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Security

Entropy Problems For Linux In the Cloud 179

CalTrumpet writes "Our research group recently spoke at Black Hat USA on the topic of cloud computing security. One of the interesting outcomes of our research was the discovery that the combination of virtualization technologies and public system images results in a problem for random number generation on guest operating systems. This is especially true for Linux, since its PRNG uses only a small set of entropy-gathering events, and virtual Linux images often generate SSH host keys within seconds of their initial boot. The slides are available; the PRNG vulnerability material begins at slide 63."
United States

The Chemistry of Firework Displays 65

Ponca City, We love you writes "David Ropeik writes at MSNBC that there's a lot more to making a basic firework display than putting a fuel source and an oxidizer together. Pyrotechnic chemists, who are trying to create bedazzlement instead of bang, don't want their work to explode, but to burn for a bit, so it gives a good visual show. To achieve the desired effect, the sizes of the particles of each ingredient have to be just right, and the ingredients have to be blended together just right. To slow down the burning, chemists use big grains of chemicals, in the range of 250 to 300 microns, and they don't blend the ingredients together very well, making it harder for the fuel and oxidizer to combine and burn, thus producing a longer and brighter effect. Surprisingly few emitters are used in pyrotechnics, and there are no commercially useful emitters in blue-green to emerald green in the 490-520 nm region. Energy from the fire in the basic fuel is transferred to the atoms of the colorant chemicals, exciting the electrons in those chemicals into a higher energy state. As they cool down, they move back to a lower state of energy, emitting light. So, you actually see the colors in fireworks as they're cooling down. To get the really tricky shapes, like stars or hearts, the colorant pellets are pasted on a piece of paper in the desired pattern. That paper is put in the middle of the shell with explosive charges above it, and below. When those charges go off, they burn up the paper, and send the ignited colorant pellets out in the same pattern they were in on the sheet of paper, spreading wider apart as they fly."

Comment Re:navigation maps (Score 1) 265

This may surprise you, but the problem of updating charts has been encountered before. And solved. In the early nineteenth century by Admiral Beaufort. The Hydrographic Office issues weekly 'Notices to Mariners' which list the changes to be made to charts. These include shifting sandbanks, new navigational bouys, new survey data and yes, new wind turbines. As far as navigation is concerned it's not a new island it's a new wind turbine. If the captain was unsure of his position the sight of one (and it would be visible at some distance) would give a clue as to his position.

Comment Re:Speed limiters already on HGVs / trucks? (Score 1) 859

Yes they do. Travelling on motorways in the cab of an HGV at 56mph is a surreal experience. Everything happens very slowly. If an empty, powerful truck finds itself behind a weak, full truck going up hill it'll still overtake so 2 of the 3 motorway lanes become slow lanes. You do find them overtaking each other on the flat, usually because one limiter is set slightly higher than another.

Programming

Worst Working Conditions You Had To Write Code In? 1127

sausaw writes "I recently had to write code in a hot dusty room for 20 days with temperatures near 107F (~41C); having nothing to sit on; a 64 Kbps inconsistent internet connection; warm water for drinking and a lot of distractions and interruptions. I am sure many people have been in similar situations and would like to know your experiences."
Networking

Grad Student Project Uses Wikis To Stash Data, Miffs Admins 268

Anonymous writes "Two graduate students at the Ivy League's Brown University built a P2P system to use abandoned wiki sites to store data. The students were stealing bandwidth from open MediaWiki sites to send data between users as an alternative to BitTorrent. There was immediate backlash as site operators quickly complained to the University. The project appears to be shutdown, but many of the pages still remain on the web. The project homepage was also taken down and the students posted an apology this afternoon." The same submitter links to two different forum discussions on the project.
Google

Google To Monitor Surfing Habits For Ad-Serving 219

superglaze (ZDNet UK) writes "Google is gearing up to launch cookie-based 'interest-based' advertising, which involves monitoring the user's passage across various WebSense partner sites. The idea is to have better-targeted advertising, which is not a million miles away from what Phorm is trying to do — the difference, it seems at first glance, is that Google is being relatively up-front about its intentions."
Communications

Presidential Inauguration Hardware and Other Challenges 176

holy_calamity writes "The FBI has released images of some of the kit that will be deployed to safeguard Obama's inauguration, including mine-proof armored trucks like those used in Iraq to protect against IEDs, and a large armored chamber that any bombs will be shoved inside to be transported away and perhaps detonated inside. Interesting, even though the really good stuff is presumably being kept under wraps." Relatedly, necro81 writes "The Inauguration of Barack Obama tomorrow is expected to put considerable stress on the cellphone network around Washington, DC. The expected crowd could top two million people, and many of them are expected to call, text, tweet, photo, and blog their way through the event. In response, the major wireless carriers in the area have spent millions of dollars upgrading their local networks and will bring in extra 'cells on wheels' (COWs) and 'cells on light trucks' (COLTs). They are also requesting that attendees limit their usage during the event, and avoid bandwidth-heavy activities — like uploading photos — until afterward."
Businesses

How Does a 9/80 Work Schedule Work Out? 1055

cellocgw writes "My company is in the process of implementing a version of '9/80,' a work schedule that squeezes 80 hours' labor time into 9 business days and provides every other Friday off. I was wondering how this has been implemented in other companies, and how it's worked out for other Slashdot readers. Is your system flexible? Do you find time to get personal stuff done during the week? Is Friday good for anything other than catching up on lost sleep? And perhaps most important, do your managers respect the off-Fridays, or do they pull people in on a regular basis to handle 'crises?'"
Robotics

A Robotic Bartender, and How To Build One 66

Jamie Price writes with a nice tutorial on putting technology to use in the service of mankind, with one of his latest projects — BaR2D2. "BaR2D2 is a radio-controlled, mobile bar that features a motorized beer elevator, motorized ice/mixer drawer, six-bottle shot dispenser, and sound activated neon lighting. The robot is driveable so you can take the party on the road! It was created in my garage using standard hand/power tools and readily available parts and materials. Here is a video of it in action. To see the full how-to with tons of pictures, check out the build.
Supercomputing

Roland Piquepaille Dies 288

overheardinpdx writes "I'm sad to report that longtime HPC technology pundit Roland Piquepaille (rpiquepa) died this past Tuesday. Many of you may know of him through his blog, his submissions to Slashdot, and his many years of software visualization work at SGI and Cray Research. I worked with Roland 20 years ago at Cray, where we both wrote tech stories for the company newsletter. With his focus on how new technologies modify our way of life, Roland was really doing Slashdot-type reporting before there was a World Wide Web. Rest in peace, Roland. You will be missed." The notice of Roland's passing was posted on the Cray Research alumni group on Linked-In by Matthias Fouquet-Lapar. There will be a ceremony on Monday Jan. 12, at 10:30 am Paris time, at Père Lachaise.
Transportation

Amtrak Photo Contestant Arrested By Amtrak Police 675

Photographer Duane Kerzic was standing on the public platform in New York's Penn Station, taking pictures of trains in hopes of winning the annual photo contest that Amtrak had been running since 2003. Amtrak police arrested him for refusing to delete the photos when asked, though they later charged him with trespassing. "Obviously, there is a lack of communication between Amtrak's marketing department, which promotes the annual contest, called Picture Our Trains, and its police department, which has a history of harassing photographers for photographing these same trains. Not much different than the JetBlue incident from earlier this year where JetBlue flight attendants had a woman arrested for refusing to delete a video she filmed in flight while the JetBlue marketing department hosted a contest encouraging passengers to take photos in flight." Kerzic's blog has an account of the arrest on Dec. 21 and the aftermath.
Power

Home Generators (or How DTE Energy Ruined My Holidays) 695

We are among the thousands without power in the northeast. Day four actually, and we've decided to look into generators so that next year's New Year's doesn't involve fears of frozen pipes bursting and hypothermic babies and cats. At the very least we just need enough juice to run the furnace blower, but if we're going to lay down the cash I'd like to know what it would take to get a little more power ... like enough to run a fridge, router, laptop and lightbulb. I know nothing about this sort of thing, but figure there are more than a few experts out there so I call out to the wisdom of the mob. What am I looking for? How difficult is the wiring? What will it cost me? On the extreme edge, what would it take to get off the grid entirely? (And on a side note, thanks to DTE Energy for telling us we had power when we didn't, for losing the ticket for our neighborhood, for telling us it would be back every single day when it wasn't, and for the helpful DTE representative who warned us that our pipes might burst. Thanks.)

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