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johannessimon81

World's largest OTEC power plant planned for China - 1 views

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    I wonder how much energy you can extract from the ocean in a responsible way... Mixing up different thermal layers would probably a quite an influence on ecology.
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    The last available assessment report on the ecological impact seems to date from 1981 which would need to be brought up to current standards. On the other hand, this system could have a positive influence on fish population as deep cold water brings nutrients to the surface. The cold water could also be used to lower sea surface temperatures and affect hurricane genesis!
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.
Luís F. Simões

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.
Joris _

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
pacome delva

981.pdf (Objet application/pdf) - 6 views

shared by pacome delva on 14 Dec 09 - No Cached
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    Where do you want to go to do academic research and still have a decent salary ? certainly not sweden, France or Germany... prefer the UK, US or the top... Switzerland !
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    Where do you want to go to do academic research and still have fun? Where can you really do research instead of becoming an overpaid secretary? If you want to get rich go and work in investment banking...
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    well.. i'd better live decently than get rich... which is not possible in Paris (take 1680 euros for one family and a 1000 euros rent, minus all normal expenses (health, car, insurance, ...), it's difficult to finish the month...) Without mentioning that in France you would become an underpaid secretary...!!! My ex phd director is a professor and she doesn't even have a secretary to manage the 150 applications to the master she is in charge... My experience would rather say that the salary and the time you have for research are quite decorrelated.
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    Sure, 44k for a full professor, that's a bad joke! Just my experience from conferences: high saleries do not make good research, I rather suspect there's something like an optimal salery. People with too high saleries often seem to feel obliged to make much noise (whatever the reason might be), the result is not research but PR campagns.
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    I agree ! Just a correction, net salary for a full professor starting in France: 36456 euros/year... For a McF (equivalent junior prof.): 20160 euros/year, and of course a shitload of admistrative tasks and teaching. I don't know why i still dream to have a position...?
Luzi Bergamin

Prof. Markrams Hirnmaschine (Startseite, NZZ Online) - 2 views

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    A critical view on Prof. Markram's Blue Brain project (in German).
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    A critical view on Prof. Markram's Blue Brain project (in German).
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    so critical that the comment needed to be posted twice :-) ?
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    Yes, I know; I still don't know how to deal with this f.... Diigo Toolbar! Shame on me!!!
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    Would be nice to read something about the modelling, but it appears that there is nothing published in detail. Following the article, the main approach is to model each(!) neuron taking into account the spatial structure of the neurons positions. Once achieved they expect intelligent behaviour. And they need a (type of) supercomputer which does not exist yet.
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    As far as I know it's sort of like "Let's construct an enormous dynamical system and see what happens"... i.e. a waste of taxpayer's money... Able to heal Alzheimer... Yeah... Actually I was on the conference the author is mentioning (FET 2011) and I have seen the presentations of all 6 flagship proposals. Following that I had a discussion with one of my colleagues about the existence of limits of the amount of bullshit politicians are willing to buy from scientists. Will there be a point at which politicians, despite their total ignorance, will realise that scientists simply don't deliver anything they promise? How long will we (scientists) be stuck in the viscous circle of have-to-promise-more-than-predecessors in order to get money? Will we face a situation when we'll be forced to revert to promises which are realistic? To be honest none of the 6 presentations convinced me of their scientific merit (apart from the one on graphene where I have absolutely no expertise to tell). Apparently a huge amount of money is about to be wasted.
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    It's not just "Let's construct an enormous dynamical system and see what happens", it's worse! Also the simulation of the cosmological evolution is/was a little bit of this type, still the results are very interesting and useful. Why? Neither the whole cosmos nor the human brain at the level of single neurons can be modelled on a computer, that would last aeons on a "yet-to-be-invented-extra-super-computer". Thus one has to make assumptions and simplifications. In cosmology we have working theories of gravitation, thermodynamics, electrodynamics etc. at hand; starting from these theories we can make reasonable assumptions and (more or less) justified simplifications. The result is valuable since it provides insight into a complex system under given, explicit and understood assumptions. Nothing similar seems to exist in neuroscience. There is no theory of the human brain and apparently nobody has the slightest idea which simplifications can be made without harm. Of course, Mr. Markram remains completely unaffected of ''details'' like this. Finally, Marek, money is not wasted, we ''build networks of excellence'' and ''select the brightest of the brightest'' to make them study and work at our ''elite institutions'' :-). I lively remember the stage of one of these "bestofthebest" from Ivy League at the ACT...
Joris _

DARPA Solicits Ideas For Its Hundred-Year Starship Project | Popular Science - 4 views

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    I just can't see how their way of finding non-state funding for a 100 year project could work but would be happy to be surprised positively ...
LeopoldS

2009/05/05 > BE Russie 20 > Vers un système de navigation fondamentalement no... - 0 views

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    Pulsar navigation - now studied by the Russians about 6 years after our study of them ... :-)
pacome delva

Molecular Currents - 0 views

  • European researchers have measured the electrical conductance between a single pair of precisely oriented C60 molecules.
  • For the ultimate in miniaturization, researchers want to learn all they can about using molecules in electronic circuits. They have measured currents between molecules but not with a precise understanding of the configuration and positions of the molecular electrons.
Juxi Leitner

Google's Go: A New Programming Language That's Python Meets C++ - 6 views

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    Big news for developers out there: Google has just announced the release of a new, open sourced programming language called Go. The company ...
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    Ugh... no operator overloading, no efficient generic programming and no lambda expressions... Only time will tell, but I don't understand who the intended audience is: I think that Python guys won't care about the (supposedly) increased performance (and you can interface C/C++ with Python easily) and that C++ programmers (I mean, the hardcore serious C++ Boost-like programmers, no the Java-like whiners :P) won't have their beloved templates pried from their cold dead hands with ease.
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    yeah though I think especially operator overloading is not going to be a main problem, it is as with the JS library though quite thinkable that lots of users will switch or use it (or being put to use it...) because it is done by Google
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    Having Google backing it will certainly help, even though they are presenting it as a "system level" (i.e., hard-core) language, and in that domain it is much more difficult to bullshit your way to a position of relevance. Look at Java: Sun pushed it like hell and it is certainly widely used in many contexts (corporate, web and embedded markets mostly), yet it completely failed to win the hearts of "open-source" developers (or, more generally, of those developers who are not forced to use it by virtue of some management-driven decision).
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    "or, more generally, of those developers who are not forced to use it by virtue of some management-driven decision" completely agree with that!!
duncan barker

Now is your Chance to Pursue a Career in CHEESE !!!!!!!! - 5 views

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    "Application of scientific principals for improvement of quality of reduced-fat, reduced-salt cheese" As far as I know, fat and salt content in food correlates *positively* with the taste, so the project is against food quality...
LeopoldS

Evolution: Selection for positive illusions : Nature : Nature Publishing Group - 4 views

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    Let's keep going then ...
Athanasia Nikolaou

Aquifer discovered enclosed in Greenland ice sheet - 2 views

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    As the researchers desribe, the aquifer found is defined as a basin filled with aged snow (firn) that was saturated with water trapped within its porous structure. More ice cores to study! But in that case the time sequence along the length of the cores - to be extracted- would not be monotonic, as was the case in the dry cores we analysed. That's because there is constant input of surface water percolating through the ice-sheet to reach the depth of the aquifer, and since it flows downward its temperature could affect its partial pressure => its vertical position along the core
H H

Lockheed Claims Breakthrough on Fusion Energy - 3 views

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    Lockheed Martin Corp said on Wednesday it had made a technological breakthrough in developing a power source based on nuclear fusion, and the first reactors, small enough to fit on the back of a truck, could be ready in a decade.
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    Is positive news definitely, but when it comes to fusion energy being skeptic is the wisest course of action. On the back of a truck basically means that the energy density of the device is such that the surface energy of a (steady state) plasma is beyond currents materials limits. It is probably a pulsed (ignitor-type) device, which are prone to instabilities. That could therefore refer to their breakthrough claim, of which they hardly say anything though. Lets see
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    Since there were already a lot of false alarms on the field, one should definitively be careful about it. However not a single detail about its structure or how it works in this new... Here http://www.fusenet.eu/node/400 you can find a bit more of information about it.
Christophe Praz

Gigantic Ocean Vortices Seen From Space Could Change Climate Models | Science | WIRED - 5 views

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    True! Half the Phd Positions offered are in studying eddy variability. It links to resolving the - yet another holy grail - problem of turbulence.
Paul N

Have We Been Interpreting Quantum Mechanics Wrong This Whole Time? - 6 views

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    "The experiments involve an oil droplet that bounces along the surface of a liquid. The droplet gently sloshes the liquid with every bounce. At the same time, ripples from past bounces affect its course. The droplet's interaction with its own ripples, which form what's known as a pilot wave, causes it to exhibit behaviors previously thought to be peculiar to elementary particles - including behaviors seen as evidence that these particles are spread through space like waves, without any specific location, until they are measured." Pilot-wave theory reresurrected. Maybe something for the next "fundamental" :P physics RF?
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    And for the next 'Experimental Physics Stagiaire' position why not try to do "Unpredictable Tunneling of a Classical Wave-Particle Association" http://stilton.tnw.utwente.nl/people/eddi/Papers/PhysRevLett_TUNNEL.pdf, there are some rumors online that the results of Yves Couder Experiments can be reproduced with simple DIY vibrating tables! It is very funny to see the videos of the MIT's replication of this experiment (with lightening legends for those who are uncomfortable with the concepts involved https://www.youtube.com/watch?v=YF5iHQMjcsM)
Thijs Versloot

Is increased light exposure from screens and phones bad for your health? @Wired - 1 views

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    As Stevens says in the new article, researchers now know that increased nighttime light exposure tracks with increased rates of breast cancer, obesity and depression. Correlation isn't causation, of course, and it's easy to imagine all the ways researchers might mistake those findings. The easy availability of electric lighting almost certainly tracks with various disease-causing factors: bad diets, sedentary lifestyles, exposure to they array of chemicals that come along with modernity. Very difficult to prove causation I would think, but there are known relationships between hormone levels and light.
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    There is actually a windows program called flux, that changes the temperature on your screen to match normal light cycles. When the sun sets it switches to a "warmer" more reddish tint on your screen to promote sleepiness. The typically bright blue/neon white settings of most pc settings is quite "awakening" and keeps your brain running for longer. This impacts your sleeping patterns and all the consequences of that. Amazingly, this flux thing does have an effect. That being said, I wouldn't be too quick to blame it all on PC/artificial lighting time. Sedentary lifestyles, etc can very well place one in a position of long term pc/phone usage so it's quite hard to draw a causal link.
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    nice - also exists for MAC btw: https://justgetflux.com/news/pages/mac/
marliesarnhof

MIT and newly formed company launch novel approach to fusion power | MIT News - 1 views

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    Scientists anticipate the output would be more than twice the power used to heat the plasma, achieving the ultimate technical milestone: positive net energy from fusion.
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