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Crime

UK Politician Arrested Over Twitter 'Stoning Joke' 422

History's Coming To writes "The BBC is reporting that a Tory city councillor has been arrested over a 'joke' he posted to Twitter suggesting that Yasmin Alibhai-Brown, a UK based writer, be stoned to death. The full tweet read, 'Can someone please stone Yasmin Alibhai-Brown to death? I shan't tell Amnesty if you don't. It would be a blessing, really.' Following complaints he was arrested under the Communications Act 2003 and bailed. He has since apologized. This comes on the same day that a conviction for a Twitter 'joke' about blowing up an airport was upheld."
Power

Going Faster Than the Wind In a Wind-Powered Cart 315

Shawnconna writes "Can a wind cart travel faster than the wind? A group of makers say, 'Yes!' Make: Online has published a story about the Blackbird wind cart that just set a record. This is a follow-up to an earlier story in which Charles Platt built a cart based on a viral video where a guy claimed he'd built a wind-powered vehicle that could travel downwind faster than the windspeed. Charles built one and said it didn't work. Heated debates broke out in forums, on BB, and elsewhere on the Net. In the ensuing time, a number of people have built carts and claimed success, most principally, Rick Cavallaro. He got funding from Google and JOBY to build and test a human-piloted cart. They claim success, with multiple sensor systems on board, impartial judges and experts in attendance."

Comment Re:Just to throw this out there (Score 1) 322

You know, I just shouldn't have chimed in. I'm beginning to regret that I did.

Thank you for speaking down to me. Now, lets get to business.

I get it. I actually understand computational complexity very well. Had you read the follow-up post, which was posted well before your post, you would see that I added the caveat "if P!=NP", long before you had a chance to talk down to me.

Comment Re:Just to throw this out there (Score 1, Interesting) 322

I should caveat all of this. The "no polynomial-time algorithm" bit is only true if P!=NP. If P=NP, then there is a deterministic polynomial-time algorithm for NP-Complete problems. NP-Hard, however, just means that it's at least as hard as NP, so, it's possible that there's no algorithm for that harder problem. You have to be really really precise when talking about this stuff.

Comment Just to throw this out there (Score 5, Informative) 322

Since I had to suffer through at least one professor who didn't understand basic complexity theory last night, and I know that Slashdot generally screws it up to.

NP-Hard means that there's no (deterministic) polynomial-time algorithm to solve the games. Additionally, you always have to generalize these games in order to make that claim. Since computational complexity is defined in terms of the length of the input, and certainly all of these games are being played on an input of fixed length.

However, there are effective approaches to solving NP-Hard problems. There are solvers for known NP-Hard problems. If you Google "sat solver" you'll find at least 5 that you can just download. SAT solvers are used in VLSI validation and other practical things. These solvers use heuristics to improve search performance, generally proposing answers and checking them (for NP-Complete problems).

Also, there are tons of games known to be NP or PSPACE complete. The reductions for those games are kind of a standard problem, since the AI community writes a bunch of these solvers.

Transportation

White House Issues New Gas Mileage Standards 555

Hugh Pickens writes "NPR reports that the Obama administration has signed off on the nation's first rules on greenhouse gas emissions and set new fuel standards to meet a fleet-wide average of 35.5 mpg that will raise current standards by nearly 10 mpg by the 2016 model year. Although the new requirements would add an estimated $434 per vehicle in the 2012 model year and $926 per vehicle by 2016, drivers could save as much as $3,000 over the life of a vehicle through better gas mileage, according to a government statement. 'We will be helping American motorists save money at the pump, while putting less pollution in the air,' says Transportation Secretary Ray LaHood. Dave McCurdy, leader of the Alliance of Automobile Manufacturers, a trade group representing 11 automakers, says the industry supports a single national standard for future vehicles. 'Today, the federal government has laid out a course of action through 2016, and now we need to work on 2017 and beyond.' As the auto industry seeks to emerge from ashes, many manufacturers already are trying for the right mix of approaches, experts say. Some will try to sell more hybrids. Others are introducing not-so-gas-guzzling SUVs. They may also push slightly downsized and small cars, such as the Ford Fiesta."
Open Source

Submission + - Where to donate Power Mac G5s? 3

vm writes: I work for a medium sized software developer that publishes products for both OS X and Windows. Since we've been a Mac dev for the past 12 years, we often end up with a deluge of old hardware after a few years of constantly purchasing the latest systems to develop and QA check our products. Recently, we've consolidated about a dozen Power Mac G5 systems and I thought we should try to find a home for them aside from our local PC recycling non-profit. Don't get me wrong — our local non-profit does great work and sells a lot of Linux systems to support their cause. But I took a quick look around and only found a couple of open source projects that are asking for hardware donations at this time. One, CRUX PPC, is in Italy so it would be cost prohibitive to send them one or more systems. Since we can't include hard drives, operating systems, or software, most schools in the area aren't willing to take them. Has anyone else come across this problem and how did you go about solving it?

Submission + - SPAM: How to Throw a Knockout Punch

patojag writes: A knockout punch can end all contests decisively. It can finish fights without dispute and can save your life in grave circumstances. But before we get into the details on what makes a knockout punch, we must first understand the anatomy of the knockout.
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