Slashdot is powered by your submissions, so send in your scoop

 


Forgot your password?
Close
typodupeerror
×

Comment Fragile Grid (Score 4, Informative) 138

by Old VMS Junkie (#29429799) Attached to: DHS To Review Report On US Power Grid Vulnerability
The electric grid has already suffered multiple cascading failures from simple events that led to widespread outage. Look into the West Coast outages of 1996 and 1998 as well as the failure in the Northeast in 2003. There's a lot of interesting science going on around networks, graph theory, complexity and all. There's a really good book on teh subject, "Six Degrees" by Watts.
Science

Mysterious Sound Waves Can Destroy Rockets 193

Posted by Soulskill from the scientists-get-the-best-toys dept.
Ponca City, We love you writes "Scientists believe that powerful and unstable sound waves, created by energy supplied by the combustion process, were the cause of rocket failures in several US and Russian rockets. They have also observed these mysterious oscillations in other propulsion and power-generating systems such as missiles and gas turbines. Now, researchers at the Georgia Institute of Technology have developed a liquid rocket engine simulator and imaging techniques to help demystify the cause of these explosive sound waves and bring scientists a little closer to being able to understand and prevent them. The team was able to clearly demonstrate that the phenomenon manifests itself in the form of spinning acoustic waves that gain destructive power as they rotate around the rocket's combustion chamber at a rate of 5,000 revolutions per second. Researchers developed a low-pressure combustor to simulate larger rocket engines then used a very-high-speed camera with fiber optic probes to observe the formation and behavior of excited spinning sound waves within the engine. 'This is a very troublesome phenomenon in rockets,' said Professor Ben Zinn. 'These spinning acoustic oscillations destroy engines without anyone fully understanding how these waves are formed. Visualizing this phenomenon brings us a step closer to understanding it.'"
Math

The Real MIT Blackjack Mastermind 195

Posted by samzenpus from the king-of-counting dept.
Wade Roush writes "21, the top movie at the box office last weekend, has everyone talking about the real identities of the MIT blackjack team members fictionalized in the movie and in the 2002 book, Bringing Down the House, on which the film is based. Last week a number of stories pointed to former MIT student and Las Vegas resident John Chang as the model for the Micky Rosa character, the club mastermind played in the movie by Kevin Spacey. But Boston-area Internet entrepreneur and real estate developer Bill Kaplan is saying that if anyone is the basis for Micky Rosa, it's him. Turns out Kaplan now battles the "e-mail churn" problem as CEO of Newton, MA, startup FreshAddress, which helps companies correct the outdated e-mail addresses in their customer databases."
Announcements

Submission + - Via Carbon Free Processor

Submitted by st_johnny
st_johnny writes: "[The]chips use less than a sixth the energy of an Intel Pentium, and less than a quarter the energy an AMD Athlon uses. In addition to efficiency, VIA has started a program called "carbon-free computing", where they offset the carbon that will be produced by the manufacturing and lifetime energy use of their CPU's. They do these offsets by building renewable power generation in developing countries, restoring forest and wetlands, and doing energy conservation." http://www.worldchanging.com/archives/006239.html http://www.via.com.tw/en/products/processors/c7-d http://www.via.com.tw/en/initiatives/cleancomputin g/carbon-free_computing.jsp
Desktops (Apple)

Submission + - Microsoft Wanted To Drop Mac Office To Hurt Apple

Submitted by Overly Critical Guy
Overly Critical Guy writes: More documents in the Iowa antitrust case have come out. This time, it's revealed that Microsoft considers Mac users its "guinea pigs" for new Office features, and they once considered dropping Mac Office entirely, "as doing so will do a great deal of harm to Apple immediately." This case has become a treasure trove of internal memos describing Microsoft's internal business practices of the last ten years.
Education

Submission + - Tech Firms Go Green As E-Waste Mounts

Submitted by yogaflame
yogaflame writes: This is where computers go to die a green death Inside Hewlett-Packard Co.'s cavernous recycling plant in the Sacramento suburbs, truckloads of obsolete PCs, servers and printers collected from consumers and businesses nationwide are cracked open by goggled workers who pull out batteries, circuit boards and other potentially hazardous components.
Businesses

Submission + - Using the Web to Get the Boss to Pay More

Submitted by
Arun Jacob
Arun Jacob writes: "The NYT has an interesting article — Using the Web to Get the Boss to Pay More — on online tools that can help in salary negotiations. Link here (Free registration required).

To summarise, the article talks about the websites that provide information on standard compensation packages for your position and role. Using this information, it should be easier to negotiate your pay with a fact-based approach rather than "feelings-based" approach. The sites profiled are —
Salary.com (Data available only for US)
Payscale.com (International)"
Security

Submission + - Will secure streams be the finite solution to DRM?

Submitted by Spiff76
Spiff76 writes: The Secustream Technologies company was one of the head news on Norwegian national TV yesterday (2007-03-02). They state that it will take months to crack their secure streaming technology, and cracking it will only reveals a few seconds of content from a specific stream. The key idea is to use lots of lots of smaller locks rather than using one big lock. More or less all DRM systems yet have been defeated and has been very cumbersome for the user. In this perspective this technology claim to use a brand new approach. Will they succeed? All software used in a non trusted computing setting is crackable. Why won't this be feasible with this technology? They have even hired DVD-Jon to try to find security holes in their technology. http://www.secustream.com/?page=technology
Data Storage

Submission + - Disk drive failures 15 times what vendors say

Submitted by
sysrammer
sysrammer writes: "Computerworld has an article on disk drive failures from the 5th USENIX Conference on File and Storage Technologies in San Jose, showing, among other things, "no evidence that Fibre Channel (FC) drives are any more reliable than less expensive but slower performing Serial ATA (SATA) drives", and that "that temperature seems to have little effect on drive reliability" (it looks like they're talking about temps closer to the upper operational limit, not catastrophic a/c failures, etc.). FTA: "About 100,000 disks are covered by this data, some for an entire lifetime of five years. The data include drives with SCSI and FC, as well as SATA interfaces. The mean time to failure (MTTF) of those drives, as specified in their datasheets, ranges from 1,000,000 to 1,500,000 hours, suggesting a nominal annual failure rate of at most 0.88%. We find that in the field, annual disk replacement rates typically exceed 1%, with 2-4% common and up to 13% observed on some systems. This suggests that field replacement is a fairly different process than one might predict based on datasheet MTTF." The authors did not identify particular vendors vs. the drive stats...their goal "is not choosing the best and the worst vendors but to help them to improve drive design and testing". Another note is that the study shows disk replacement rates, not necessarily actual failure. The article is at... http://www.computerworld.com/action/article.do?com mand=viewArticleBasic&articleId=9012066&source=NLT _AM&nlid=1 ...and the Usenix site is here... http://www.usenix.org/events/fast07/tech/schroeder .html mp"
Patents

Submission + - Patent application for Godly Powers

Submitted by
Orleron
Orleron writes: "Christopher Roller of Burnsville, MN is apparently trying to corner the market on deific abilities. He has submitted a patent application for "Godly Powers". It can be found here. In yet another example of how the US Patent system is broken, this submission actually made it through the entire process for application issuance. How much farther could it go?"

Slashdot Top Deals

Any sufficiently advanced technology is indistinguishable from a rigged demo. - Andy Finkel, computer guy

Close