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  1. EGO - VIRGO on Gravitational Wave Detection Imminent? · · Score: 5, Informative
    The european project is called EGO VIRGO , and it was completed some years ago. I had a chance of visiting the facility, just months before they sealed it down. The visit was a geek honeymoon with the best in contemporary advanced science. Before reading my report here, please read the summary at their website; you may also want to browse around this nice informational site. Then here following are some souvenirs that are pure technical delight (please forgive any mistake, the visit was 3 years ago):
    • The vacuum tubes are 3km long, and must be perfectly linear (since a laser is traveling in them): due to earth curvature, at the middle point they are ~1meter lower w.r.t. to the ground than at the end ! (and you can see this!)
    • the laser light travels back and forth ~40 times; suppose you would use a normal mirror, reflecting 99% of the light: summing up, you would only get 60% of the light . To avoid this problem, they built a special mirror reflecting 99.999% of the light; this mirror is made of successive layers of semiconductors, each with appropriate reflective index, each ~1 wavelenght in depth. This mirror is so advanced that they had to build a special facility in France to build it (no existing company could manufacture it!)
    • presence of the air in tubes would diffract light, so these tubes are more vacuum than the vacuum in outer space (solar system type). This is very difficult to achieve: tubes are made of stainless steel; steel usually entraps hydrogen, that then evaporates for years; to keep good vacuum, they would have needed a huge number of vacuum traps to capture these atoms of hydrogen, and that would boost the cost of the project. They instead chose to "cook the tubes" to evaporate the hydrogen; to this end, they connected power transformators to achieve a power of ~40MW and connected it to the tubes, so that they heated up by electrical resistence (and kept cooking for some days). This was costly but it saved them a lot of money overall. If you could peek below the blue roofing, you would indeed see that the inner tube is red.
    • the VIRGO facility was a strange place: it was perfectly clean and at the same it looked dirty. I explain the oximoron: while building that project, free dust was an enemy; for this reason, there were a lot of dust traps around, that is, glueish carpets; those were of course all dirty! For the same reason, we had to wear overalls and shoe coverings, and there were a lot of air pumps that were filtrating air and keeping positive pressure in the compound.
    • that reminds me: they had to build a company to build the tube pieces, (and the compay "precooked" the pieces before shipping). They also built a robot that would solder them; this robot "chews" what it does not need, since "chewing" does not create dust.
    • if you ever fly above Pisa, look down: you can easily spot VIRGO from the airplane
  2. Re:Can someone please explain this (dumbed down)? on Gravitational Wave Detection Imminent? · · Score: 2, Interesting

    the french-italian project VIRGO has two arms , each 3000 METERS long.
    BTW, whenever you here someone speaking of physics and using feets , you should doubt that s/he knows anything about the subject.

  3. batteries on A Clock That Runs for 10,000 Years · · Score: 1

    If I want to buy my own, do I have to buy all batteries in advance too?

  4. ASUS in Italy, not in USA on AMD and Intel Notebooks Head to Head · · Score: 3, Interesting

    I live in Italy, and often travel to USA: I noted that ASUS notebooks (that are quite common here - my university also bought a dozen to lend to students writing thesis) are not usually found in USA (actually it was a professor there who also noted and commented "I see all you italians arriving with ASUS notebooks that here are nowhere to be found). I wonder why.

  5. Re:Wow! What a question to ask on Slashdot... on Hackers, Spelling, and Grammar? · · Score: 1

    The original posting about the scrambling of letters claims that there was a "university research" proving that "the brain does not use internal letters to recognize words".
    Meanwhile this has become kind of a urban legend, and from time to time I receive an e-mail reporting this idea (usually, in Italian), by a friend who is, lets say, surprised by this amazing scientific discovery.

    Me, I think that there is nothing "scientific" in this claim.

    My two objections are:
    1)At that time I wrote a python script where I could tune the amount of randomness injected in the text, vs keeping the letters in original order, vs putting them in reverse : it seemed that a combination of "putting the letters in reverse" and "randomize" was the hardest to read, and even English would sometimes become unreadable.
    I have the script at home, I will post it in the afternoon.

    2) the scrambling trick works well in English where most words are short: words with 2 or 3 letters are unaffected, and 4,5-letter words are hardly affected (as in the post above).

    It is very different in languages with long words: if you know Italian, try reading this:

    il peistndere del ciglnisoo dei msrtniii bnsucorlei ha fetnlnmaie
    cstaefsnoo che il pttdooro itnreno cceresrà mtloo
    mneo del petsivro ( e mtloo mneo dllea midea dllea cntuimoà eerpoua ) ;
    per non armtaneue le istopme dtrteie ( e pdreree la fcicaa e le eoinezli )
    pedroecrà stieamntdepe ad atearnmue i blllezai
    ( cmoe il blloo sui ctnoi certnroi ) e smeecatnaitsmtie
    con il carelclnae i srizvei pcbilbui e ongi atrlo bicifeneo che la
    rpbiclbuea ci ceecvdnoa in cbimao dlel ' eosrbso
    fclasie ( stinaà slouca e qatnuo atrlo ) - alla fcicaa
    dglei ereettli berhscii che lo hnnao
    vttaoe alle uimtle enzoieli ; ctnereapnomatemnoe
    piegruosrà con l ' asubo dllea poinszioe che opcuca ,
    ( dptttuooo , ltealnmgee ) per antrameue i porpri
    bfcienei : pvtaore a mevtrtei nei pnnai di mcdoruk
    che pgaa di tscaa sua ongi ddeocer che voi utase , mtrnee
    i ddceoer per la tolnsivieee dlaitgie tsterrree li pgaa
    lo stato ( ma i sldoi per le prtitae di clicao sul dtalgiie
    trestrree li iscsana il clevriaae )

    (if you dont know Italian, then trust me: it is unreadable)

    Conclusion: it is amazing how easily people are gullible by what seems scientific and instead it is not.

  6. Re:Wow! What a question to ask on Slashdot... on Hackers, Spelling, and Grammar? · · Score: 1

    if 100$/3 = 33$, can I have that extra dollar?

  7. Re:Mail to debian-announce; news on www.debian.org on Debian 3.1 (Sarge) Released · · Score: 2, Informative
    No, you got it wrong. The best recommended way to upgrade is to use aptitude; and you should use the version of aptitude in Debian 3.1; a very short checklist for the upgrade is:
    • if you do not have aptitude installed, install the one from the Debian 3.0 (codename woody), and install the one from the latest update 3.0r6; you may use the command # apt-get install aptitude
    • change /etc/apt/sources.list to point to Debian 3.1 (codename sarge)
    • # apt-get update
    • # aptitude install aptitude
    • if you use doc-base, #aptitude install doc-base
    • aptitude -f --with-recommends dist-upgrade
    I strongly recommend that you read chapter 4 in the release notes
  8. Re:Not a true test. on Morse Coders Beat SMSers · · Score: 1

    Beat that!
    Easy. In Italy, many people own 2 cell phones (one for work, another for own use) and I know people who own (and use) 3 cell phones: work, old home GSM and new home UMTS. (They cannot drop the old GSM own phone, because they gave the number to lotsa people).
    So it happens that I see people talking on two phones at the same time. And I saw one guy talking on two phones in MARTA in Atlanta, in May, as well.
    BTW, up to some time ago, Italy and Finland where on top of cell usage in the world. Kids in Italy get their first cell when they are in junior school. In 2003 , 97% of girls and 92% of kids age 14 had (and used) a cell phone, according to this report .
    Another curiosity. Text messaging is the drivin factor in younger people choice of cell operators. Many TV commercials by cell operators in Italy are ads for discounts on mass text messaging: pay a monthly, send as many messages as you want. My younger brother is 17; recently he had to switch cell operator, since most of his class friends were using a different one, they had one of these mass discounts, and were sending him tens of messages a day; he was obliged to answer, and it was too costly (he was paying a fixed amount for each message).

  9. at San Francisco on Airport Screeners could see X-rated X-rays · · Score: 2, Interesting

    the 10th of May, I was to get on a plane in San Francisco airport, and I was picked up from the security line; I was told to enter in a new security machine that looked like a blue telephone booth with GE logos on one side; I got inside, doors closed, then there was a burts of pressurized air, and then my fingers started tickling... I dont know if it was exactly the X-ray device that is in that article, but sure it was eery. And, no, I could not peek at the security screens, they wont let me do it, neither they would explain what I was subjected to.

  10. wrong journal on Self-Replicating Robots · · Score: 1

    Great feat. They only got the journal wrong: this had better be published in "unnature".

  11. 1st: keep data encrypted on Secure Hard Drive Deletion Appliance? · · Score: 1

    As a first step, you should keep the data encrypted on all your hard drives while you are using them (both Linux and Windows/NTFS will enable you). Then, when you want to reuse them, you erase them with the best tool around. If someone will try to recover data from that HD, they will get, at most, fragments of encrypted data: not very informational.

  12. Re:wow on Gnome 2.10 Sneak Peek · · Score: 1

    indeed Debian had planned a time-back-port server (that would precompile the binary packages before the upstream authors had finished writing the software) but the project was canceled due to the lack of tachionic processors.

  13. Re:What's the downside to using X11? on Aqua OpenOffice.org v2.0 Cancelled · · Score: 1

    > it's really difficult to use X11 when you're
    > used to the consistency of native OSX (Cocoa or
    > Carbon to a certain extent) applications. i.e.:
    > All OSX apps have similar places to go for
    > preferences, to open/save files, edit, help,
    > etc. Plus keybindings and mouse behavior
    > are all similar.

    Those people who find it "really difficult" to
    find a menu item probably have so many problems
    using their PC that they will not even be able
    to start OpenOffice, let alone notice that it
    is X11 and not native.

  14. Re:Acutally, it runs Linux! on ASUS Barebones: Multimedia Even Sans Hard Drive · · Score: 1

    if the software used for on is based on Linux, there should be somewhere in ASUS website a place to download the source code. Where is it? I don't see it anywhere: this means the ASUS is violating the GPL license (or it is not using Linux).

  15. wasteful on Lego Logic Gates · · Score: 1

    I think that starting from logic gates to accomplish things in Lego is a waste. There are usually more legoish ways to do the same thing.
    EG, when I was very young I assembled a LEGO calculator that would compute simple additions; unfortunately I do not remember how it worked, but I am pretty sure it did not use gates (at the time I did not know what gates where, I did not even know what " digital" meant).
    ps: if you do not believe me, ask confirmation to my parents: they are the ones bragging this memory around; I personally had at a certain point completely forgotten the Lego calculator.

  16. Re:Large Format film cameras on "Dream Team" to Create Gigapixel Photo System · · Score: 1

    > archival without color degradation
    that is, assuming that the medium on which you archive your digital pictures is everlasting - but this is probably not the case.
    The 30 years old slides that I find in my home are still reasonably good looking - yes, they do show some colour degradation, but they are basilarly OK. Do you trust your CDROMs as well? Well, you should not : plenty of sources are reporting that the expected lifetime of your home-burnt CDROMs may be much less. When your CDROMs will be too worn out to be readable, my color slides will be still there for my nephews to view.

  17. CNNMoney dumb security quiz on Latest Version of MyDoom Exploits New IE Flaw · · Score: 1

    While I was reading the article in CNNMoney, I saw and run the at "security quiz" ... only to find it quite dumb, and funny; so I wrote this open letter to the authors of the quiz, that I want to share with you /.ers

  18. make ? on TCCBOOT Compiles And Boots Linux In 15 Seconds · · Score: 1

    I have no time to test it, still I have this question in mind: what about 'make' , 'ldd' and all the other programs that are used in building the kernel? are they all included in the 138Kb that are loaded by the boot loader?

  19. no brakes to Bill brain! on IE Holes Not Microsoft's Fault, Says Bill · · Score: 1

    Suppose my favourite carmaker sells me a car that explodes when I hit the brakes. I guess that, by Bill Gates' logic argument, I would be in fault for braking with third party boots on.

  20. a zip vulnerability !?!? on Ten Security Bulletins From Microsoft · · Score: 1

    the funniest part is that most brands of the antivirus sw that is installed in mail server would consider .zip attachment to be safe, and would mail me in disdain when I send .exe attachments, asking for it to be encapsulated in a zip; next time I will reply them with a .zip that exploits WInXP to its a**

  21. CPU scaling on Less Might Be More · · Score: 5, Interesting

    As the article suggest, I would love to see a desktop PC running on a Pentium M (or any other mobile version of a CPU): less heat, less power, reasonable performances.

    It would be also very good if desktops' MB and CPU may implement frequency and voltage scaling on the CPU (as is done in notebooks).
    Unfortunately most desktop systems do not allow it (but I heard that some newer models will).

    I use Linux on my notebook, and I have instructed the daemon "cpufreqd" to scale down on voltage (when the CPU is not very busy) *even* when I am on AC. This way, the CPU operates at an average of 60Celsius (compared to the 70C that I see under WindowsXP): saving the heat is very nice, the fan operates much less, less noise; and you can really keep your laptop on the lap.

    Moreover: do you know that CPUs evaporate? Yes, they run so hot that the tiny metal strips forming the VLSI circuitry do evaporate, (or if you prefer, diffuse) : if you keep your desktop on 24/7, in ~2 years, a Pentium or Athlon at 3000Mhz will stop working....
    But if I could scale it down when I do not need the CPU full power (and this means, most of the time) the problem would be much diminished.

    Summarizing: CPU scaling = less heat, less power, less AC bill, more life of CPU

  22. BabyBot on LivingCreatures- The Beginning Of 'I, Robot?' · · Score: 2, Interesting

    the University of Genova (Italy) has a project on a baby-robot, that is quite more advanced than that

  23. forget blades! on Building A Homebrew Robotic Lawnmower? · · Score: 1

    I would never use blades in a robotic lawnmower: blades are way too dangerous! Nobody that I know uses lawnmowers with blades anymore, at least for a reasonable sized garden.
    The lawnmower that I use do not use blades, but a nylon (or iron) string; the cord is rotated very very fast: this cuts weed and grass, but not trees and fingers (it will injure a limb, but not cut it). see picture The nylon cord is wind upon a small spinning cylinder : the downside is that you need to unwind a new piece of the cord from time to time (in particular if it touches a rock or any hard object), but I am told that newer models would do this automatically. (actually, if you hit a rock with a blade lawnmower, I guess that the blade would be damaged too).

  24. nice, but who's pet is it? on Minix from Scratch Project Established · · Score: 1

    very nice idea, but who is going to play with it? Most hackers are already playing with Linux... so this project looks like GNU Hurd: a very interesting kernel on the paper, but lacking the big number of developers-users that write device drivers for Linux.
    BTW: what about a "Linux adapter" to use device drivers written for Linux with other kernels?

  25. good translation on Rome Moving to Linux · · Score: 1

    the babelfish translation is horrible in some points. here are some corrections
    Beginning from May, the free software will enter in Campidoglio
    The Gramaglia city council member: "political Choice, not against Microsoft"
    The municipality of Rome moves slowly towards Linux
    "We want to give a contribution to the diversification"
    by ALESSIO BALBI
    ROME - "We clarify at once: we are not against Microsoft ". Mariella Gramaglia, city council member, appointed to the Communication, of the Municipality of Rome, wants to place in the just perspective what many see like the next slap arranged from the open source movement to Bill Gates and associates: beginning May, Linux will begin to replace Windows in the computers of the administration of Rome, placing Rome on the same road of Monaco and others that, in Europe and the world, have decided to entrust themselves to the free software.
    A big hit for Linux and its supporters. And the risk of one ugly smack for the pockets and the image of Microsoft. But the Roman one is however only, for now, a cautious and gradual experiment: "the first tests will be on the e-mail, on the agenda software and on the data sharing", the Gramaglia city council member explains. Also, the forum and the newsgroup that the citizens use to communicate with the Municipality (through the Web portal) will be been involved in the experimentation.
    Opening to Linux, the Campidoglio (=the house of Municipality) wants to supply its contribution to the debate on the diversification and the entry of new actors in the market of the software. "So far , ours can be defined one political choice", declares Gramaglia. A choice that, in this case, has met a bipartisan agreement: "the debate on the free software has been carried ahead from parliamentarians of the left, like senator Cortiana and the Folena member of parliament", explains the city council member. "But also in the right (and I think of minister Stanca) the importance of introducing open source in Public Administration is emphasized".
    Political issues apart, passing from the proprietary software to free one would translate in a good saving of money for the community. "But this probably will happen only in the medium term", specifies Gramaglia. "In the short term, what it is saved on the licences is spent in the formation of the staff, that will have to learn to use the new instruments. There are 9500 employees, nowadays, that use the computers ".
    Surely, for Microsoft, the perspective of losing the returns of the licences in an apparatus of these dimensions does not have to be pleasant. Someone is complaining? "Absolutely not", the city council member answers. "Those of Microsoft know the esteem that we have for them. As an example, they are the sponsors of a communal program for the computer science schooling of the elderly. And they will continue to collaborate with us on other plans ".
    (26 February 2004)