm. So, they make movies of the swarm's movements, process them, and them fit the models to that data. In the roots, though we can observe the complete final structure, or even obtain time-lapse movies showing how that structure came out to be, getting the measurements of all relevant soil variables (nitrogen, phosphorus, ...) throughout the soil, and over time, would be extremely difficult. So I guess a replication of the kind of work they did, but for the roots, would be hard. Nice reference though.
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hilarious publications list - 2 views

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    his day to day research experience must be relatively unusual highlights include: - Bust size and hitchhiking: a field study. http://www.ncbi.nlm.nih.gov/pubmed/18380130 'The effect of a joke on tipping when it is delivered at the same time as the bill' http://nicolas.gueguen.free.fr/Articles/JASP2002.pdf "Love is in the air": Effects of Songs With Romantic Lyrics on Compliance to a Courtship Request. http://nicolas.gueguen.free.fr/Articles/PsyMusic2010.PDF and the mostly confusing 'Presence of Various Figurines on a Restaurant Table and Consumer Choice: Evidence for an Associative Link.'
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    Now that's what I call applied science... will consider applying to his lab for a post-doc!
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China kicks off manned space station program - 2 views

  • to complete construction of a "relatively large" manned space laboratory around 2020
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NASA Goddard to Auction off Patents for Automated Software Code Generation - 0 views

  • The technology was originally developed to handle coding of control code for spacecraft swarms, but it is broadly applicable to any commercial application where rule-based systems development is used.
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    This is related to the "Verified Software" item in NewScientist's list of ideas that will change science. At the link below you'll find the text of the patents being auctioned: http://icapoceantomo.com/item-for-sale/exclusive-license-related-improved-methodology-formally-developing-control-systems :) Patent #7,627,538 ("Swarm autonomic agents with self-destruct capability") makes for quite an interesting read: "This invention relates generally to artificial intelligence and, more particularly, to architecture for collective interactions between autonomous entities." "In some embodiments, an evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy." "In yet another aspect, an autonomous nanotechnology swarm may comprise a plurality of workers composed of self-similar autonomic components that are arranged to perform individual tasks in furtherance of a desired objective." "In still yet another aspect, a process to construct an environment to satisfy increasingly demanding external requirements may include instantiating an embryonic evolvable neural interface and evolving the embryonic evolvable neural interface towards complex complete connectivity." "In some embodiments, NBF 500 also includes genetic algorithms (GA) 504 at each interface between autonomic components. The GAs 504 may modify the intra-ENI 202 to satisfy requirements of the SALs 502 during learning, task execution or impairment of other subsystems."
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iWrite - 3 views

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    another reason to buy an ipad .... :-)
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    How is this any different from the slew of existing WYSISYG LaTeX-based editors? E.g., http://www.texmacs.org/
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    wow!!!!!!!!!!!! you can write equations!!!!!!!!!!
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    "What you need: - A LaTeX installation" I guess you can buy one in Apple Store... no?
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    my understanding is that it runs on your other computer who would do all the compiling ....
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    texmacs ... and how do you install this on the iPad?
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Japan probe overshoots Venus, heads toward sun - 0 views

  • A Japanese probe to Venus failed to reach orbit Wednesday and was captured by the sun's gravitational pull
  • Akatsuki's engines did not fire long enough to attain the proper orbiting position
  • may be able to try again when it passes by Venus six years from now.
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    The usefulness of having a robust trajectory :) ... They have to wait 6 more years for another date with Venus ...
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    I agree in general but just out of the stomach: is there really an optimised trajectory that would be able to avoid this kind of scenarios when main thrusters don't perform properly? Wouldn't you in any case end up in a sun-orbiting trajectory and have to come back after years??
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    "optimised trajectory" of course not, robust definitely! It was the subject of my paper presented at the AAS (the one in San Diego) "Designing robust interplanetary trajectories subject to one temporary engine failure". The problem here is that they do not have enough fuel for a correction maneuver that would allow to come back to Venus earlier, and break for a VOI. A robust scenario could have alloted the best amount of fuel and time to be able to recover from almost all possible unplanned events. In the paper, I introduce some confidence regions such that I get the robust control for p% chance of mission success in case m% chance of problem with the propulsion system.
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    You should run your method on this scenario and see if you could get a trajectory with a shorter come back time using the same spacecraft.... would be a big selling point for a new trajectory design approach
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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?
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Special relativity passes key test - 2 views

  • Granot and colleagues studied the radiation from a gamma-ray burst – associated with a highly energetic explosion in a distant galaxy – that was spotted by NASA's Fermi Gamma-ray Space Telescope on 10 May this year. They analysed the radiation at different wavelengths to see whether there were any signs that photons with different energies arrived at Fermi's detectors at different times.
  • According to Granot, these results "strongly disfavour" quantum-gravity theories in which the speed of light varies linearly with photon energy, which might include some variations of string theory or loop quantum gravity. "I would not use the term 'rule out'," he says, "as most models do not have exact predictions for the energy scale associated with this violation of Lorentz invariance. However, our observational requirement that such an energy scale would be well above the Planck energy makes such models unnatural."
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    essentially they made an experiment that does not prove or disprove anything -big deal-... what is the scientific value of "strongly disfavour"??? I also like the sentence "most models do not have exact predictions for the energy scale associated with this violation of Lorentz invariance" ... but if this is true WHAT IS THE POINT OF THE EXPERIMENT!!!! God, physics is in trouble ....
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    hum, null result experiments are not useless !!! there is always the hope of finding "something wrong", which would lead to a great discovery. For the state of theoretical physics (the "no exact predictions" quote), i totally agree that physics is in trouble... That's what happen when physicists don't care anymore about experiments...! All you can do now is drawing "nice"graph with upper bounds on some parameters of an all tunable weird theory !
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Detecting gravitational waves by timing pulsars - 1 views

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    Undoubtedly something for Pacome...
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The Semicolon Wars » American Scientist - 2 views

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    Pretty interesting piece on computer languages.
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    Yes, very good, but I don't get what all the fuss is about... everyone knows Python is the ultimate programming language! :) Follow up reading: If programming languages were religions... (quite accurate actually) Great quote from the article you linked to: In 1975 Edsger W. Dijkstra, a major figure in the structured-programming movement, wrote a memo titled "How Do We Tell Truths that Might Hurt?" The "truths" were mostly Dijkstra's opinions of programming languages; how he told them was very bluntly. Fortran is "an infantile disorder," PL/I "a fatal disease," APL "a mistake, carried through to perfection." Students exposed to COBOL "are mentally mutilated beyond hope of regeneration," he said. "The use of COBOL cripples the mind; its teaching should, therefore, be regarded as a criminal offense."
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    Fool! You can pry my templates from my cold dead hands!
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Invisibility cloaks shield the large and visible - physicsworld.com - 1 views

  • Two independent groups of physicists have built invisibility cloaks that can shield large objects lying on a plane. These "carpet cloaks" are far closer to the intuitive idea of an invisibility cloak than devices previously built, they argue, because they hide objects that can be seen with the naked eye and do so at visible wavelengths. The cloaks are also relatively cheap and easy to make, being constructed from the natural material calcite.
  • The team used a technique known as transformation optics to design their cloak.
  • Tomas Tyc of Masaryk University in the Czech Republic, who was not a member of either group, thinks that the papers "describe important achievements in the area of experimental cloaking." But he maintains that a carpet cloak is quite different to a fully fledged Harry Potter-style invisibility cloak. He points out that a carpet cloak only really works when viewing an object – be it a rucksack or a sword on someone's back, for example – side on. Otherwise the object will appear flat but still be visible.
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Stepping Away From the Trees For a Look at the Forest | Science/AAAS - 1 views

  • An ingenious new tool triggers a cascade of new insights. In this special section, Science's news reporters and editors mark the end of the current decade by stepping back from weekly reporting to take a broader look at 10 insights that have changed science since the dawn of the new millennium.
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    For a direct link to the 10 articles, showing their abstracts, go here.
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