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Comment Why were those cold fusion experiments done?. (Score 1) 344

Here's something that the original article did not really discuss...

Most of science proceeds by small steps. Someone notices an anomaly. Someone manages to repeat it. Someone manages to extend the current theory to fit it. Someone may come up with a radical theory that also fits. Someone finds another prediction from the radical theory, and looks for verification of that. And so it goes on.

We know that there is a large potential barrier to getting light nucleii close enough to fuse. We can whack a few particles into each other in colliders and explore quite how hard they are. This tells us about the particles and forces involved, but colliders use a lot of energy, and we get almost none back from any fusion. We can try things like stellerators or tokomaks, which are designed to provide lots more collisions of one particular type much more efficiently, and work towards break even. The two positive nucleii will repel each other, but we can replace the electrons with mesons, which are more massive and sit a lot closer to the nucleus, so that gets around some of the electrostatic repulsion; but mesions have a short half-life so we have to keep making the things. All this is not very successful, but it is logical.

The bit that is never explained is why Fleichmann & Pons expected to produce fusion using electrolysis. Or why Rossi expects whatever he does to produce fusion. What was the anticipated process that provides the squish that gets the nucleii together close enough to cause fusion in their experiment? We know a lot about how much energy or force this takes. We also know a lot about the decay particles that we would expect from fusing particular atoms. It could be that there is some entirely novel means of doing this, and some entirely novel decay modes. As scientists, we are required to hold this as possible in principle, but we do not generally do experiments without a credible positive outcome. If you are investigating a small anomaly, such as the 'extra' energy in the F&P experiment, you investigate an unknown: you do not attribute any energy difference in advance to fusion by an unknown process. William of Ockham had a thing or two to say about this sort of reasoning.

Compare and contrast this with the supraluminal neutrinos investigation. An experiment seemed to say that some particles were travelling faster than light. The likely explanation was that there was an experimental error. The error corresponded to several meters in length at the speed of light (a surprising error, but possible) or a timing error (a few nanoseconds, much more plausible), or something else (including the stated remote possibility of a faster that light particle, which would upset a helluva lot of physics, and no-one really believed). They performed tests to verify their surveying and timing assumptions, and found a timing error in their electronics. A lot of science is dull like that.

Comment Re:Improvements to OCR? (Score 3, Interesting) 66

Suppose you had a bit of your handwriting that you could not read. How do you figure out what you wrote. One thing that I do, and you may do too, is to try and imagine writing the thing, and work out the rhythm of what you are writing. If you can get some sense of how your hand is writing, you may see that what was a 'u', or maybe an 'n' or half of am 'm' makes sense because of the way it joins up to other stuff. We seem to have some sort of kinematic two-and-a-half axis model for writing. We use different muscles if we are writing with a pen (fingers and wrist), a blackboard (wrist and upper arm), a spray-can (upper and lower arm), or a tiny engraving tool (just fingers) and yet our handwriting remains much the same. So some computer that can try and fit the same kinematic model should make better guesses for a word it has not met before than anything that just trained on the shape.

This does not directly transfer to OCR. If you have a page of fixed-width text, then every letter has its own little rectangle, and you can either recognize that using the traditional OCR model, or you can't. However, there is something we can do along the same lines. Suppose you have a document that you guess was rendered from PostScript. If you have a guess for a particular word, and the font it was rendered in; you could render that part of text. You can then degrade that rendered image to mimic the properties of the printing and scanning, and check the fit. The best solution will probably be the one that achieves the best fit with the shortest, and hence most probable bit of PostScript. When you have more text, you can pick up hints from the spacing, the justification, and other larger page layout structures.

I actually worked on OCR, and tried both of these once. It might have worked with a large software team, but I hadn't got one.

Comment Re:Where did it all go right? (Score 2) 290

You are talking about the first French attempt, where they shipped in people as they died from malaria. I was talking about the US one, where they cleared the banks of the canal and build mosquito-proof quarters and fever hospitals whoever they went. That one worked. At the time, there was enough forest to retain enough water. Now, the surrounding forests have been felled, and there is a lot more shipping, but that isn't the original designers' fault.

Comment Where did it all go right? (Score 5, Interesting) 290

There are a few examples of engineering projects where everything went right, or at least better than expected. The UK equivalent plane was the Vulcan bomber, which would have been a stealth bomber by accident: only the upright tail gives it away on radar. The AK-47 has it. The London Routemaster bus had it. The Soyuz lifter has it. The Panama canal has it too. Can you think of any others?

More importantly, can we make everything work like that?

Comment A vote for symbols... (Score 1) 304

I started off programming in Algol in the sixties. I have used symbols and abbreviations.

Abbreviations can give you clashes with variable names. You normally learn what to avoid, but it is easy to have integers i, j, k, and floats if, jf, and kf, and not notice what you have.

That being said, it is a shame we don't have the right symbols on your keyboards. I would like... - Separate single symbols for assignment (:=) equality (==) and perhaps identity, or deep equality - The set cup and cap symbols for logical operations and tests (how many people evaluate CATS and DOGS as CATS and/or DOGS when they write. - A separate decimal and period.

Instead we have all sorts of weird junk, such as the '' symbol on the top right, which only appears in the correct spelling of Lord Xenu's full name. Or something.

Heigh-ho, ain't gonna happen. But we can dream.

Comment Re:I saw a TEDTalk about this . . . (Score 5, Insightful) 142


Google and Tesla are doing different things for good reasons. Tesla makes electric cars, and it needs to go carefully or it will lose its core business and customers. So they start from an electric performance car and gradually work up to an autonomous performance car. Google doesn't make cars, so it is not risking a core business; and their potential customers are mostly people who can't drive or don't trust their eyesight any longer, so anything that lets them potter to the shops is better than nothing. So they start from a new antonomous car, and work up to an autonomous performance car that can play chicken with the Audis on the autobahn.

Two different approaches. One of them is not necessarily wrong.

Comment Re:Unmanned? (Score 1) 196

I was wondering about this. If it was a drifting, unmanned ship at sea it would become the property of anyone boarding it. I would imagine a drifting, unmanned ship above the sea would be subject to the same laws. So, we need another airship to chase it, and board it.

This could all turn delightfully Girl Genius...

Comment Yet another Mac user... (Score 1) 193

Mine is the same story as the others, but a bit further down the line...

When my parents were in their seventies, I had bodged together various Windows PCs for them, but they never were stable. My Mum wanted a new computer, so I suggested they got a Mac, and that is the one she learned to use. This was good for me because I also worked on a Mac, so I could replicate what they were doing. It has had a repair - the modem blew when the house was struck by lightning - and I probably will not be able to update the operating system much longer, but is still going after more than 15 years.

My mum is now 95. She uses the computer for e-mail. I doubt if she would adapt to a new computer now, but her fingers remember how to use the important bits. She also wanted some button that she could poke once a day to let people know she was OK as she lives alone. She does not want a camera looking at her, though. I found an old PowerPC laptop at work without a power supply, and with no camera, and they let me take home. I got a replacement power supply on Ebay, and wrote an AppleScript. When she presses the start button, it powers up, checks the network is up, sends me an e-mail, and then turns itself off. Because it looks like the other computer, she can also use it for her other stuff (she doesn't, but she could).

Once a day, I get this automatic e-mail. If it hasn't arrived by noon, I ring up. Once or twice we have had problems with the network. One problem was the cleaner unplugging the server to plug in the hoover (cured by using a less convenient socket), and once because the server was acting strange (flashing newer firmware cured that). I would do more if she wanted it, but she does not want the fuss.

Comment They ought to teach this in schools... (Score 1) 450

The Ashley Madison scam is not really that different from selling bogus cures to baldness, snoring, erectile disfunction, or cancer, or promising Russian brides, or bogus kickstarter projects (you can usually sport these, but someone must think they are worth doing). The internet can reach people in such numbers that it is even worth posting 'you won't believe..' set of pictures (usually photoshopped) for the tiny advertising rewards. We can either say that this is natural way of things: that the cunning should rip off the dumb, or we can do something about it.

In this particular case, Ashley Madison claimed to have a sex ratio of about 1:6, which might make it compatible with reputable dating agencies. However, it is not likely that there are millions of Smoking Hot Babes Just Waiting For You out there. If Ashley Madison once had one good-looking lady on the books, the AM sysadmin would have got her first. It is not only likely that the Ashley Madison scheme is just as reported, it is almost impossible that it could have been anything else. There might be a real site somewhere, but it is so much more efficient to be a scam.

Ashley Madison is perhaps not a proper subject for schools. However, schools do try to encourage smaller children to be nice to each other, and cautious of strangers. It might be sensible to introduce them to the net alongside instructive examples of pictures that aren't real (Snopes tear-down of the sharks in the flooded mall picture), offers that are too good to be true (pyramid schemes), how to know the person you e-mail is a real person (meet Eliza), and so on. I think this would make most children more aware of what might be happening on the other side of the screen; and it might even discourage the few who might be tempted to run scams when they see how little the returns must be.

Comment Parasites of the internet (Score 1) 519

I have seen this argument and always found it incredible. These people who wish to place pop-up ads have neither invented the internet, nor enabled its growth, nor provided useful or beneficial content; and yet they argue that they are the true owners of the Internet who should be able to tax us for its survival, and that to install ad-blocking filters is somehow 'piracy'. There are other, nobler organisations that use advertising in moderation (Google), and others that try to do without (Wikipedia) - I would not argue that one is right and the other wholly wrong. Both of them manage to live well within the bounds of what I feel is to the general good. But the click bait links, the promises that this 'weird trick' discovered by a mum discovered will free you from ageing or snoring or male pattern baldness, the stupid, stupid stuff that I wish would burn and die, all you are a cancer on the Internet, the beautiful child of all nerds of the world, and I hope the chemotherapy of filtering may earn us a remission, if not a cure. I have not heard from Nigerian princes in a while. No-one has tried to sell me Viagra in weeks. We may win this one too, if we stay firm.

Whew. Sorry about that. But it came from the heart...

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