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Comment: Re:Low-tech for a reason (Score 1) 88 88

No, I don't have to learn any of the skills, at all, and I don't want to. I don't want to spend days or hours or even minutes learning the finer points of pit BBQ, and that's the entire point of buying this robot. I don't have to learn when to turn up the heat or turn it down, I don't have to know how much wood to put in or when. I don't have to check on the condition of the product. I simply give my charge card to Williams-Sonoma, haul the BBQbot home and plug it in, add meat and wood, and get delicious brisket out the other end. Every. Single. Time. I wasted zero of my time learning how to barbeque brisket - I just enjoy the results of other people's learnings. If the robot fails, I drag it back to Williams-Sonoma and ask them to service it. It would be no different than any other tool that I own that I don't fix myself.

I don't understand your preoccupation with fear of breakdowns of systems. I know that some days, despite scheduled maintenance, my truck will breakdown in some way I can't fix and that I'll have to have to deal with a problem. Fear of the inevitable breakdown doesn't mean I sell my truck today and walk to work. It means that I understand the truck can break, and that some days I'll have to call for a tow. Similarly if the BBQbot fails in my restaurant, I tell the servers to 86 the brisket, and we sell grilled chicken until the replacement robot arrives.

As a business owner, why would I buy a BBQbot instead of hiring a pit master? Because the robot costs me $20,000, and it stays in the kitchen 24x7x365. A pit master has weekends, takes vacations, calls in sick (or doesn't call in at all), and costs me $60,000 every year. I'd be far more worried about hiring a temperamental person that could quit and cripple the menu on a busy night. And if I discovered I was that utterly dependent on the robot, I'd simply buy two of them.

Every business risks breakdowns of all kinds of complex systems every day: plumbing, fires, melted freezers, employees quitting, roof collapses, electrical problems, labor problems, yet most manage to stay in business even through disasters. Why? Because they know how to adapt to problems, and because taking the risks yields far more reward than doing nothing; instead of sitting there paralyzed by the fear that something might go wrong.

Comment: Re:Low-tech for a reason (Score 2) 88 88

Through lifelong dedication, a craftsman can align a car with a string, or smoke BBQ in a trash can, or whatever it is he or she does. But their activity doesn't scale beyond what they can personally produce. And if they end up smoking 100 pounds of meat per day to run their restaurant, that's it. There's little time left in the day to innovate. Craftsmen don't scale well, unless they industrialize their processes, (and then you risk ending up with a product with all the qualities of Budweiser.).

The rest of us are dedicated to other things: jobs, families, other hobbies. Does our inexperience mean we can't enjoy products of similar quality as the craftsmen produce? What's wrong with distilling the essence of their wisdom into a PID controller and an Atmel chip? If my BBQ-bot fails, I'm certainly not going to fix it with string - but that's not the point. The point is I could occasionally enjoy a high quality smoked brisket, thanks to a machine that knows more than I do about the process.

Comment: Re:Typical Slashdot... (Score 4, Informative) 94 94

Except for the fact that all works by U.S. Government employees in the line of duty are by default public domain, and not eligible for any copyright protection at all.

So I seriously doubt that the US Navy has an agreements with Rumblefish or any other organizations to collect royalties for their performance. It wouldn't be legal if they did.

Comment: Hold them liable (Score 3, Informative) 94 94

Reuters claimed to own Nasa's video of the 1969 Moon Landings

CD Baby claimed ownership of music by an artist sang by the artist and used with their permission.

I have frequent claims on classical music especially military marches that are clearly out of copyright and are live performances.

The organization should lose all rights to claim copyright via youtube's content id after one false claim of copyright.

Youtube should also be liable for allowing blatantly false claims once they have received notification of the copyright status of public domain works.

Comment: I don't see the logic here (Score 3, Insightful) 60 60

A launch site at latitude L can launch into an orbit of inclination L *or higher*. You can launch into a polar orbit from anywhere on the planet. You can only launch into an equatorial orbit from the equator. Equatorial sites have the advantage, not high latitude sites. (Also, the hemisphere doesn't matter. Something launched into low Earth orbit from 45 degrees south will be at 45 degrees north in about 45 minutes time.)

Some technicalities:
Yes, you can launch into one orbit then change plane to a lower inclination later - but doing so in LEO is very expensive. (I think the cheapest way to do it is to put yourself into a high eccentricity orbit, do the plane change at max distance from Earth, then recircularize your orbit into LEO.) ('expense' = delta-v.)
Launching from latitude L also can't launch into retrograde orbits closer than L to 180 degrees. E.g. from latitude +/- 30 degrees, you can launch directly into orbits with inclination between 30 and 150 degrees.
If you specifically want a 45 degree inclination orbit, I don't know whether launching due east from a 45 degree latitude is cheaper or more expensive than launching either NE or SE from an equatorial site. I suspect there is no difference.

Comment: Re:If you're using GPL code, you have no choice (Score 4, Informative) 164 164

However, the summary also mentions iOS, and I was under the impression that GPL apps on the Apple AppStore are a no go?

FWIW, the situation is a bit more nuanced than that.

If the GPL licensed code is entirely your own work, you can relicense it any way you want, including to Apple for distribution on the App Store.

Where you can get into trouble with the App Store is if you take someone else GPL'd code and release it on the App Store. This could be by including third-party GPL routines, or by publishing code that was developed by multiple parties, without their permission, where copyright has not been reassigned. This was the case for the VLC player: as the article you linked alludes, Apple took that old VLC player app out of their app store due to a copyright complaint from one of the VLC developers. That was back in 2011 -- the VideoLAN Oragniaztaion has since released their own VLC for iOS, while still retaining the GPL license (albeit in part by dual-licensing it as MPL/GPL).

Yaz (IANAL)

Comment: Re:Kids don't understand sparse arrays (Score 1) 128 128

It all depends on what you want to do with your matrices. Various operations have various costs in different sparse matrix formats. The standard ones are COO or coordinate format: a list of triples (i, j, val); DOK or dictionary of keys format: the hashmap you are thinking of; LIL or list of lists format: a list for each row and a list if pairs (j, val) in each list entry; CSR/CSC or compact sparse row/column: an array of indices where each row starts, an array of column indices and an array of values.

COO and DOK are great for changing sparsity structure; LIL is very useful if you have a lot of row-wise (or column-wise) operations, or need to manipulate rows regularly. CSR is great for matrix operations such as multiplication, addition etc. You use what suits your usecase, or change between formats (relatively cheap) as needed.

+ - Is our universe ringing like a crystal glass?->

TaleSlinger writes: Two physicists at the University of Southern Mississippi – Lawrence Mead and Harry Ringermacher – announced that our universe might not only be expanding outward from the Big Bang, but also oscillating or “ringing” at the same time. The Astronomical Journal published their paper on this topic in April.

As many know, scientists today believe our universe – all space, time and matter – began with the Big Bang some 13 billion years ago. Since then, the universe has been expanding to the size it is today. Yet, the universe as a whole has self-gravity, which tries to pull all the matter – all the stars, gas, galaxies, and mysterious dark matter – back together. This internal gravitational pull slows down the universe’s expansion. Mead said in a statement from Southern Miss:

The new finding suggests that the universe has slowed down and speeded up, not just once, but 7 times in the last 13.8 billion years, on average emulating dark matter in the process.

The ringing has been decaying and is now very small – much like striking a crystal glass and hearing it ring down.

Link to Original Source

Comment: Overpressure in upper stage oxygen tank (Score 1) 49 49

Now he says "There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause."
"That's all we can say with confidence right now. Will have more to say following a thorough fault tree analysis."
https://twitter.com/elonmusk

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