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The Wisdom of (Little) Crowds - 1 views

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    What is the best (wisest) size for a group of individuals? Couzin and Kao put together a series of mathematical models that included correlation and several cues. In one model, for example, a group of animals had to choose between two options-think of two places to find food. But the cues for each choice were not equally reliable, nor were they equally correlated. The scientists found that in these models, a group was more likely to choose the superior option than an individual. Common experience will make us expect that the bigger the group got, the wiser it would become. But they found something very different. Small groups did better than individuals. But bigger groups did not do better than small groups. In fact, they did worse. A group of 5 to 20 individuals made better decisions than an infinitely large crowd. The problem with big groups is this: a faction of the group will follow correlated cues-in other words, the cues that look the same to many individuals. If a correlated cue is misleading, it may cause the whole faction to cast the wrong vote. Couzin and Kao found that this faction can drown out the diversity of information coming from the uncorrelated cue. And this problem only gets worse as the group gets bigger.
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    Couzin research was the starting point that co-inspired PaGMO from the very beginning. We invited him (and he came) at a formation flying conference for a plenary here in ESTEC. You can see PaGMO as a collective problem solving simulation. In that respect, we learned already that the size of the group and its internal structure (topology) counts and cannot be too large or too random. One of the project the ACT is running (and currently seeking for new ideas/actors) is briefly described here (http://esa.github.io/pygmo/examples/example2.html) and attempts answering the question :"How is collective decision making influenced by the information flow through the group?" by looking at complex simulations of large 'archipelagos'.
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Massively collaborative mathematics : Article : Nature - 28 views

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    peer-to-peer theorem-proving
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    Or: mathematicians catch up with open-source software developers :)
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    "Similar open-source techniques could be applied in fields such as [...] computer science, where the raw materials are informational and can be freely shared online." ... or we could reach the point, unthinkable only few years ago, of being able to exchange text messages in almost real time! OMG, think of the possibilities! Seriously, does the author even browse the internet?
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    I do not agree with you F., you are citing out of context! Sharing messages does not make a collaboration, nor does a forum, .... You need a set of rules and a common objective. This is clearly observable in "some team", where these rules are lacking, making team work inexistent. The additional difficulties here are that it involves people that are almost strangers to each other, and the immateriality of the project. The support they are using (web, wiki) is only secondary. What they achieved is remarkable, disregarding the subject!
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    I think we will just have to agree to disagree then :) Open source developers have been organizing themselves with emails since the early '90s, and most projects (e.g., the Linux kernel) still do not use anything else today. The Linux kernel mailing list gets around 400 messages per day, and they are managing just fine to scale as the number of contributors increases. I agree that what they achieved is remarkable, but it is more for "what" they achieved than "how". What they did does not remotely qualify as "massively" collaborative: again, many open source projects are managed collaboratively by thousands of people, and many of them are in the multi-million lines of code range. My personal opinion of why in the scientific world these open models are having so many difficulties is that the scientific community today is (globally, of course there are many exceptions) a closed, mostly conservative circle of people who are scared of changes. There is also the fact that the barrier of entry in a scientific community is very high, but I think that this should merely scale down the number of people involved and not change the community "qualitatively". I do not think that many research activities are so much more difficult than, e.g., writing an O(1) scheduler for an Operating System or writing a new balancing tree algorithm for efficiently storing files on a filesystem. Then there is the whole issue of scientific publishing, which, in its current form, is nothing more than a racket. No wonder traditional journals are scared to death by these open-science movements.
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    here we go ... nice controversy! but maybe too many things mixed up together - open science journals vs traditional journals, conservatism of science community wrt programmers (to me one of the reasons for this might be the average age of both groups, which is probably more than 10 years apart ...) and then using emailing wrt other collaboration tools .... .... will have to look at the paper now more carefully ... (I am surprised to see no comment from José or Marek here :-)
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    My point about your initial comment is that it is simplistic to infer that emails imply collaborative work. You actually use the word "organize", what does it mean indeed. In the case of Linux, what makes the project work is the rules they set and the management style (hierachy, meritocracy, review). Mailing is just a coordination mean. In collaborations and team work, it is about rules, not only about the technology you use to potentially collaborate. Otherwise, all projects would be successful, and we would noy learn management at school! They did not write they managed the colloboration exclusively because of wikipedia and emails (or other 2.0 technology)! You are missing the part that makes it successful and remarkable as a project. On his blog the guy put a list of 12 rules for this project. None are related to emails, wikipedia, forums ... because that would be lame and your comment would make sense. Following your argumentation, the tools would be sufficient for collaboration. In the ACT, we have plenty of tools, but no team work. QED
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    the question on the ACT team work is one that is coming back continuously and it always so far has boiled down to the question of how much there need and should be a team project to which everybody inthe team contributes in his / her way or how much we should leave smaller, flexible teams within the team form and progress, more following a bottom-up initiative than imposing one from top-down. At this very moment, there are at least 4 to 5 teams with their own tools and mechanisms which are active and operating within the team. - but hey, if there is a real will for one larger project of the team to which all or most members want to contribute, lets go for it .... but in my view, it should be on a convince rather than oblige basis ...
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    It is, though, indicative that some of the team member do not see all the collaboration and team work happening around them. We always leave the small and agile sub-teams to form and organize themselves spontaneously, but clearly this method leaves out some people (be it for their own personal attitude or be it for pure chance) For those cases which we could think to provide the possibility to participate in an alternative, more structured, team work where we actually manage the hierachy, meritocracy and perform the project review (to use Joris words).
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    I am, and was, involved in "collaboration" but I can say from experience that we are mostly a sum of individuals. In the end, it is always one or two individuals doing the job, and other waiting. Sometimes even, some people don't do what they are supposed to do, so nothing happens ... this could not be defined as team work. Don't get me wrong, this is the dynamic of the team and I am OK with it ... in the end it is less work for me :) team = 3 members or more. I am personally not looking for a 15 member team work, and it is not what I meant. Anyway, this is not exactly the subject of the paper.
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    My opinion about this is that a research team, like the ACT, is a group of _people_ and not only brains. What I mean is that people have feelings, hate, anger, envy, sympathy, love, etc about the others. Unfortunately(?), this could lead to situations, where, in theory, a group of brains could work together, but not the same group of people. As far as I am concerned, this happened many times during my ACT period. And this is happening now with me in Delft, where I have the chance to be in an even more international group than the ACT. I do efficient collaborations with those people who are "close" to me not only in scientific interest, but also in some private sense. And I have people around me who have interesting topics and they might need my help and knowledge, but somehow, it just does not work. Simply lack of sympathy. You know what I mean, don't you? About the article: there is nothing new, indeed. However, why it worked: only brains and not the people worked together on a very specific problem. Plus maybe they were motivated by the idea of e-collaboration. No revolution.
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    Joris, maybe I made myself not clear enough, but my point was only tangentially related to the tools. Indeed, it is the original article mention of "development of new online tools" which prompted my reply about emails. Let me try to say it more clearly: my point is that what they accomplished is nothing new methodologically (i.e., online collaboration of a loosely knit group of people), it is something that has been done countless times before. Do you think that now that it is mathematicians who are doing it makes it somehow special or different? Personally, I don't. You should come over to some mailing lists of mathematical open-source software (e.g., SAGE, Pari, ...), there's plenty of online collaborative research going on there :) I also disagree that, as you say, "in the case of Linux, what makes the project work is the rules they set and the management style (hierachy, meritocracy, review)". First of all I think the main engine of any collaboration like this is the objective, i.e., wanting to get something done. Rules emerge from self-organization later on, and they may be completely different from project to project, ranging from almost anarchy to BDFL (benevolent dictator for life) style. Given this kind of variety that can be observed in open-source projects today, I am very skeptical that any kind of management rule can be said to be universal (and I am pretty sure that the overwhelming majority of project organizers never went to any "management school"). Then there is the social aspect that Tamas mentions above. From my personal experience, communities that put technical merit above everything else tend to remain very small and generally become irrelevant. The ability to work and collaborate with others is the main asset the a participant of a community can bring. I've seen many times on the Linux kernel mailing list contributions deemed "technically superior" being disregarded and not considered for inclusion in the kernel because it was clear that
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    hey, just catched up the discussion. For me what is very new is mainly the framework where this collaborative (open) work is applied. I haven't seen this kind of working openly in any other field of academic research (except for the Boinc type project which are very different, because relying on non specialists for the work to be done). This raise several problems, and mainly the one of the credit, which has not really been solved as I read in the wiki (is an article is written, who writes it, what are the names on the paper). They chose to refer to the project, and not to the individual researchers, as a temporary solution... It is not so surprising for me that this type of work has been first done in the domain of mathematics. Perhaps I have an ideal view of this community but it seems that the result obtained is more important than who obtained it... In many areas of research this is not the case, and one reason is how the research is financed. To obtain money you need to have (scientific) credit, and to have credit you need to have papers with your name on it... so this model of research does not fit in my opinion with the way research is governed. Anyway we had a discussion on the Ariadnet on how to use it, and one idea was to do this kind of collaborative research; idea that was quickly abandoned...
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    I don't really see much the problem with giving credit. It is not the first time a group of researchers collectively take credit for a result under a group umbrella, e.g., see Nicolas Bourbaki: http://en.wikipedia.org/wiki/Bourbaki Again, if the research process is completely transparent and publicly accessible there's no way to fake contributions or to give undue credit, and one could cite without problems a group paper in his/her CV, research grant application, etc.
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    Well my point was more that it could be a problem with how the actual system works. Let say you want a grant or a position, then the jury will count the number of papers with you as a first author, and the other papers (at least in France)... and look at the impact factor of these journals. Then you would have to set up a rule for classifying the authors (endless and pointless discussions), and give an impact factor to the group...?
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    it seems that i should visit you guys at estec... :-)
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    urgently!! btw: we will have the ACT christmas dinner on the 9th in the evening ... are you coming?
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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.
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Dropship offers safe landings for Mars rovers / Technology / Our Activities / ESA - 2 views

  • “StarTiger is a fresh approach to space engineering,” explains Peter de Maagt, overseeing the project. “Take a highly qualified, well-motivated team, gather them at a single well-equipped site, then give them a fixed time to solve a challenging technical problem.”
  • StarTiger stands for ‘Space Technology Advancements by Resourceful, Targeted and Innovative Groups of Experts and Researchers’ working within the Agency’s TRP Basic Technology Research Programme. It brings team members together on a single site to work on a set challenge, aiming to produce a working prototype by the end of the project’s time limit.
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    StarTiger: similar, yet different from the way the ACT does things. Seems like a very interesting programme.
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    Nice initiative and also a good approach, problem-oriented within a fixed time frame. Could definitely be a highly motivating approach, similar to GTOC... I think the ACT should do this more often, targeted at future technologies and/or missions. The team could be structured around 'problems' instead of 'research areas', this will promote multidisciplinary work as well, plus it will also focus activities more. The problems, or more broadly concepts, are identified by the team and a few get chosen as main activities. Subsequent RF and YGT hiring is then done to strenghten the research team. These projects have a maximum lifetime maybe of 1 year? Thoughts?
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    I'm impressed already by what an innovative group of experts and researchers was able to achieve when resourcefully targeted at coming up with the project's name...
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Boron 'buckyball' discovered - 1 views

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    Jul 13, Nanotechnology/Nanomaterials Researchers have shown that clusters of 40 boron atoms form a molecular cage similar to the carbon buckyball. This is the first experimental evidence that such a boron cage structure exists. Credit: Wang lab / Brown UniversityThe discovery 30 years ago of soccer-ball-shaped carbon molecules called buckyballs helped to spur an explosion of nanotechnology research.
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Dutch company without any managers is inspiring industry (in dutch) - 0 views

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    This dutch company, Schuberg, has no managers but instead all the employees (operating in the IT service industry) manage everything themselves. They offer IT support to KLM, Rabobank and Eneco, who are quite very reliant on the uptime of their systems. These companies rate Schuberg consistently with the highest approval. Harvard business school is now teaching this type of organizational structure. Possible new working method?
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    just like the ACT :-)
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Breaking the optical diffraction limit by a factor 3-4... ideas for telescopes? - 0 views

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    In this article the authors describe an improvement of their optical microscope techniques for which some of the received a Nobel prize in the past. They achieve resolutions far beyond the optical diffraction limit which is supposed to limit detail resolution due to quantum-mechanical effects. Their techniques include structured illuminiation (producing interference patterns), switchable fluorescent markers as well as multi-frame super resolution enhancement. Authors are able to take a single image in about 0.3 seconds which allows the study of protein processes in the cell: http://spon.de/vgTb7 . Although it is hard to imagine the application of many of these techniques for telescopes (except for super resolution), I am wondering if any of this could help building telescopes with increased optical power or reduced weight. Any ideas..?
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Why is life left-handed? The answer is in the stars - 2 views

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    While most humans are right-handed, our proteins are made up of lefty molecules. In the same way your left and right hands mirror one another, molecules can assemble in two reflected structures. Life prefers the left-handed version, which is puzzling since both mirrored types form equally in the laboratory.
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Nature: Spawning rings of exceptional points out of Dirac cones - 3 views

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    Dirac cones, a band-structure of two cones touching each other, are the key to understand graphene exceptional properties. They also appear in the theory of photon waveguides and atoms in optical lattices. In here, the study of a Dirac cone deformation in an open system (a system that is perturbed by external agents) lead to the deformation of the Dirac cone, meaning a change in the fundamental properties of the system. This change is such that strange phenomena such as unidirectional transmission or reflection or lasers with single mode (really single) operation can be achieved. Proved experimentally in photonic crystals. New way for extremely pure lasers?
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Student Confirms That There Are Enormous Tubes Of Plasma Floating Above The Earth - 1 views

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    A 60-year-old theory about the structure of the magnetic fields that surround Earth has been confirmed directly for the first time. The lead author of the paper is an undergraduate student who invented a way to view the Earth's magnetosphere in three dimensions.
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Where Life Meets Light: Bio-Inspired Photonics - 0 views

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    Octopus and optoelectronics camouflage, light bugs and LEDs, or spider webs and touch screens, ... a whole cool bunch of biomimetic stuff
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    See also the referred work "Light-extraction enhancement for light-emitting diodes: a firefly-inspired structure refined by the genetic algorithm" - quite cool! https://pure.fundp.ac.be/portal/files/11946897/paper89.pdf
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Graphene sponge can absorb light and emit energetic electrons for breakthrough solar sa... - 1 views

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    The unique structure and properties of graphene and the morphology of the bulk graphene material make it capable of not only absorbing light at various wavelengths but also emitting energetic electrons efficiently enough to drive the bulk material following Newtonian mechanics.
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    Hard to believe this should actually work, but would be quite a breakthrough indeed. I wonder, since the material should build up a significant electric potential over time, thus, pulling back the ejected electrons. Well, the paper apparently is not peer-reviewed, and I found some rather critical comments in some forums. Let's see if the experiment will be verified by another research team in due course.
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A New Way to Map the Universe - 0 views

  • A new technique might soon enable cosmologists to map the universe even when they can't pick out individual galaxies. If it works, researchers would be able to probe the structure of 500 times as much of the universe as they have studied so far.
  • With a purpose-built radio telescope, the approach could map as much as 50% of the observable universe far faster and cheaper than galaxy surveys can, Loeb says.
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    impressive
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[1010.3437] Dynamical mass generation via space compactification in graphene - 0 views

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    Is it really possible?
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    The affiliation is Saudi Arabia and Marocco, not countries famous for their contributions to physics... But nonetheless, yes this is possible, to me it even looks very plausible! But you should know that the term "mass" in this context just means a certain parameter in the dynamical equations and only has a loose relation to what we usually call "mass" in the macroscopic world.
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    ok - admit that I only read the abstract but to me the seems to be a little bit of magic happening ... even if "mass is only a certain parameter in the dynamical equations" ... I assume it still bears some "heavy" consequences in terms of their speed, interactions etc, no? and assuming that you gradually bend such a structure from a 2D to a 1D one ... does it "gain" mass gradually? all very strange to me ...
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    I think the problem is in the boundary conditions... the issue is that if you use and infinite sheet or a cylinder in the equations you always take cyclic boundary condition. If this guys are right then the mass of the quasi-particles in a crystal depends on its topology... this is a major thing...
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    BINGO!! It's almost like good ol' Kaluza-Klein...
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Bright self-cleaning surfaces inspired by nature - 1 views

  • 'the simplistic approach outlined in this work brings us a step closer to the realization of biomimetic self-cleaning and structural colour material for both functional and aesthetic applications.' 
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What Should We Teach New Software Developers? Why? | January 2010 | Communications of t... - 3 views

shared by Francesco Biscani on 15 Jan 10 - Cached
Dario Izzo liked it
  • Industry wants to rely on tried-and-true tools and techniques, but is also addicted to dreams of "silver bullets," "transformative breakthroughs," "killer apps," and so forth.
  • This leads to immense conservatism in the choice of basic tools (such as programming languages and operating systems) and a desire for monocultures (to minimize training and deployment costs).
  • The idea of software development as an assembly line manned by semi-skilled interchangeable workers is fundamentally flawed and wasteful.
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    Nice opinion piece by the creator of C++ Bjarne Stroustrup. Substitute "industry" with "science" and many considerations still apply :)
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    "for many, "programming" has become a strange combination of unprincipled hacking and invoking other people's libraries (with only the vaguest idea of what's going on). The notions of "maintenance" and "code quality" are typically forgotten or poorly understood. " ... seen so many of those students :( and ad "My suggestion is to define a structure of CS education based on a core plus specializations and application areas", I am not saying the austrian university system is good, but e.g. the CS degrees in Vienna are done like this, there is a core which is the same for everybody 4-5 semester, and then you specialise in e.g. software engineering or computational mgmt and so forth, and then after 2 semester you specialize again into one of I think 7 or 8 master degrees ... It does not make it easy for industry to hire people, as I have noticed, they sometimes really have no clue what the difference between Software Engineering is compared to Computational Intelligence, at least in HR :/
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self-healing of nano-structured materials following radiation damage - 2 views

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PLoS ONE: HAMLET Interacts with Lipid Membranes and Perturbs Their Structure and Integrity - 1 views

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    does not taste good but ....
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Nanotube 'fuzz' boosts optical performance - 0 views

  • This structure is called a "plasmonic metamaterial" because its optical properties involve surface plasmons.
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    Again some plasmonic metamaterial...
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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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