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Submission + - Questionable Patents From MakerBot ( 1

An anonymous reader writes: OpenBeam USA is a Kickstarted company that builds open source aluminum construction systems (think erector sets). One of the main uses for the system is building 3D printers, and creator Terence Tam is heavily involved in the 3D-printing community. He's now put up a blog post about some disturbing patents filed by MakerBot. In particular, he notes a patent for auto-levelling on a 3D printer. Not only is this an important upcoming technology for 3D printers, the restriction of which would be a huge blow to progress, it seems the patent was filed just a few short weeks after Steve Graber posted a video demonstrating such auto-levelling. There had also been a Kickstarter campaign for similar tech a few months earlier. Tam gives this warning: 'Considering the Stratasys — Afinia lawsuit, and the fact that Makerbot is now a subsidiary of Stratasys, it's not a stretch to imagine Makerbot coming after other open source 3D manufacturers that threaten their sales. After all, nobody acquires a patent warchest just to invite their competitors to sit around the campfire to sing Kumbaya. It is therefore vitally important that community developed improvements do not fall under Makerbot's (or any other company's) patent portfolio to be used at a later date to clobber the little guys.'

Comment Re:Just downloaded it... (Score 1) 148

...For that matter I assume it isn't taking into account acceleration (note to physicists: does non-gravity acceleration cause time dilation?).

Still it is free, and makes me feel very very very slightly younger!

IAAP (I am a physicist), so I can confirm that non-gravitational acceleration causes time dilation, under some circumstances. Since I'm waiting for some calculations to finish running through Mathematica, I'll also try to explain. :-)

Non-gravitational acceleration does cause time dilation, at least when viewed in the frame of the accelerated observer. When analyzed in the frame of an inertial observer (read: if someone who isn't accelerating calculates how much time has passed for you based on how you are moving), these effects appear to be the result of your velocity, and *not* your acceleration.

A fun example of this is the Langevin twin paradox problem. Two twins, floating in space, synchronize their watches. Then twin A uses a rocket to travel out a certain distance d at a more or less constant velocity v, turn around, and return, also with velocity v. He only uses his rocket for a very brief period upon leaving, during turnaround, and finally to return to rest relative to his twin. Twin B just sits there. They then compare their clocks.

Twin B sees that twin A spent essentially all of his time moving with velocity v, and figures that time-dilation has caused twin A's clock to record less time than twin B's. This is correct.

From twin A's perspective, it was twin B who moved with velocity v, and so he figures that time-dilation has caused B's clock to record less time than A's. This seems paradoxical until twin A accounts for the fact that he was accelerated at the far end of his trip. During that acceleration, everything not attached to his rocket (including twin B) seemed to accelerate in the direction his engine was pointed. There's a bunch of math one can do to justify it, (see chapter 13 of Misner, Thorne, and Wheeler's "Gravitation", if you want the full scoop) but the short version is that acceleration acts just like gravity (and vice versa). So twin A figures that twin B's clock must be gravitationally blueshifted relative to twin A's clock (twin B is 'higher' in the apparent gravitational potential produced by the acceleration). It turns out that over the amount of time twin A must accelerate to return to his twin, twin B's clock seems to gain exactly twice as much time as he seems to lose while twin A is coasting, which is just enough to bring each of the twins' calculations into full agreement upon their reunion.

Relativity is fun. :-)

Submission + - Windows 7 update installs stealth WAT 7

unassimilatible writes: A Windows 7 update released on 9/30, KB2158563, claims to "resolve issues caused by revised daylight saving time and time zone laws in several countries. This update enables your computer to automatically adjust the computer clock on the correct date in 2010." The part not mentioned by Microsoft is that KB2158563 is a Trojan, the stealth payload being a WAT (Windows Activation Technologies) update that sniffs out cracked versions of Windows 7, and declares them not genuine, complete with black screen. Looks like MS is up to its old tricks again.

Submission + - Government Randomly X-Raying Citizens (

shahidg writes: You might want to think twice about going out the door from now on. Homeland Security is apparently now performing random x-rays on highways, border crossings and even city streets. The public can only hope that these random and uncontrolled doses of radiation being unknowingly administered on them will not cause any serious health effects.
United Kingdom

Submission + - SPAM: UK Set to Add Legal Sovereignty Clause in EU Bill

maars_news writes: UK Foreign Secretary William Hague has reportedly promised a âÅ"sovereignty clauseâ that will be added to a European Union bill, which will be introduced in Britain later this year.
He told Tory MPs about the billââs introduction this autumn and that it would make clear that EU directives take effect in the UK only by the will of Parliament, which can be withdrawn, the BBC reported.
  The idea was first brought up by David Cameron last year when he said that, without a written constitution, there was a danger that over a period of time, UK courts might âÅ"come to regard ultimate authority as resting with the EUâÂ.
However, the Conservatives argue that the floating of this âÅ"UK Sovereignty Billâ would ultimately put Britain on par with other European states like Germany. They further criticize with no written constitution in Britain at present, has no explicit legal guarantee that the last word on British laws stays in the country itself.

Link to Original Source

Govt To Bomb Guam With Frozen Mice To Kill Snakes 229

rhettb writes "In a spectacularly creative effort to rid Guam of the brown tree snake, an invasive species which has ravaged local wildlife and angered local residents, the US Department of Agriculture is planning to 'bomb' the island's rainforests with dead frozen mice laced with acetaminophen. While it might not seem difficult to purge an island of snakes, the snake's habit of dwelling high in the rainforest canopy has so far thwarted efforts to rid the island of the pest. Eradicating the snake is a priority because it triggers more than 100 power outages a year at a cost of $1-4 million and has driven at least 6 local bird species to extinction."

What Happens To a Football Player's Neurons? 176

An anonymous reader writes "It seems like every week there's a new story about the consequences of all those concussions experienced by football players and other athletes — just a few days ago, the NY Times reported that some athletes diagnosed with Lou Gehrig's Disease may actually have a neural disease brought on by head trauma. But missing in these stories is an explanation of what head trauma actually does to the brain cells. Now Carl Zimmer has filled in the gap with a column that takes a look at how neurons respond to stress, and explains how stretching a neuron's axon turns its internal structure into 'mush.'"

Comment Re:20 years?! (stupid gimmick) (Score 1) 319

I doubt that much of that 700 lbs would *not* be riddled with rust long before that lease would run out.

If you RTA you'll see that the bodywork is made from carbon composite. I don't think it's that unreallistic for a car to still be going after 20 years - how many cars are there around on the roads from 1989/1990? Still quite a few (esp. Japanese made), in some parts of the world the majority of cars are that old or older.

And every one of those cars has a couple of dings and dents in them. Dings and dents that become gaping holes in carbon fiber bodies. gaping holes that drastically degrade the vehicle's aerodynamics, which in turn have an outsize impact on the vehicle's fuel efficiency. While it's true that there are plenty of cars that are still going after 20 years, none of those cars are the lead models of an entirely new and untested design.

But this post is a great illustration of how many people view cars as throwaway, disposable products, good for only 10 years. Cars don't just impact the environment with CO2 emissions, the material and energy cost of production, maintenance and disposal have to be taken into account, and it's about time seeing a manufacturer taking responsibility in this regard, rather than cashing in on the easy profits of throwaway consumerism

Nice try for putting words in my mouth. My concern is whether the damn thing will still be running in 20 years, or whether the company which is supposedly paying for all your fuel will be around for 20 years to make good on its side of the bargain. If I had any reason to be confident in both of those points, I'd be all for purchasing this kind of rollerskate (provided that the price made sense, of course). Based on the cursory descriptions presently available, which do not address these issues at all, I tend to the conclusion that this whole thing is more PR fluff than substance.

Comment Re:20 years?! (stupid gimmick) (Score 2, Insightful) 319

A 20 year lease sounds like a dumb gimmick.

But you could drive the car in a climate that gets snow and salted roads - the body is carbon fiber - no rust!

Not everything can be made of carbon fiber. The metal parts (engine, exhaust system, etc) will still rust. Plus, 20 years is a very long time to commit to a car. Lots of expensive components tend to wear out over such a long period. We're supposed to believe that the company (which has zero track record building, selling, and maintaining cars) is even going to be here after that amount of time?

Of course, based on the fine article, it rapidly becomes clear that this is a vaporware economic model for a vaporware car design. This isn't a plan for designing and building a car --it's a plan for getting media attention for the design firm. As such, it's been successful.

Comment 20 years?! (stupid gimmick) (Score 4, Insightful) 319

Well I guess that means they aren't planning on marketing this in the Northeast, or anywhere that there's occasionally snow on the ground. I doubt that much of that 700 lbs would *not* be riddled with rust long before that lease would run out. Seriously, why lease a car for 20 years? And what'd the lease payment be? Not to mention the fact that you could probably just buy the damn thing (or maybe even a nicer car) using a 20 year car loan and cover the fuel out of pocket for far less than what you'd pay these jokers. Effectively locking in the cost of fuel for 20 years may sound attractive, but in practice it's more likely a win-win for the company --sure, you don't pay extra when fuel prices go up, but you also miss out on the downward fuel price fluctuations. The company is certain to make more money from you than you'll get out in fuel in any case, since if the prices are such that the deal would seem to work out in your favor, the company will just go bankrupt.

Chrome EULA Reserves the Right To Filter Your Web 171

An anonymous reader writes "Recently, I decided to try out Google Chrome. With my usual mistrust of Google, I decided to carefully read the EULA before installing the software. I paused when I stumbled upon this section: '7.3 Google reserves the right (but shall have no obligation) to pre-screen, review, flag, filter, modify, refuse or remove any or all Content from any Service. For some of the Services, Google may provide tools to filter out explicit sexual content. These tools include the SafeSearch preference settings (see In addition, there are commercially available services and software to limit access to material that you may find objectionable.' Does this mean that Google reserves the right to filter my web browsing experience in Chrome (without my consent to boot)? Is this a carry-over from the EULAs of Google's other services (gmail, blogger etc), or is this something more significant? One would think that after the previous EULA affair with Chrome, Google would try to sound a little less draconian." Update: 04/05 21:14 GMT by T : Google's Gabriel Stricker alerted me to an informative followup: "We saw your Slashdot post and published the following clarification on the Google Chrome blog."

Battlestar Galactica Comes To an End 852

On Friday evening, Battlestar Galactica ended its four-season run as one of the most popular science fiction shows in recent history. 2.4 million people tuned in for the finale, and reactions to the ending — positive, negative, and often a mix of both — are springing up all over the internet, as are tributes and retrospectives. Producers Ron Moore and David Eick held a Q&A session after the finale to discuss certain aspects of the story and spell out the final status of several plot lines. Fans of the show will have a chance to see the Cylon side of the story this fall in a two-hour TV movie titled "The Plan," and we've previously discussed the spin-off prequel series, Caprica, the pilot for which will come out on April 21st. Be warned: these links and the following discussion will contain spoilers.

Comment Re:Oh Really? (Score 3, Insightful) 336

Pretty soon, people will get used to a bright flash between the previews and the start of the film. Add to that an infrared video camera, and they can keep track of people changing seats during the movie.

Of course, the natural response of the wittier bootleggers will be to wear a Guy Fawkes mask to the theater. :-)

Comment Risky to Deploy (Score 1) 332

Such a system seems quite dangerous to deploy, since it would inevitably be assumed to be targeting nuclear launch sites (no difference between an ICBM and an anti-sat rocket). Because of its speed to target, an opponent would have no choice but to launch immediately if he saw the slightest hint that you were *preparing* to deploy these puppies.

Microsoft Deprecating Some OOXML Functionality 138

christian.einfeldt writes "According to open standards advocate Russell Ossendryver, Microsoft will be deprecating certain functionality in its Microsoft Office Open XML specification. Ossendryver says the move is an attempt to quiet critics of the specification in the run up to the crucial February ISO vote. The Microsoft-led industry standards group formally offering OOXML confirms in a 21 December 2007 announcement that issues related to the 'leap year bug', VML, compatibility settings such as 'AutoSpaceLikeWord95' and others will be 'extracted from the main specification and relocated to an independent annex in DIS 29500 for deprecated functionality.'"

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