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Comment Re:Write your name with a pen? (Score 1) 82

I think that's the point.

I suspect the reasoning is that one physical copy == one license. By having the physical copy tied to you, by putting your name in it, they ensure you can't pass it on to anyone else, which means the license becomes non-transferrable. That means it's safe for them to give you a digital copy of the book, covered by the same license, in the knowledge that nobody else can claim a digital copy from the same physical book, without buying a new copy.

I would also be entirely unsurprised if each ebook was personalised, containing the image of your signature, so that if you gave a copy to someone else they'd know. I also see no mention of DRM (but the FAQ mentions using Calibre to convert ebooks, which suggests they don't use it).

Unix

Terran Computational Calendar Introduces Minimonths, Year Bases, and Datemods 209

First time accepted submitter TC+0 (3672227) writes "Inspired by comments regarding its first incarnation, the Terran Computational Calendar's recent redefinition now includes dynamic support for 'leap duration', 'year bases', and 'datemods'. Here's the new abstract from terrancalendar.com (wikia mirror) captured at 44.5.20,6.26.48 TC+7H:

Synchronized with the northern winter solstice, the terran computational calendar began roughly* 10 days before the UNIX Epoch. Each year is composed of 13 identical 28-day months, followed by a 'minimonth' that houses leap days (one most years and two every 4th but not 128th year) and leap seconds (issued by the IERS during that year). Each date is an unambiguous instant in time that exploits zero-based numbering and a handful of delimiters to represent the number of years and constant length months, days, hours, minutes, and seconds that have elapsed since 0TC (the calendar's starting point). An optional 'year base' may be applied to ignore erratic leap duration. Arithmetic date adjusting 'datemods' can be applied to define things like weeks, quarters, and regional times."
Transportation

The Best Parking Apps You've Never Heard Of and Why You Haven't 163

Bennett Haselton writes "If you read no further, use either the BestParking or ParkMe app to search all nearby parking garages for the cheapest spot, based on the time you're arriving and leaving. I'm interested in the question of why so few people know about these apps, how is it that they've been partially crowded out by other 'parking apps' that are much less useful, and why our marketplace for ideas and intellectual properly is still so inefficient." Read below to see what Bennett has to say.

Comment Not actually sou (Score 5, Interesting) 77

The Videocore IV on the Raspberry Pi (which totally kicks arse, BTW, it's a beautiful, beautiful processor. Did you know it's dual core?) currently doesn't have an open source compiler that's any good[*] which I'm aware of. I have tried porting gcc, and got a reasonable way into it, but ground to a halt because gcc. I know another guy who's similarly about half-way through an LLVM port. And Volker Barthelmann's excellent vbcc compiler has a VC4 prototype which makes superb code, but that's not open source at all.

Without a compiler, obviously the source isn't much good, although the VC4-specific code is really interesting to look through.

In addition, having done a really brief scan of the docs they've released, this isn't what the article's implying: what we've got here looks like the architecture manual for the QPU and the 3D engine. The QPU is the shader engine. Don't get me wrong, this is awesome, and will allow people to do stuff like compile their own shaders and do an OpenCL port, but I haven't seen any documentation relating to the VideoCore IV processor. The binary blob everyone complains about runs on that.

It does looks like the source dump contains a huge pile of stuff for the VC4, so maybe they're going to release more later. But even incomplete, this is a great step forward, and much kudos to Broadcom for doing this.

[*] I have done a really crap port of the Amsterdam Compiler Kit compiler for the VC4. It generates terrible, terrible code, but I have got stuff running on the Raspberry Pi bare metal. It's all rather ground to a halt because there's still a lot of stuff to figure out in the boot process, but interested parties may wish to visit http://cowlark.com/piface.

Rap Genius Returns To Google Search Rankings 115

theodp writes "After being punished by Google for manipulative SEO tactics, a contrite Rap Genius says it's back in Google's good graces. 'It takes a few days for things to return to normal, but we're officially back!' reads a post by the Rap Genius founders. 'First of all, we owe a big thanks to Google for being fair and transparent and allowing us back onto their results pages. We overstepped, and we deserved to get smacked.' Rap Genius credits some clever trackback scraping programming for its quick redemption, but a skeptic might suggest it probably didn't hurt that Rap Genius' biggest investor, Andreessen Horowitz, is tight with Google."

Comment Re:Watch out (Score 1) 99

...actually, I misread the chart. GEO is 3.8km/s from LEO. Lunar orbit is 2.4km/s if you transfer from GEO, giving a total of 6.2km/s. If you go straight from LEO to lunar orbit, it's only 4.1km/s... barely more than GEO. So, yeah, I reckon a technology demonstrator is definitely doable right now.

Comment Re:Watch out (Score 1) 99

Even better --- they've just demonstrated the ability to go to GEO, which is about 14km/s from the Earth's surface. Lunar orbit is only another 2.4km/s, and the moon's surface another 1.6 on top of that!

Chances are that with the technology they have right now, that is, using a modified F9 with the GEO upper stage, they could send a probe on a free-return trajectory to the moon. Or even easier, an impactor. I suspect they won't; Elon Musk appears to have his sights firmly set on the upgraded F9 Heavy and the rocket-landing Dragon, and with that setup you could probably remote land a complete Dragon capsule. I'd be really interested to know what sort of delta vee the Dragon's internal rockets will have...

Comment Re:First (Score 5, Interesting) 250

As an interesting addendum:

Luna-9's pictures were sent back using one of the standard encodings used for wireless newspaper photography transmission. During the transmission, the Jodrell Bank radio telescope in the United Kingdom was listening in (well, wouldn't you?) and the astronomers there recognised the encoding, phoned someone at the Daily Express, and as a result the first pictures from the surface of the moon ever were printed in a British newspaper while the USSR was still wondering what to do with them.

There is some speculation that the encoding scheme was picked deliberately to make sure this happened...

Comment Successfully landed (Score 5, Informative) 90

CCTV's live coverage showed a textbook landing and solar array deployment, including some very shiny live pictures from the descent imager. Next steps are self-testing, instrument deployment and releasing the rover, which they've said will take up to 24 hours. Although I'd imagine that they'll release images from the panoramic mast camera as soon as possible.

Comment Re:Lets try to clear up some missinformation here (Score 4, Informative) 98

The RPi is an ARMv6, while this (along with pretty much every other modern ARM device) is an ARMv7. The ARMv6 has hardfloat but implements a slightly different version of the spec. Most OSes have standardised on the ARMv7 version which means that their code won't run on the ARMv6. So Debian armhf will run on this but will not run on the RPi: you have to use Raspbian instead, which is a version of Debian specifically compiled for the ARMv6. (Of course, Debian armel will run on both, but then you don't get any hardware floating point support.)

The Broadcom GPU is significantly awesome. It is, however, almost totally undocumented. There's a reverse engineering project which has mostly nailed down the instruction set, and there are even some C compilers for it (one of them is mine!) even though there's no gcc or LLVM support for it. You can write programs in C and run them on the bare metal. Unfortunately the GPU doesn't support double-precision float and the MMU is kinda weird, and it's probably going to be slower than the ARM for non-DSP-heavy code anyway, so it's unlikely you'll see Linux for it any time soon. But it's a beautiful, beautiful architecture to write code for. (And it's dual core! Not very many people know that...)

Comment Re:Units! (Score 1) 216

Back in 2009, a UK artist set up an... installation, I suppose you'd call it... which was 1301 flourescent lighting tubes in a field under a 400kV megagrid power line. It's worth checking the pictures out, as they're actually quite striking:

http://io9.com/5204842/a-field-of-light-sabers-powered-by-ambient-electricity

The total amount of power used here would be negligible, of course. But I'm surprised they didn't come down on him for improper disposal of mercury...
Privacy

Seattle PD Mum On Tracking By Its New Wi-Fi Mesh Network 107

An anonymous reader writes "The Stranger reports that Seattle's police department has installed a Wi-Fi mesh network paid for by the Department of Homeland Security. FTA: 'The SPD declined to answer more than a dozen questions from The Stranger, including whether the network is operational, who has access to its data, what it might be used for, and whether the SPD has used it (or intends to use it) to geo-locate people's devices via their MAC addresses or other identifiers.'"
Encryption

NSA-resistant Android App 'Burns' Sensitive Messages 183

angry tapir writes "Phil Zimmermann's Silent Circle, which halted its secure mail service shortly after Lavabit, has released a messaging application for Android devices that encrypts and securely erases messages and files. The application, called Silent Text, lets users specify a time period for which the receiver can view a message before it is erased. It also keeps the keys used to encrypt and decrypt content on the user's device, which protects the company from law enforcement requests for the keys." Seems similar to pieces of the Guardian Project.

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