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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
johannessimon81

Google combines skycrane, VTOL and lifting wing to make drone deliveries - 6 views

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    Nice video featuring the technology. Plus it comes with a good soundtrack! Google's project wing uses a lifting wing concept (more fuel efficient than normal airplane layouts and MUCH more efficient than quadrocopters) but it equips the plane with engines strong enough to hover in a nose up position, allowing vertical landing and takeoff. For the delivery of packages the drone does not even need to land - it can lower them on a wire - much like the skycrane concept used to deliver the Curiosity rover on Mars. Not sure if the skycrane is really necessary but it is certainly cool. Anyways, the video is great for its soundtrack alone! ;-P
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    could we just use genetic algorithms to evolve these shapes and layouts? :P
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    > Not sure if the skycrane is really necessary but it is certainly cool. I think apart from coolness using a skycrane helps keep the rotating knives away from the recipient...
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    Honest question, are we ever going to see this in practice? I mean besides some niche application somewhere, isn't it fundamentally flawed or do I need to keep my window opened on the 3rd floor without a balcony when I ordered something from DX? Its pretty cool yes, but practical?
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    Package delivery is indeed more complicated than it may seem at first sight, although solutions are possible for instance by restricting delivery to distribution centers. What we really need of course is some really efficient and robust AI to navigate without any problems in urban areas : ) The hybrid is interesting since it combines the advantage of a Vertical Takeoff and Landing (and hover), and a wing for more efficient forward flight. Challenges lie in the control of the vehicle under any angle and all that this entails also for higher levels of control. Our lab has first used this concept a few years ago for the DARPA UAVforge challenge, and we had two hybrids in our entry last year for the IMAV 2013 (for some shaky images: https://www.youtube.com/watch?v=Z7XgRK7pMoU ).
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    Fair enough, but even if you consider advanced/robust/efficient AI, why would you use a drone? Do we envision hundreds of drones above our heads in the street instead of UPS vans, or postmen, considering delivers letters might be more easily achievable. I am not so sure if personal delivery will take this route. On the other hand, if the system would work smoothly, I can image that I'm send a mail with the question whether I'm home (or they might know already from my personal GPS tracker) and then notify me that they are launching my DVD and it will come crashing into my door in 5min.
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    I'm more curios how they're planning to keep people from stealing the drones. I could do with a drone army myself and having cheap amazon or google drones flying about sounds like a decent source.
Joris _

Is It Time To Revamp Systems Engineering? | AVIATION WEEK - 1 views

  • They both believe the systems engineering processes that have served the aerospace and defense community since pre-Apollo days are no longer adequate for the large and complex systems ­industry is now developing.
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    1) it has to actively work and produce a result that's what you intended 2) the design must be robust. 3) it should be efficient 4) it should minimize unintended consequences. "But we have to establish a formal, mathematically precise mechanism to measure complexity and adaptability . . . [where] adaptability means the system elements have sufficient margin, and can serve multiple purposes." "We need to break the paradigm of long cycles from design to product" some interesting questions....
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    indeed ... already hotly debated in CDF ... any suggestions in addition to what we already contributed to this (e.g. system level optimisation)
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    what is the outcome of the CDF study ? I think actually that optimisation is not at all the key point. As it is stressed in this news, it is robustness (points 2 and 4). This is something we should think about ...
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    SYSTEM OF SYSTEMS, SYSTEM OF SYSTEMS!!! :-D
Joris _

SPACE.com -- Venus Probe's Problems May Cause Japan to Scale Back - 0 views

  • We have to be more conservative to plan our next planetary mission, so it will never fail in any aspect."
  • the probe's initial failure will have a big impact on how JAXA plans future planetary missions
  • hew to more conservative ideas in the near future
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    what a shame! ambition and innovation have not been fairly rewarded ...
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    Did you try to run your algorithm on their problem as Dario suggested? I'm very curious!
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    I didn't have time yet. But formulating the failure with a MTBF or a FIT, you can easily imagine a more robust solution. Instead of one single burn, you would make several smaller burns - It will take more time and require more fuel though. Another "robust" approach is to consider weak stability boundary capture. Again it takes time, but chances of failure are lessen.
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    would be a pity indeed!
Tobias Seidl

A curvy, stretchy future for electronics - PNAS - 0 views

  • Electronics of the future will be soft and rubbery.
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    If electronics are soft and rubbery, would they maybe also tolerate launch- or landing-related vibrations better? Could we pack things more robust? Probably things get too fluffy for space engineers?
ESA ACT

Nanotube Phonon Waveguide - 0 views

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    We find that the high thermal conductivity of carbon nanotubes remains intact under severe structural deformations while the corresponding electrical resistance and thermoelectric power show compromised responses. Similar robust thermal transport against
Juxi Leitner

StarCraft AI Competition | Expressive Intelligence Studio - 4 views

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    The Expressive Intelligence Studio at UC Santa Cruz will be hosting a StarCraft competition: This competition enables academic researchers to evaluate their AI systems in a robust commercial RTS environment. The final matches will be held live with commentary. Exhibition matches will also be held between skilled human players and the top performing bots.
jcunha

Accelerated search for materials with targeted properties by adaptive design - 0 views

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    There has been much recent interest in accelerating materials discovery. High-throughput calculations and combinatorial experiments have been the approaches of choice to narrow the search space. The emphasis has largely been on feature or descriptor selection or the use of regression tools, such as least squares, to predict properties. The regression studies have been hampered by small data sets, large model or prediction uncertainties and extrapolation to a vast unexplored chemical space with little or no experimental feedback to validate the predictions. Thus, they are prone to be suboptimal. Here an adaptive design approach is used that provides a robust, guided basis for the selection of the next material for experimental measurements by using uncertainties and maximizing the 'expected improvement' from the best-so-far material in an iterative loop with feedback from experiments. It balances the goal of searching materials likely to have the best property (exploitation) with the need to explore parts of the search space with fewer sampling points and greater uncertainty.
Athanasia Nikolaou

Why mental illness is on the rise in academia - 2 views

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    Interesting discussion is going about, on how work anxiety is spreading in academia, with possible mental consequences. And with robust links to the "Doing What You Love" motto of life/work. Could be proven an unsustainable model though. Recalling of Higgs' recent declaration, that today's Academia productivity demands would be hectic for him, could point to the direction of the problem and the solution...?
johannessimon81

Computing with RNA - 0 views

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    After a discussion this morning on robust computing and possible implementations in biological systems I found this really nice result (from 2008) on molecular RNA computers that get assembled within cells and perform simple functions. Of course by having different types of computers within the same cell one could go on to process the output of the other and more complex computations could be executed... Food for thought. :-)
Thijs Versloot

New Quantum Theory to explain flow of time - 2 views

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    Basically quantum entanglement, or more accurately the dispersal and expansion of mixed quantum states, results in an apparent flow of time. Quantum information leaks out and the result is the move from a pure state (hot coffee) to a mixed state (cooled down) in which equilibrium is reached. Theoretically it is possible to get back to a pure state (coffee spontaneously heating up) but this statistical unlikelihood gives the appereance of irreversibility and hence a flow o time. I think an interesting question is then: how much useful work can you extract from this system? (http://arxiv.org/abs/1302.2811) It should for macroscopic thermodynamic systems lead to the Carnot cycle, but on smaller scales it might be possible to formulate a more general expression. Anybody interested to look into it? Anna, Jo? :)
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    What you propose is called Maxwell's demon: http://en.wikipedia.org/wiki/Maxwell%27s_demon Unfortunately (or maybe fortunately) thermodynamics is VERY robust. I guess if you really only want to harness AND USE the energy in a microscopic system you might have some chance of beating Carnot. But any way of transferring harvested energy to a macroscopic system seems to be limited by it (AFAIK).
Beniamino Abis

Self-healing plastic that regenerates mimicking blood clots - 1 views

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    A vascular synthetic system that restores mechanical performance in response to large-scale damage. Gap-filling scaffolds are created through a two-stage polymer chemistry that initially forms a shape-conforming dynamic gel but later polymerizes to a solid structural polymer with robust mechanical properties.
jmlloren

Exotic matter : Insight : Nature - 5 views

shared by jmlloren on 03 Aug 10 - Cached
LeopoldS liked it
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    Trends in materials and condensed matter. Check out the topological insulators. amazing field.
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    Aparently very interesting, will it survive the short hype? Relevant work describing mirror charges of topological insulators and the classical boundary conditions were done by Ismo and Ari. But the two communities don't know each other and so they are never cited. Also a way to produce new things...
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    Thanks for noticing! Indeed, I had no idea that Ari (don't know Ismo) was involved in the field. Was it before Kane's proposal or more recently? What I mostly like is that semiconductors are good candidates for 3D TI, however I got lost in the quantum field jargon. Yesterday, I got a headache trying to follow the Majorana fermions, the merons, skyrnions, axions, and so on. Luzi, are all these things familiar to you?
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    Ismo Lindell described in the early 90's the mirror charge of what is now called topological insulator. He says that similar results were obtained already at the beginning of the 20th century... Ismo Lindell and Ari Sihvola in the recent years discussed engineering aspects of PEMCs (perfect electro-megnetic conductors,) which are more or less classical analogues of topological insulators. Fundamental aspects of PEMCs are well knwon in high-energy physics for a long time, recent works are mainly due to Friedrich Hehl and Yuri Obukhov. All these works are purely classical, so there is no charge quantisation, no considerations of electron spin etc. About Majorana fermions: yes, I spent several years of research on that topic. Axions: a topological state, of course, trivial :-) Also merons and skyrnions are topological states, but I'm less familiar with them.
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    "Non-Abelian systems1, 2 contain composite particles that are neither fermions nor bosons and have a quantum statistics that is far richer than that offered by the fermion-boson dichotomy. The presence of such quasiparticles manifests itself in two remarkable ways. First, it leads to a degeneracy of the ground state that is not based on simple symmetry considerations and is robust against perturbations and interactions with the environment. Second, an interchange of two quasiparticles does not merely multiply the wavefunction by a sign, as is the case for fermions and bosons. Rather, it takes the system from one ground state to another. If a series of interchanges is made, the final state of the system will depend on the order in which these interchanges are being carried out, in sharp contrast to what happens when similar operations are performed on identical fermions or bosons." wow, this paper by Stern reads really weired ... any of you ever looked into this?
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    C'mon Leopold, it's as trivial as the topological states, AKA axions! Regarding the question, not me!
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    just looked up the wikipedia entry on axions .... at least they have some creativity in names giving: "In supersymmetric theories the axion has both a scalar and a fermionic superpartner. The fermionic superpartner of the axion is called the axino, the scalar superpartner is called the saxion. In some models, the saxion is the dilaton. They are all bundled up in a chiral superfield. The axino has been predicted to be the lightest supersymmetric particle in such a model.[24] In part due to this property, it is considered a candidate for the composition of dark matter.[25]"
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    Thank's Leopold. Sorry Luzi for being ironic concerning the triviality of the axions. Now, Leo confirmed me that indeed is a trivial matter. I have problems with models where EVERYTHING is involved.
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    Well, that's the theory of everything, isn't it?? Seriously: I don't think that theoretically there is a lot of new stuff here. Topological aspects of (non-Abelian) theories became extremely popular in the context of string theory. The reason is very simple: topological theories are much simpler than "normal" and since string theory anyway is far too complicated to be solved, people just consider purely topological theories, then claiming that this has something to do with the real world, which of course is plainly wrong. So what I think is new about these topological insulators are the claims that one can actually fabricate a material which more or less accurately mimics a topological theory and that these materials are of practical use. Still, they are a little bit the poor man's version of the topological theories fundamental physicists like to look at since electrdynamics is an Abelian theory.
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    I have the feeling, not the knowledge, that you are right. However, I think that the implications of this light quantum field effects are great. The fact of being able to sustain two currents polarized in spin is a technological breakthrough.
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    not sure how much I can contribute to your apparently educated debate here but if I remember well from my work for the master, these non-Abelian theories were all but "simple" as Luzi puts it ... and from a different perspective: to me the whole thing of being able to describe such non-Abelian systems nicely indicates that they should in one way or another also have some appearance in Nature (would be very surprised if not) - though this is of course no argument that makes string theory any better or closer to what Luzi called reality ....
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    Well, electrodynamics remains an Abelian theory. From the theoretical point of view this is less interesting than non-Abelian ones, since in 4D the fibre bundle of a U(1) theory is trivial (great buzz words, eh!) But in topological insulators the point of view is slightly different since one always has the insulator (topological theory), its surrounding (propagating theory) and most importantly the interface between the two. This is a new situation that people from field and string theory were not really interested in.
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    guys... how would you explain this to your gran mothers?
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    *you* tried *your* best .... ??
Joris _

Swarming spacecraft to self-destruct for greater good - space - 06 September 2010 - New... - 0 views

  • However, should one spacecraft in such a swarm begin to fail and risk a calamitous collision with another, it must sense its end is nigh and put itself on a course that takes it forever away from the swarm – for the greater good of the collective.
Joris _

American Institute of Aeronautics and Astronautics - Space and the Biological Economy - 0 views

  • the U.S. space program has a robust life science program that is diligently working to innovate new approaches, research and technologies in the fields of biotechnology and bio-nanotechnology science, which are providing new solutions for old problems – including food security, medical needs and energy needs
  • more money be allocated to develop environmentally sound and energy efficient engine programs for commercial and private aviation
  • waste water program
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  • we lack fundamental knowledge about the entire effect of the photosynthesis system on food growth, and that space-based research could provide vital clues to scientists on how to streamline the process to spur more efficient food growth
  • From the start of the space age until 2010 only around 500 people have journeyed into space, but with the advent of private space travel in the next 24 months another 500 people are expected to go into space
  • Wagner indentified prize systems that award monetary prizes to companies or individuals as an effective way to spur innovation and creativity, and urged the Congressional staffers present to consider creating more prize systems to stimulate needed innovation
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    a bunch of ideas, iinitiatives, and good points about upcoming changes in space ...
Joris _

SPACE.com -- Bigelow Aerospace Soars with Private Space Station Deals - 0 views

  • A private space company offering room on inflatable space habitats for research has found a robust international market
  • A question that continues to float through the halls of NASA and the Congress: Is there a commercial market for utilizing space?
pacome delva

Higgs hunters face long haul - 2 views

  • to reduce the chances of the LHC being derailed again by a similar accident, physicists at the Geneva lab have decided to run the collider at just half its design energy for the next 18-24 months.
  • Once the 7 TeV run is over, CERN will shut the LHC down in 2012 for a year or more to prepare it to go straight to maximum-energy 14 TeV collisions in 2013. This will be a complex job that will involve replacing some 10,000 superconducting magnet connections with more robust ones.
  • choosing to stay at lower energies is a big price to pay in terms of the Higgs search. "We will need more than twice the data at 7 TeV compared to that needed at 10 TeV to reach the same discovery potential," she says. "At this energy we can at best expect to exclude a Higgs with a mass between 155 and 175 GeV."
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    no Higgs boson before 2013... and a replacement of 10,000 superconducting magnet connections ! Reminds me of the the gravitational detectors... no detection before an upgrade in 2013...! There are the big announcements to make the cash flow... and reality !
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    Higgs is almost 81, so he should better invest in his health if he wants the Nobel prize... But who cares, it's another 5 years window where high-energy theorists can produce nonsense with no experimental evidence. They should be happy!
Loretta Latronico Poulain

Behavioural Economics? Try Biological Economics - 2 views

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    The "Biological Economics" thing is a hyping (or misunderstanding) of the BBC article. The work it refers to seems to be an application of Complex Networks theory to financial networks. I found what appear to be some of the related publications: Andrew G. Haldane (April 2009) Rethinking the financial network (further references in the footnote to page 10) Erlend Nier, Jing Yang, Tanju Yorulmazer and Amadeo Alentorn (April 2008) Network models and financial stability Funny how these issues have been repeatedly popping up at the ACT in recent weeks. This connects both with the discussions on information spreading in networks, and with roadmaps' robustness.
ESA ACT

A fast, robust and tunable synthetic gene oscillator : Article : Nature - 0 views

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    Bioluminescent bacteria - here they start glowing when the conditions change. A perfect biosensor.
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