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LeopoldS

Faster optimization | MIT News - 1 views

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    is this really as revolutionary as praised? optimisation guys please ... full paper here: http://arxiv.org/pdf/1508.04874v1.pdf
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    They use a 'separation oracle' meaning that the paper is theoretical.
Athanasia Nikolaou

A Proposal For Juno To Observe The Volcanoes Of Io - Universe Today - 0 views

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    Combination of the radio occultation method plus change in the orbital plan in order to observe new target (the volcanic outgassing from Io satellite) by passing though the magnetosphere of Jupiter. It poses a challenge in the sensitivity of the electronics. Maybe it is accepted if the risk is low. Idea for the next GTOC challenge maybe? Optimising the cost on the electronics vs the frequency of passages?
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 _

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
Joris _

Ion trap quantum computing - 0 views

  • One of the most important considerations in quantum computing is the fact that quantum computing scales polynomially, rather than exponentially, as classical computing does
  • his process would allow us to take problems of great complexity and still solve them on a humanly possible timescale. This could provide the key to modeling complex systems - especially perhaps in biology - that we can’t solve now. This would be a tremendous advantage over classical computing.
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    a follow-up question: Can quantum computer be efficient for global optimisation ?
ESA ACT

Probabilistic computing: Sacrificing Accuracy For Speed and Efficiency In Processors - 0 views

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    Via slashdot. Is that new? Must be of interest for global optimisation.
tvinko

Travelling Salesman movie - 4 views

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    related conspiracy: politicians know that P=NP but they do not let us know the proof
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    did you put money on this? I would love to see it :)
Ma Ru

The Wisdom of the Crowd in Combinatorial Problems - 5 views

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    A real scientific study...
Ma Ru

IEEE Xplore - An Adaptive Differential Evolution Algorithm With Novel Mutation and Cros... - 1 views

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    For Dario, as they quote him heavily...
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    Yep, I was told already a few months ago from Storn that this is indeed the best adaptive DE ever made. It is already in the road map for pagmo 1.2. According to pagmo it humiliates CMAES !!!
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    And in case you didn't notice, the first author is an undergraduate student.
Ma Ru

An optimization algorithm inspired by musical composition - 3 views

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    For PyGMO 2.0 ...
LeopoldS

Flies Evade Looming Targets by Executing Rapid Visually Directed Banked Turns - 4 views

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    any idea how their brain manages this ?
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    the loop might just be in the nervous system and not make it to the brain at all.
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    On this note, there is the stunningly optimised flight path of the Tiger beetle http://www.sciencedaily.com/releases/2014/04/140415133815.htm
Ma Ru

IEEE Trans. Evolutionary Computation - Special Issue on Differential Evolution - 3 views

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    Dario - perhaps worth giving a look to be up-to-date... There's even an article "Improving Classical and Decentralized Differential Evolution with New Mutation Operator and Population Topologies". They quote our CEC paper, but not the ParCo.
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    Don't know if you have full text access, so here goes the quote: "Recently, Izzo et al. designed in [27] a heterogeneous asynchronous island model for DE. They considered five islands and five DE strategies (DE/best/1/exp, DE/rand/1/exp, DE/rand-to-best/1/exp, DE/best/2/exp, and DE/rand/2/exp), and studied five distributed DEs using the same DE strategy in all the islands, and a heterogeneous model with one different DE strategy in every island. As a result, the heterogeneous model is not outstanding, but performs as well as the others."
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    Isn't it a bit a paper-killing quote?
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    :) It's in the context of a review of the work that's been done about DE with island model in general, they don't evaluate. Pity they didn't refer to the ParCo article on topologies, as it was a bit more extensive and more focused on the method (as they do in the article) rather than on the problem (as was our CEC paper, if I recall well).
LeopoldS

MUMPS : a parallel sparse direct solver - 0 views

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    of any interest to us?
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    This is an "old" stuff. It is used, as far as I remember, in IPOPT, the Interior Point OPTimiser, that I use quite often (e.g. gtoc4) ...
darioizzo2

Optimised spatial planning to meet long term urban sustainability objectives - ScienceD... - 3 views

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    for the ACT architects .... Can we do the same for the Moon Village? We brainstorm on some mathematical simplified objectives for growing the settlement (taking inputs from the modular growth, resources, terrain suitability etc ....), we define some simple rules for growth and we optimize. ..... easy peasy (i am serious)
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    i agree, with most of the parameters that would actually be really cool. but doesn't it get very messy once economy plays a large factor?
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    We can start studying the ideal case, or add also some economical constraints on the settlement layout ...
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