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Comment Re:Data transfers (Score 5, Interesting) 245

From here,

The total cost of the Voyager mission from May 1972 through the Neptune encounter (including launch vehicles, radioactive power source (RTGs), and DSN tracking support) is 865 million dollars.

and

A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter.

That's $0.001384 per bit. There are 1120 bits in an SMS message. That's about $1.55 per SMS. Not exactly cheap, but then Vodafone don't have coverage beyond Pluto.

Comment Re:Nice headline (Score 1) 178

I mean, a chess computer has no concept of a plan,

That really depends on the program, now doesn't it? I'd be very surprised if the programs didn't cache some of their computations to immediately generate the countermove if the opponent moves as expected, and use the reminder of their turn to further simulate future moves. After all, it's an obvious optimization, and that's what plans are - now I do this, then he does that, then I respond with this move, and so on.

That's not what I'm talking about. I am a club player of moderate ability - I would have no hope against a modern chess programme like Fritz on a basic PC (even on that hardware, it's at least comparable to a top-50 player). However, I can look at a position and decide that to win, I need to, say, get my knight to a particular outpost, and drive home a passed pawn and promote it. A computer doesn't think like this.

and even Kasparov or Topalov or whoever can only calculate a handful of positions a second.

I wouldn't be too sure of that. A brain is basically a massively parallel computer, simulating the likely events in your immediate vicinity all the time - and in the case of humans, using abstract thought to simulate far away places as well. It's likely that there are hundreds, if not thousands, of plans that are considered subconsciously but rejected because of some obvious flaw, freeing the conscious mind to only examine the most promising ones in detail.

I was talking about brute force computation, which has been measured. I forget the precise result, but I think you're talking something like 3 or 5 positions a second. Those players, and even I derive most of our ability from pattern recognition, while the computer is powerful because it performs an (optimised) search on a tree of possible continuations. There's a fundamental difference in how humans and computers play chess.

Comment Re:Nice headline (Score 1) 178

Draughts has only been solved on the 8x8 board, and the best programmes for the 10x10 version caught up with the top humans a few years back.

It's interesting to speculate about how the advancement of playing software might hint at how tactics and strategy are balanced for the various board games. I mean, a chess computer has no concept of a plan, and even Kasparov or Topalov or whoever can only calculate a handful of positions a second. Of course, the most interesting part of that problem is how to pose the question.

Comment Re:Sounds like beamforming (Score 1) 221

To be honest, I'm not clear on how it scales. I've only seen presentations on this sort of thing for, say, two mikes and maybe five speakers. The thing about background noise is that it has to be filtered out somehow, or what you get is essentially white noise. Maybe localizing the sound helps in that regard. I don't really know.
Science

Submission + - Irish Min. for Science to Launch Creationist Book (politics.ie) 1

__aamkky7574 writes: Conor Lenihan, the Irish Minister of State for Science, Technology, Innovation and Natural Resources, is scheduled on Wednesday 15 September to launch an anti-evolution book entitled The Origin of Specious Nonsense". The author, John J May, is a public relations person, marriage counsellor, poet, actor and ex-religious leader, but doesn't claim to have any science background in his biography.

In his book's synopsis on his website, he claims he will "unceremoniously unashamedly and unmistakably going to expose the fiction of evolution". In his quotes, he claims that "It is sacrificing reason on the alter (sic) of treason to accept that the greatest construction of all time.. a human being with a brain is the result of chance, randomness and destructive mutations. It is the irrational three legged chair of hopeless speculation that bears no resemblance whatsoever to reality and observable functioning perfect order." When contacted, Lenihan's office confirmed that he was indeed due to launch the book.

Previously, another minister in the same government, the Tanaiste (deputy Prime Minister) Mary Coughlan, hit the headlines when she claimed that Albert Einstein formulated the theory of evolution (http://www.independent.ie/national-news/coughlans-no-einstein-after-gaffe-at-smart-economy-launch-1890227.html).

Comment Re:Don't sit down = Immortality (Score 1) 341

the researchers found that women who sit more than 6 hours a day were 37 percent more likely to die than those who sit less than 3 hours; for men, long-sitters were 17 percent more likely to die

You know... I'm pretty sure everyone is 100% likely to die...

It's probably a quote or a rephrasing from the paper. In that case "during the period of the study" is implied.

Comment Re:Noise/Light Sensitivity/Optics (Score 1) 289

It's an interesting question. Pixels return an intensity value proportional to the mean intensity over their surface, so I'd imagine you could average groups of 2x2 or 3x3 (etc.) pixels to trade resolution for sensitivity. Alternatively, you could up the gain on each pixel, which as Greymist points out would reduce your signal to noise ratio.

Comment Re:Depth of Field (Score 1) 255

That's refocussing by post-processing, not infinite depth of field. In each of their processed photos, there are objects in and out of focus.

As an aside, I've not read their paper, but that device has to have a large number of pixels per microlens, meaning it's significantly lower resolution than an equivalent camera without microlens, something they've ignored in their comparison photos.

Comment Re:What is up with this site lately? (Score 1) 161

I'm a much more recent arrival at slashdot than that. An engineering PhD, I also come here for the technical focus and for the commentary. The community really shows its knowledge base in topics in computer science, astronomy and maybe particle physics, and its passions in copyright and other areas of IP, privacy and human rights. When the stories drift away from those areas, the comments can be fairly inane.

Comment Re:Depth of Field (Score 1) 255

Call me back when they fix the depth of field issue. The whole scene needs to be in focus so that when my eyes aren't looking at precisely what the director wants, my eyes don't try to focus on something that can't be focused on.

I'm unclear: is this a problem you have specifically with 3D, or with cinema in general? Every imaging system has limited depth of field. What you're asking for is technically impossible except in animated films.

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