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Luís F. Simões

Evolution of AI Interplanetary Trajectories Reaches Human-Competitive Levels - Slashdot - 4 views

  • "It's not the Turing test just yet, but in one more domain, AI is becoming increasingly competitive with humans. This time around, it's in interplanetary trajectory optimization. From the European Space Agency comes the news that researchers from its Advanced Concepts Team have recently won the Gold 'Humies' award for their use of Evolutionary Algorithms to design a spacecraft's trajectory for exploring the Galilean moons of Jupiter (Io, Europa, Ganymede and Callisto). The problem addressed in the awarded article (PDF) was put forward by NASA/JPL in the latest edition of the Global Trajectory Optimization Competition. The team from ESA was able to automatically evolve a solution that outperforms all the entries submitted to the competition by human experts from across the world. Interestingly, as noted in the presentation to the award's jury (PDF), the team conducted their work on top of open-source tools (PaGMO / PyGMO and PyKEP)."
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    We made it to Slashdot's frontpage !!! :)
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    Congratulations, gentlemen!
tvinko

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?
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.
Thijs Versloot

The SupraThermal Ion Monitor for space weather predictions - 4 views

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    The novel part here is that it can be scaled down to the cubesat platform. I then wondered, could we place multiple of such Cubesats in a 'decaying orbit' around the Sun? Fractionated will give spatial and temporal information which, even with a simple langmuir probe setup, can give information on density, temperature, velocity, ion energy distribution, potential.. Of course they will be lost relatively quickly, but more could be ejected from a mother ship which is orbiting at a safer distance.
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    For example like the KickSat projec https://www.kickstarter.com/projects/zacinaction/kicksat-your-personal-spacecraft-in-space Although a pc-reboot due to a radiation event in the electronics has reset the deployment timeline to approximately 2 days after re-entry... http://www.huffingtonpost.co.uk/2014/05/06/kicksat-satellites_n_5273821.html
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 _

FASTSAT performing well; launch of small satellite coming next week | al.com - 0 views

  • Being able to launch a satellite from a satellite has numerous potential benefits to the military and scientists, but those benefits depend on the smaller satellite not hitting the mother ship when it launches and going where it needs to go.If the sail can deploy as planned to its 100-square-foot size - about as big as a six-person camping tent - and can guide the smaller satellite to its planned re-entry, it would also illustrate a new way to bring satellites back to Earth and reduce orbiting space junk.
Luís F. Simões

heat shields: NASA's Orion capsule vs. SpaceX's Dragon capsule - 0 views

  • NASA has 50 years of experience with reentry capsules, but is fearful of trying something new. SpaceX has no reentry experience and chooses the most efficient engineering approach. Guess whose capsule is overweight and still sitting on the ground? Guess whose capsule completed a successful first flight yesterday?
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    Powerful contrast between the two pictures!!
Juxi Leitner

Concept for swarming "display blocks" Boing Boing - 3 views

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    please see my Flyfire entry from MIT some posts below ...
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    yeah I saw it, it's also mentioned in the article
nikolas smyrlakis

mentored by the Advanced Concepts Team for Google Summer of Code 2010 - 4 views

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    you propably already know,I post it for the twitter account and for your comments
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    once again one of these initiatives that came up from a situation and that would never have been possible with a top-down approach .... fantastic! and as Dario said: we are apparently where NASA still has to go with this :-)
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    Actually, NASA Ames did that already within the NASA Open Source Agreement in 2008 for a V&V software!
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    indeed ... you are right .... interesting project btw - they started in 1999, were in 2005 the first NASA project on Sourceforge and won several awards .... then this entry why they did not participate last year: "05/01/09: Skipping this years Google Summer-of-Code - many of you have asked why we are not participating in this years Summer of Code. The answer is that both John and Peter were too busy with other assignments to set this up in time. We will be back in 2010. At least we were able to compensate with a limited number of NASA internships to continue some of last years projects." .... but I could not find them in this years selected list - any clue?
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    but in any case, according to the apple guru, Java is a dying technology, so their project might as well ...
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    They participate under the name "The Java Pathfinder Team" (http://babelfish.arc.nasa.gov/trac/jpf/wiki/events/soc2010). It is actually a very useful project for both education and industry (Airbus created a consortium on model checking soft, and there is a lot of research on it) As far as I know, TAS had some plans of using Java onboard spacecrafts, 2 years ago. Not sure the industry is really sensible about Jobs' opinions ;) particularly if there is no better alternative!
LeopoldS

Spaceflight Now | Atlas Launch Report | Air Force spaceplane is an odd bird with a twis... - 3 views

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    Juxi are you following this one? any idea on its purpose?
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    Not that I'm an expert in the field in any way, but there are two things I could think of: 1) possibility of bringing the payload back means that it can collect huge amounts of data which wouldn't be possible to be transferred via radio in reasonable time and/or you can bring back data you don't want to be intercepted by enemy 2) I remember reading somewhere that possibility of re-entry from orbit means you can strike any country without violating the airspace of the neighbouring countries. As the project is now managed by military, a purely civil purpose can be safely ruled out in my opinion.
pacome delva

X-37B military spaceplane launches from Cape Canaveral - 1 views

  • The X-37B, which has been likened to a scaled-down space shuttle, blasted off from Cape Canaveral Air Force Station at 0052 BST (1952 EDT).
  • The X-37B, which has been likened to a scaled-down space shuttle, blasted off from Cape Canaveral Air Force Station at 0052 BST (1952 EDT). The military vehicle is unpiloted and will carry out the first autonomous re-entry and landing in the history of the US space programme.
  • In all honesty, we don't know when it's coming back for sure.
Luís F. Simões

Russian Physicists Solve Radio Black-Out Problem for Re-Entering Spacecraft  ... - 1 views

  • When spacecraft return to Earth, one of the tensest parts of the mission is the radio black out that occurs as the vehicle re-enters the atmosphere. Travelling at hypersonic speeds of between Mach 8 and 15, the spacecraft heats and breaks down molecules in the atmosphere causing a plasma to form. It is this plasma sheath that prevents radio communication.
  • Ref: arxiv.org/abs/0704.3103: Communication Through Plasma Sheaths
Dario Izzo

ESA Portal - ESA to launch two large observatories to look deep into space and time - 0 views

  • s in space, in a part of the electromagnetic spectrum still mostly unexplored. Planck is a telescope that will map the fossil light of the Universe - light from the Big Bang
    • Dario Izzo
       
      try izzo
    • LeopoldS
       
      strange entries here ? just testing the system???
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    Amazing "to look deep into space and time". What a nice pun!
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    Coooool!
LeopoldS

The Go Programming Language - 3 views

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    new programming language - hybrid between c and python .... from google .... of any interest for us?
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    See the other post for my comments....
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    sorry - did not see Juxi's entry ....
Francesco Biscani

xkcd: Future Timeline - 5 views

shared by Francesco Biscani on 18 Apr 11 - No Cached
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    Our job is now useless :P
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    this entry tells it all: "2066 - Cyprus achieves its goal"
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    > Francesco And all it took was a simple well-written google bot...
nikolas smyrlakis

KickSat: Send Tiny DIY Satellites Into Space | TechCrunch - 1 views

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    See my entry a bit earlier on this
Paul N

Microsoft Hololens, Occulus rift killer? - 1 views

shared by Paul N on 27 Jan 15 - No Cached
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    Probably old news by now, but this thing sounds so awesome it warrants an entry
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    Looks like fun! Note though, I'm always slightly annoyed when people use holography only because it sounds cool. because clearly this is not a hologram! Definition: a three-dimensional image formed by the interference of light beams from a laser or other coherent light source. I am sure this is not what is happening in these goggles.
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    I think they suspect that "hologram" would sell better than "yet-another-augmented-reality-goggle"
Ma Ru

Ambition - 0 views

shared by Ma Ru on 15 Mar 13 - No Cached
LeopoldS liked it
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    Today we released the Astro Drone app. People that have the Parrot AR drone can freely download the game. While they fly their drone in the real world, they are trying to dock to the ISS in the virtual world. But the app is more than a game. Players can choose to participate in a scientific crowd sourcing experiment that aims to improve autonomous capabilities of space probes, such as landing, obstacle avoidance, and docking. If participating, the app extracts visually salient features from the images made by the drone's camera. The features are then combined with the estimates of the drone's state and uploaded. The data is then used in a research aiming to improve robot navigation.
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    Visit the main ESA website and you'll be greeted with a 6-minute Rosetta promo movie by a kickass Polish artist... P.S. You can also find the video here. P.P.S It seems I've just discovered a way to hijack old diigo entries ;-)
Dario Izzo

Detection of Intact Lava Tubes at Marius Hills on the Moon by SELENE (Kaguya) Lunar Rad... - 0 views

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    The paper I talked about with the proof of a gigantic lava tube discovered in 2017 from data of the Japanese lunar mission
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    Given the size of this thing we may consider a project on city urban planning inside. I would see a rocket-port outside the crater, some lift systems to get in, a closed dome with artificial atmosphere where to develop the city possible trekking routes on the lunar surface, a mirror system to get sunlight in, an energy factory just outside the entry.
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