Skip to main content

Home/ Advanced Concepts Team/ Group items tagged Global

Rss Feed Group items tagged

Nicholas Lan

Cut EU red tape: Report from the Business Taskforce - 2 views

  •  
    some interesting recommendations part of a current discussion between the commission and some member states in a general, and apparently popular with all parties, drive to reduce bureaucracy to, among other things, stimulate innovation. Firms face a challenge. They produce superb products, offer world-class services and benefit from being able to sell to a European market of 500 million customers. But they are often encumbered by problematic, poorly-understood and burdensome European rules. The impact is clear: fewer inventions are patented, fewer sales are made, fewer goods are produced and fewer jobs are created.
  •  
    what hypocrites ... "As businesspeople, we are convinced that these and many other problems must be addressed if British and European firms are to compete in the global marketplace. We need regulation to operate in a pan-European market. We are not against regulation per se. But we need regulation that is pro-growth and pro-innovation." sure ....
Dario Izzo

Optimal Control Probem in the CR3BP solved!!! - 7 views

  •  
    This guy solved a problem many people are trying to solve!!! The optimal control problem for the three body problem (restricted, circular) can be solved using continuation of the secondary gravity parameter and some clever adaptation of the boundary conditions!! His presentation was an eye opener ... making the work of many pretty useless now :)
  • ...13 more comments...
  •  
    Riemann hypothesis should be next... Which paper on the linked website is this exactly?
  •  
    hmmm, last year at the AIAA conference in Toronto I presented a continuation approach to design a DRO (three-body problem). Nothing new here unfortunately. I know the work of Caillau, although interesting what is presented was solved 10 years ago by others. The interest of his work is not in the applications (CR3BP), but in the research of particular regularity conditions that unfortunately make the problem limited practically. Look also at the work of Mingotti, Russel, Topputo and other for the (C)RTBP. Smart-One inspired a bunch of researchers :)
  •  
    Topputo and some of the others 'inspired' researchers you mention are actually here at the conference and they are all quite depressed :) Caillau really solves the problem: as a one single phase transfer, no tricks, no misconvergence, in general and using none of the usual cheats. What was produced so far by other were only local solutions valid for the particular case considered. In any case I will give him your paper, so that he knows he is working on already solved stuff :)
  •  
    Answer to Marek: the paper you may look at is: Discrete and differential homotopy in circular restricted three-body control
  •  
    Ah! with one single phase and a first order method then it is amazing (but it is still just the very particular CRTBP case). The trick is however the homotopy map he selected! Why this one? Any conjugate point? Did I misunderstood the title ? I solved in one phase with second order methods for the less restrictive problem RTBP or simply 3-body... but as a strict answer to your title the problem has been solved before. Nota: In "Russell, R. P., "Primer Vector Theory Applied to Global Low-Thrust Trade Studies," JGCD, Vol. 30, No. 2", he does solve the RTBP with a first order method in one phase.
  •  
    I think what is interesting is not what he solved, but how he solved the problem. But, are means more important than end ... I dunno
  •  
    I also loved his method, and it looked to me that is far more general than the CRTBP. As for the title of this post, OK maybe it is an exageration as it suggests that no solution was ever given before, on the other end, as Marek would say "come on guys!!!!!"
  •  
    The generality has to be checked. Don't you think his choice of mapping is too specific? he doesn't really demonstrate it works better than other. In addition, the minimum time choice make the problem very regular (i guess you've experienced that solving min time is much easier than mass max, optimality-wise). There is still a long way before maximum mass+RTBP, Topputo et al should be re-assured :p Did you give him my paper, he may find it interesting since I mention the homotopy on mu but for max mass:)
  •  
    Joris, that is the point I was excited abut, at the conference HE DID present solutions to the maximum mass problem!! One phase, from LEO to an orbit around the moon .. amazing :) You will find his presentation on line.... (according to the organizers) I gave him the reference to you paper anyway, but no pdf though as you did not upload it on our web pages and I could not find it in the web. So I gave him some bibliography I had with be from the russians, and from Russell, Petropoulos and Howell, As far as I know these are the only ones that can hope to compete with this guy!!
  •  
    for info only, my phd, in one phase: http://pdf.aiaa.org/preview/CDReadyMAST08_1856/PV2008_7363.pdf I prefered Mars than the dead rock Moon though!
  •  
    If you send me the pdf I can give it to the guy .. the link you gave contains only the first page ... (I have no access till monday to the AIAA thingy)
  •  
    this is why I like this Diigo thingy so much more than delicious ...
  •  
    What do you mean by this comment, Leopold? ;-) Jokes apart: I am following the Diigo thingy with Google Reader (rss). Obviously, I am getting the new postings. But if someone later on adds a comment to a post, then I can miss it, because the rss doesn't get updated. Not that it's a big problem, but do you guys have a better solution for this? How are you following these comments? (I know that if you have commented an entry, then you get the later updates in email.) (For example, in google reader I can see only the first 5 comments in this entry.)
  •  
    I like when there are discussions evolving around entries
  •  
    and on your problem with the RSS Tamas: its the same for me, you get the comments only for entries that you have posted or that you have commented on ...
jcunha

AGM2015: Antineutrino Global Map 2015 : Scientific Reports - 1 views

shared by jcunha on 08 Sep 15 - No Cached
  •  
    Cool study about measuring antineutrino emissions in order to prospect composition of Earth's crust and mantle.
Nina Nadine Ridder

Wild Cape York and glittering reef - 1 views

  •  
    Really interesting bit hidden in the last paragraph: Monitoring coral bleaching from space with Envisat penetrating down to a depth of 10 m "[...] Envisat's Medium Resolution Imaging Spectrometer sensor can detect coral bleaching down to depths of ten metres, meaning Envisat could potentially map coral bleaching on a global scale."
  •  
    No, it can't :-) Since 8 April 2012 Envisat is a proud holder of the title of one of the biggest pieces of space junk out there in LEO...
  •  
    admittedly correct, so the past tense would have been a more appropriate choice... Nevertheless, plenty of data to look back at and Sentinel-3 will launch eventually! ;)
Nina Nadine Ridder

Enhanced marine sulphur emissions offset global warming and impact rainfall : Scientifi... - 0 views

  •  
    ocean fertilization might induce increased marine aerosol (DMS) emissions leading to further cooling effect but also changes in precipitation
Juxi Leitner

NTI: Global Security Newswire - China Accelerates Planning for Space Command - 0 views

  • The country would establish the "air-space operational command center" within the air force "in the near future," Chinese air force sources said.
  •  
    one more, France will have one officially by July, so who's next?
Juxi Leitner

Microsoft Shows Off 'Milo' Virtual Human | News & Opinion | PCMag.com - 0 views

  • TED, Microsoft showed off its "virtual human" technology, named Milo, designed for the company's hands-free Xbox 360 motion controller called Kinect at TED Global in Oxford. Milo is built to react to people's emotions, body movements, and voice, allowing players to interact with the virtual character.
Joris _

changement_climatique__octobre_2010.pdf - 2 views

  •  
    Report commissionned by French ministry on the question of global warming and causes - in french though.
Nina Nadine Ridder

Skeptical Science now an iPhone app - 2 views

  •  
    iPhone app with scientific assessment of arguments used by global warming skeptics
  •  
    very good idea! and it seems well done, the graphics are very clear and the literature abondant.
Nina Nadine Ridder

Top 10 Surprising Results of Global Warming | LiveScience - 5 views

  •  
    #4 is pretty interesting 
  • ...1 more comment...
  •  
    first time I hear about this!!! Is there any peer reviewed paper reference to this? should impact missions like GOCE!!
  •  
    There are (even in Science): http://science-mag.aaas.org/cgi/reprint/314/5803/1253.pdf There is also a group at UCAR (lead by S. Solomon, one of the Gods in atmospheric research) who are analyzing this effect: http://www.ucar.edu/news/releases/2006/thermosphere.shtml
  •  
    for the drag effect, this is well known in fluid mechanics, we use the Knudsen number, which explains this phenomenon ... for a perfect gaz though!
Joris _

DoD Buzz | Back Away from GPS: AF Chief - 4 views

  • develop alternatives to GPS
  • The fact that the U.S., which invented GPS and most of what depends on it (ATMs, gas pumps, trucking companies and lost spouses), would consider stepping away from the system marks a cultural and technological milestone
  • recommended that the U.S. scrap building five more GPS satellites and engage European allies on sharing their proposed Galileo global navigation satellite system
duncan barker

Scientists arguing about climate change - very funny - 2 views

shared by duncan barker on 06 Jan 11 - No Cached
  •  
    They are arguing about whether its the Sun or CO2 levels which effect global temperatures. which do you believe?
duncan barker

Video - The Great Global Warming Swindle - 2 views

  •  
    joke posting??
  • ...1 more comment...
  •  
    No. People SHOULD look at alternative views to be more informed. Criticism of areas of science is a GOOD thing, it helps science to grow. Unfortunately, when it comes to this issue, people, including ACT members have a closed mind and do not want to listen to alternative view points. But I am sure many people in the group have seen it before. Have you?
  •  
    This is why i always post crazy stuff .... its disruptive. ..... although sometimes its a joke ;)
  •  
    why not this one then? http://www.venganza.org/
Luís F. Simões

Bitcoin P2P Currency: The Most Dangerous Project We've Ever Seen - 10 views

  • After month of research and discovery, we’ve learned the following:1. Bitcoin is a technologically sound project.2. Bitcoin is unstoppable without end-user prosecution.3. Bitcoin is the most dangerous open-source project ever created.4. Bitcoin may be the most dangerous technological project since the internet itself.5. Bitcoin is a political statement by technotarians (technological libertarians).*6. Bitcoins will change the world unless governments ban them with harsh penalties.
  • The benefits of a currency like this:a) Your coins can’t be frozen (like a Paypal account can be)b) Your coins can’t be trackedc) Your coins can’t be taxedd) Transaction costs are extremely low (sorry credit card companies)
  • An individual with the name -- or perhaps handle -- of Satoshi Nakamoto first wrote about bitcoins in a paper called Bitcoin: A Peer-to-Peer Electronic Cash System.
  • ...1 more annotation...
  • * We made this term up to describe the “good people” of the internet who believe in the fundamental rights of individuals to be free, have free speech, fight hypocrisy and stand behind logic, technology and science over religion, political structure and tradition. These are the people who build and support things like Wikileaks, Anonymous, Linux and Wikipedia. They think that people can, and should, govern themselves. They are against external forms of control such as DRM, laws that are bought and sold by lobbyists, and religions like Scientology. They include splinter groups that enforce these ideals in the form of hacktivism, such as the takedown of the Sony Playstation Network after Sony tried to prosecute a hacker for unlocking its console.
  •  
    Sounds good!
  • ...9 more comments...
  •  
    wow it's frigthening! it's the dream of every anarchist, every drug, arm, human dealer! the world made as a global fiscal paradise... the idea is clever however it will not replace real money because 1 - no one will build a fortune on bitcoin if a technological breakthrough can ruin them 2 - government never allowed parallel money to flourish on their territory, so it will be almost impossible to change bitcoin against euros or dollars
  •  
    interesting stuff anyone read cryptonomicon by neal stephenson? similar theme.
  •  
    :) yes. One of the comments on reddit was precisely drawing the parallels with Neal Stephenson's Snowcrash / Diamond Age / Cryptonomicon. Interesting stuff indeed. It has a lot of potential for misuse, but also opens up new possibilities. We've discussed recently how emerging technologies will drive social change. Whether it's the likes of NSA / CIA who will benefit the most from the Twitters, Facebooks and so on, by gaining greater power for control, or whether individuals are being empowered to at least an identical degree. We saw last year VISA / PayPal censoring WikiLeaks... Well, here's a way for any individual to support such an organization, in a fully anonymous and uncontrollable way...
  •  
    One of my colleagues has made a nice, short write-up about BitCoin: http://www.pds.ewi.tudelft.nl/~victor/bitcoin.html
  •  
    very nice analysis indeed - thanks Tamas for sharing it!
  •  
    mmm I'm not an expert but it seemed to me that, even if these criticisms are true, there is one fundamental difference between the money you exchange on internet via your bank, and bitcoins. The first one is virtual money and the second one aims at being real, physical, money, even if digital, in the same way as banknotes, coins, or gold.
  •  
    An algorithm wanna-be central bank issuing untraceable tax free money between internet users? not more likely than the end of the world supposed to take place tomorrow, in my opinion. Algorithms don't usually assault women though !:P
  •  
    well, most money is anyway just virtual and only based on expectations and trust ... (see e.g. http://en.wikipedia.org/wiki/Money_supply) and thus if people trust that this "money" has some value in the sense that they can get something of value to them in exchange, then not much more is needed it seems to me ...
  •  
    @Leopold: ok let's use the rigth words then. Bitcoin aim at being a currency ("physical objects generally accepted as a medium of exchange" from wikipedia), different than the "demand deposit". In the article proposed by Tamas he compares what cannot be compared (currencies, demand deposits and their mean of exchange). The interesting question is wether one can create a digital currency which is too difficult to counterfeit. As far as I know, there is no existing digital currency except this bitcoins (and maybe the currencies from games as second life and others, but which are of limited use in real world).
  •  
    well of course money is trust, and even more loans and credit and even more stock and bond markets. It all represents trust and expectations. However since the first banks 500 years ago and the first loans etc. etc., and as well the fact that bonds and currencies bring down whole countries (Greece lately), and are mainly controlled by large financial centres and (central) banks, banks have always been on the winning side no matter what and that isn't going to change easily. So if you are talking about these new currencies it would be a new era, not just a new currency. So should Greece convert its debt to bitcoins ;P ?
  •  
    well, from 1936 to 1993 the central bank of france was owned by the state and was supposed to serve the general interest...
Christos Ampatzis

Academic publishers make Murdoch look like a socialist - 4 views

  •  
    Who are the most ruthless capitalists in the western world? Whose monopolistic practices make Walmart look like a corner shop and Rupert Murdoch a socialist? You won't guess the answer in a month of Sundays. While there are plenty of candidates, my vote goes not to the banks, the oil companies or the health insurers, but - wait for it - to academic publishers.
  •  
    fully agree ... "But an analysis by Deutsche Bank reaches different conclusions. "We believe the publisher adds relatively little value to the publishing process … if the process really were as complex, costly and value-added as the publishers protest that it is, 40% margins wouldn't be available." Far from assisting the dissemination of research, the big publishers impede it, as their long turnaround times can delay the release of findings by a year or more." very nice also: "Government bodies, with a few exceptions, have failed to confront them. The National Institutes of Health in the US oblige anyone taking their grants to put their papers in an open-access archive. But Research Councils UK, whose statement on public access is a masterpiece of meaningless waffle, relies on "the assumption that publishers will maintain the spirit of their current policies". You bet they will. In the short term, governments should refer the academic publishers to their competition watchdogs, and insist that all papers arising from publicly funded research are placed in a free public database. In the longer term, they should work with researchers to cut out the middleman altogether, creating - along the lines proposed by Björn Brembs of Berlin's Freie Universität - a single global archive of academic literature and data. Peer-review would be overseen by an independent body. It could be funded by the library budgets which are currently being diverted into the hands of privateers. The knowledge monopoly is as unwarranted and anachronistic as the corn laws. Let's throw off these parasitic overlords and liberate the research that belongs to us."
  •  
    It is a really great article and the first time I read something in this direction. FULLY AGREE as well. Problem is I have not much encouraging to report from the Brussels region...
nikolas smyrlakis

How Much More Rain Will Global Warming Bring? -- Wentz et al. 317 (5835): 233 -- Science - 2 views

  •  
    following the previous link
Friederike Sontag

CFC Replacements Intensify Climate Concerns - 0 views

  •  
    "But researchers say what's good for ozone is bad for climate change. In the atmosphere, these replacement chemicals [replacements for CFCs] act like "super" greenhouse gases, with a heat-trapping power that can be 4,470 times that of carbon dioxide." Havent't heard of this before...
« First ‹ Previous 61 - 80 of 102 Next › Last »
Showing 20 items per page