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NASA To Cryogenically Freeze Satellite Mirrors 47

coondoggie writes "NASA said it will soon move some of the larger (46 lb) mirror segments of its future James Webb Space Telescope into a cryogenic test facility that will freeze the mirrors to -414 degrees Fahrenheit (~25 K). Specifically, NASA will freeze six of the 18 Webb telescope mirror segments at the X-ray and Cryogenic Facility, or XRCF, at NASA's Marshall Space Flight Center in Huntsville, Alabama, in a test to ensure the critical mirrors can withstand the extreme space environments. All 18 segments will eventually be tested at the site. The test chamber takes approximately five days to cool a mirror segment to cryogenic temperatures."
Classic Games (Games)

M.U.L.E. Is Back 110

jmp_nyc writes "The developers at Turborilla have remade the 1983 classic game M.U.L.E. The game is free, and has slightly updated graphics, but more or less the same gameplay as the original version. As with the original game, up to four players can play against each other (or fewer than four with AI players taking the other spots). Unlike the original version, the four players can play against each other online. For those of you not familiar with M.U.L.E., it was one of the earliest economic simulation games, revolving around the colonization of the fictitious planet Irata (Atari spelled backwards). I have fond memories of spending what seemed like days at a time playing the game, as it's quite addictive, with the gameplay seeming simpler than it turns out to be. I'm sure I'm not the only Slashdotter who had a nasty M.U.L.E. addiction back in the day and would like a dose of nostalgia every now and then."

Network Neutrality Back In Congress For 3rd Time 248

suraj.sun writes "Ed Markey has introduced his plan to legislate network neutrality into a third consecutive Congress, and he has a message for ISPs: upgrade your infrastructure and don't even think about blocking or degrading traffic. The war over network neutrality has been fought in the last two Congresses, and last week's introduction of the 'Internet Freedom Preservation Act of 2009' [PDF] means that legislators will duke it out a third time. Should the bill pass, Internet service providers will not be able to 'block, interfere with, discriminate against, impair, or degrade' access to any lawful content from any lawful application or device. Rulemaking and enforcement of network neutrality would be given to the Federal Communications Commission, which would also be given the unenviable job of hashing out what constitutes 'reasonable network management' — something explicitly allowed by the bill. Neutrality would also not apply to the access and transfer of unlawful information, including 'theft of content,' so a mythical deep packet inspection device that could block illegal P2P transfers with 100 percent accuracy would still be allowed. If enacted, the bill would allow any US Internet user to file a neutrality complaint with the FCC and receive a ruling within 90 days."

Submission + - Potential database breakthrough

DuckDodgers writes: "The database company Ingres announced a partnership with research firm Vectorwise to bring to market an efficiency breakthrough in databases. They assert that most complex queries run by a database engine can run over 100 times slower than a C++ program hand coded to get the same information from the files on disk. They're working on a database engine that closes the gap dramatically by using several methods, like batching tuples for processing in sizes that fit in the processor on-chip cache, other methods for minimizing back and forth between RAM and processor cache, and structuring the data to be processed in a way to make best use of CPU branch prediction. Their example in the whitepaper (unfortunately, it requires registration) is a moderate complexity aggregate query against 6 million rows of data that takes 16 seconds in the regular database engine, 0.04 seconds with a C++ application built to do the same thing, and about 0.2 seconds with their optimized database engine. The press release is here, and some of the technical details are discussed on this blog (no, not mine): Next Big Future. Is this impossible, impractical, or well within the realm of possibility? If it can be done, why haven't we seen it before?"

Submission + - Cray's Comeback and the Future of Supercomputing

Greg Huang writes: "In the 1970s and 80s, Cray was synonymous with supercomputing. But the company fell on hard times after getting bought by Silicon Graphics in 1996 and then merging with Tera Computer in 2000. What has happened to Cray since then? Xconomy has an in-depth profile of the "new Cray" as it makes its way back to the top of the supercomputing world, including its strategy for gaining customers and advancing its technology in the perpetual race to build the world's fastest, most powerful machine."

Submission + - Why do we have F2XM1? (blogspot.com)

QuietObserver writes: I was researching the Intel Floating Point instructions while working on a project, and I first came across F2XM1. I immediately wondered what the need was for an instruction that does 2 ^ x — 1 but has an input range of -1 to 1. I've tried researching the subject online, but all I've come up with is a reference from someone else who has the exact same question.

Quoted from http://jheriko-rtw.blogspot.com/2009/04/why-do-we-have-f2xm1.html?showComment=1249084660633#c6336764748095052620

F2XM1 is a floating point assembler instruction for Intel CPUs. It is one of several which seem to be there to allow the calculation of several of the common "higher" functions, like pow(x, y) or log(x). However, I am always confused why it subtracts one after finding the power of 2 and why its limited from -1 to 1, since it doesn't seem to help anything much at all...

If anyone has any comments or suggestions about what use F2XM1 might have, and why Intel's FPU architecture also lacks an instruction to perform 2^x without subtracting anything (I know of at least one other FPU instruction set that does, and has no input range limitations).

The Internet

Submission + - OpenBitTorrent, a DMCA-Resistant Torrent Tracker (openbittorrent.com)

rm writes: "There seemed to be no open, independent and stable BitTorrent trackers out there, so some hackers decided to create OpenBitTorrent, a free for anyone to use and (supposedly) a stable tracker. As a nice bonus, since the new tracker does not know or care what it is tracking, it is very likely to be completely immune to DMCA takedown requests: the authors make it very clear that they do not host or index for searching the content or any torrent files, do not keep logs of downloaders' IP addresses and can not block any files from being distributed using their tracker. Also, it looks like ThePirateBay has recently started to use OpenBitTorrent as a secondary tracker for all its torrents."

Comment Re:Correctly? (Score 1) 895

How is teleporting people in front of NPC bots designed to enforce a safe zone instead of beating someone up yourself "playing correctly?"

It is since the zone is not flagged as "non-teleport", like we used to do with '80s technology in MUDs. The guy is playing by the rules and he's on infringing the EULA/whatever they have (else he would have been banned).


Artist Wins £20,000 Grant To Study Women's Butts 202

Sue Williams has been awarded a £20,000 grant by the Arts Council of Wales, to "explore cultural attitudes towards female buttocks." Sue plans to examine racial attitudes towards bottoms in Europe and Africa and create plaster casts of women's behinds to try to understand their place in contemporary culture. And here I've been studying the issue all these years for free like a sucker!

Submission + - New attempt at Internet censorship in Italy (ilcannocchiale.it) 3

myrrdyn writes: There is a new law proposed in Italian Senate to block online publication of information about past criminal trials. Main point of this proposal (link in Italian) is to ensure an "oblivion right" to those condemned for past crimes/misdemeanor, i.e. the right to have publication about past offenses removed from public view. What is troubling about this is that in current form (yet to be discussed) no exemption are contemplated, except for terrorism, life sentences and such. Under the hood of privacy concern there is a serious attempt to limit liberty of speech and liberty of press. Is not a small coincidence that the proposer (On. Carolina Lussana) has an husband (Mr. Galati, elected in the Deputy Chamber) who was condemned some years ago in criminal trials, and the two together are in the coalition lead by Silvio Berlusconi, who also faced (and is facing) trials related to judge corruptions and much more
Data Storage

Graphene Could Make Magnetic Memory 1000x Denser 123

KentuckyFC writes "The density of magnetic memory depends on the size of the magnetic domains used to store bits. The current state-of-the-art uses cobalt-based grains some 8nm across, each containing about 50,000 atoms. Materials scientists think they can shrink the grains to 15,000 atoms but any smaller than that and the crystal structure of the grains is lost. That's a problem because the cobalt has to be arranged in a hexagonal close packing structure to ensure the stability of its magnetic field. Otherwise the field can spontaneously reverse and the data is lost. Now a group of German physicists say they can trick a pair of cobalt atoms into thinking they are in a hexagonal close packing structure by bonding them to a hexagonal carbon ring such as graphene or benzene. That's handy because the magnetic field associated with cobalt dimers is calculated to be far more stable than the field in a cobalt grain. And graphene and benzene rings are only 0.5 nm across, a size that could allow an increase in memory density of three orders of magnitude."

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