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Submission + - Move over, quantum cryptography: Classical physics can be unbreakable too (extremetech.com)

MrSeb writes: "Quantum cryptography? Pah! That’s for newbies, according to researchers from Texas A&M University who claim to have pioneered unbreakable cryptography based on the laws of thermodynamics; classical physics, rather than quantum. In theory, quantum crypto (based on the laws of quantum mechanics) can guarantee the complete secrecy of transmitted messages: To spy upon a quantum-encrypted message would irrevocably change the content of the message, thus making the messages unbreakable. In practice, though, while the communication of the quantum-encrypted messages is secure, the machines on either end of the link can never be guaranteed to be flawless. According to Laszlo Kish and his team from Texas A&M, however, there is a way to build a completely secure end-to-end system — but instead of using quantum mechanics, you have to use classical physics: the second law of thermodynamics, to be exact. Kish’s system is made up of a wire (the communication channel), and two resistors on each end (one representing binary 0, the other binary 1). Attached to the wire is a power source that has been treated with Johnson-Nyquist noise (thermal noise). Johnson noise is often the basis for creating random numbers with computer hardware. For details of how the system works, read the article."

Comment More like grilling for the gadget-obsessed (Score 5, Informative) 169

Personally, I think most of these gadgets are worthless. Yes, a thermometer is useful (but I prefer the instant-read kind like the Thermapen for quick checks in multiple locations). Otherwise, you really only need a good pair of extra-long tongs (that 3-in-1 thing in TFA looks clunky as heck) and a spatula.

If you really want to grill like a geek, check out Kenji Alt's Food Lab posts over on Serious Eats. He's got a nice guide up right now on how to grill a steak the right way (complete with explanations based on food science and his own experiments), and he's been doing a series on the best inexpensive steaks (at least, inexpensive compared to porterhouse and tenderloin).


Submission + - Spider Silk Spun Into Violin Strings

jones_supa writes: A Japanese researcher wanted to try how spider silk would convert to strings of a violin. Dr. Shigeyoshi Osaki of Nara Medical University used 300 female Nephila maculata spiders to provide the dragline silk. For each string, Osaki twisted thousands individual strands of silk in one direction to form a bundle. The strings were then prepared from three of these bundles twisted together in the opposite direction. The final product withstood less tension before breaking than a traditional gut string, but more than an aluminum-coated, nylon-core string. This kind of spider-strings are described to have a 'soft and profound timbre'.

Submission + - W Boson mass found, leads way to Higgs Boson (sciencedaily.com)

SchrodingerZ writes: Scientists have deduced the “world's most precise measurement of the mass of the W Boson,one of nature's elementary particles, has been achieved by scientists from the CDF and DZero collaborations at the Department of Energy's Fermi National Accelerator Laboratory.” This new number (80375 +-23 MeV/c2 by the way) puts more constraint on the mass of the theorized http://www.exploratorium.edu/origins/cern/ideas/higgs.html"> Higgs Boson Particle ,which is theorized to give mass to all other things, completing the http://public.web.cern.ch/public/en/Science/StandardModel-en.html"> standard model .“Scientists employ two techniques to find the hiding place of the Higgs particle: the direct production of Higgs particles and precision measurements of other particles and forces that could be influenced by the existence of a Higgs particle.”

Submission + - Senator Al Franken Loves Math (nctm.org)

The Stranger writes: It looks like Al Franken is a fellow math geek. J. Michael Shaughnessy, the current president of the National Council of Teachers of Mathematics, was invited to attend one of Senator Franken's constituent breakfast meetings by a math teacher who is spending a year on the senator's staff. He got a pleasant surprise at the end of the meeting when Franken said, "Let me show you my geometric proof of the Pythagorean theorem!" and the two men "plopped down on the hallway carpet" with scratch paper and a pen to talk about it. Shaughnessy used the episode to write about how enthusiasm about mathematics can be infectious and to speak out against how it is socially acceptable to claim to be incompetent in mathematics.

Comment Implementation, implementation, implementation (Score 4, Insightful) 349

The problem with many (maybe most?) attempts to put technology in schools and even home learning environments is that people don't think through the implementation. Technology is not magic. You cannot expect to get good results simply by dropping a chunk of technology into a classroom without spending a lot of time and energy rethinking how teaching and learning is going to work in that classroom. For example:

What, exactly, is the technology going to be used for? No hand-waving general answers allowed here (e.g., "enrich content with interactive multimedia presentations" is a useless answer).
In what specific tasks will the technology allow you to do something that would have been cumbersome or impossible without it (e.g., using graphing or numerical methods to approximate solutions to equations that are not amenable to the usual algebraic techniques)?
What more interesting or more engaging problems can you now attempt to solve (that address your learning goals) that you would not have been able to attempt without the technology?
Will you want to change or expand your set of learning goals now that you have this piece of technology? If so, how?
How much instructional time will be needed to get the teacher and students working comfortably with the technology? Is the potential benefit worth that amount of time?
How do you implement the technology in ways that do not detract from the learning you are trying to do (i.e., what are the unintended consequences)? How might you plan ahead for negative unintended uses?

Almost every case I've ever seen or read about where technology was just dropped into an educational setting without painstaking planning and thought about curriculum and implementation, not to mention extensive training of teachers and staff, resulted in mixed results at best, and failure and rejection at worst. To answer the original questions directly, technology aids can help or hinder education- it's all in the amount of time, thought, sweat and tears that get put into the implementation. I won't comment more on the home schooling part of the question, as I really have no experience there (aside from supplementing my own kids' educations).


Submission + - Timesheet management software.

An anonymous reader writes: I currently work as a help desk supervisor for the IT department of a top 30 american university. We have around 40 graduate and undergraduate students manning our support areas at different times of the day and night, and a recent augmentation of our budget has us in the position to hire more. We still do our master schedule with a moderately complex Excel file, our timesheets are submitted online using a webpage, and our workers' clock in and out with a seperate webpage which gives us reports in CSVs that we import into yet another spreadsheet. Needless to say, our current, time-consuming method is rather clunky and has us looking at alternatives.

What existing systems are out there that might fill our needs? What systems should we avoid?

Submission + - Best practices for a lossless music archive

Sparagmei writes: I'm a big music fan, and I like listening to the music I own on various pieces of digital gear. Right now my library's at about 20,000 tracks, ripped from CDs to MP3 at 256kbps (enough that I can't tell the difference on my low-end playback gear).

However, with the MP3 judgment rippling through the world, I'm interested in perhaps moving to a different compression standard. Before I do that, I'd like to ask a question: what lossless format would you recommend for making a digital "master library", which could be (relatively) easily downsampled to a compressed format? Important factors would be true losslessness, filesize (smaller than PCM WAV would be nice), embedded metadata (id3v2-like), existence of automated ripper software, and (to a lesser extent) open-source implementation of such software. Widespread playback implementation of the lossless codec is not an issue for me; the lossless library would likely be burnt to archival DVD media and stored after being downsampling with the chosen compressor.

The reason I ask is this: I've got a 20,000-track re-ripping job ahead of me. I'd like to do that just once, lossless, so that years from now, when I decide to jump from Vorbis to "komprezzor_2039_1337" or whatever, I don't need to drag out the old plastic discs. Thanks!

Submission + - Stock Market Drop Blamed on Computer Error

WebHostingGuy writes: "Today the Dow Jones Industrial Index dropped a little over 3% in value. Stock market swings come and go but it is interesting that the sudden drop in the stock market is the result of a computer glitch. According to MSNBC, the computers running were not properly calculating trades. This led to the switch to a backup system which led to several seconds delay which impacted the Dow. Even now after the close of the market spokesmen for the NYSE Group Inc. could not confirm if all closing share prices were even valid."

Submission + - Laptop hibernation a security risk?

wally writes: "I was having a long think today when it popped into my mind, is hibernation on laptops a security risk?

My flow of thought went like this: if I stole a laptop knowing that it had encrypted home and root partitions (assuming a Unix-like OS), presumably if it has a separate swap partition, that'd contain an unencrypted snapshot of the system prior to hibernation.

Therefore, this RAM image is presumably exploitable. Booting a USB stick would allow closer examination, presumably I could do anything from reading an open sensitive OpenOffice document to inserting some exploitable code into the frozen kernel to do something nasty when the laptop is next booted.

Even if the system keeps a checksum somewhere hidden to ensure the integrity of the RAM image before loading, you could at the least extract some potentially sensitive details that would otherwise be safe?

What do other slashdotters think? Is this an easily exploitable threat that should see suspended RAM images encrypted?"

Submission + - College Students Narcissistic Jerks, Study Shows

An anonymous reader writes: American higher education is plagued by vanity more than ever, CNN reports. Where do we cast blame? Why, it's the evil Internet's fault! MySpace, YouTube are among those on the chopping block, with liberal psycho-quacks calling for a parental beatdown. "A potential antidote would be more authoritative parenting." says noted hypocrite Jean Twenge. My question is, why are we blaming the internet for boosting our self-esteem?

From the Article:

"We need to stop endlessly repeating 'You're special' and having children repeat that back," said the study's lead author, Professor Jean Twenge of San Diego State University. "Kids are self-centered enough already."

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