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Comment: Later in life (Score 1) 541

by SimonInOz (#47526821) Attached to: Laser Eye Surgery, Revisited 10 Years Later

Laser surgery gives, in general, very good fixed correction. It is excellent for people under 45 with vision that needs correction. There are occasional failures, yes, but they are quite rare.

But what about later in life (hello, 50) when your lens hardens and you can't focus it any more? Laser surgery will achieve nothing. You are still stuck with reading glasses.

Well, I had -7 vision and was mightily sick of being blind without glasses, found contacts a drag, and it's all damned expensive. My vision with my (very expensive) glasses was excellent, with contacts acceptable, but it was all annoying.

So I got lens replacement surgery. It's the same operation as for cataracts, but voluntary. And expensive (AUD 10,000). The replacement lenses are not focusable, so I got lenses with three focus points - close (reading), medium (screen, and distance. A Zeiss trifocal implantable lens.
The operation was quick, but unpleasant (you are almost, but not quite unconscious - not nice). Recovery involved many, many drops for a few weeks gradually diminishing to none.

Result - daytime vision is excellent, both near and far. I can read, compute, play sports.
Night-time vision is not so good, you get some haloing and other artefacts. I can drive ok, but stargazing is not so great.

These lenses will not harden further so my vision should stay the same for the rest of my life, which is nice.

On the whole I am pleased. It's certainly a joy to go swimming without concern, see in the rain, and even water ski. Amazing after a life of really, really poor vision.

I researched the surgeons, checked the research, and balanced the results against the side effects and risks. In fact, the risk of actual permanent damage - ie blindness - are very low indeed. After all, they do these operations by the thousand in Africa (look up Fred Hollows) in what must be poorer conditions.

Laser surgery was not for me - that would indeed have corrected my main vision problem, shortsightedness, but I would have been unable to read or compute without reading glasses - and where's the fun in that?

It's amazing to wake up in the morning ... and be able to see.

Comment: Rotation (Score 4, Interesting) 79

by SimonInOz (#47420877) Attached to: Study: Why the Moon's Far Side Looks So Different

The moon became tidally locked within a few million years after its formation (around 4.5 billion years ago), so it's been tidally locked for over 4 billion years.

But really, did the earth stay hot enough for "a few million years" - hot enough to affect the locked side of the moon more than the other?

The moon would have cooled somewhat faster, being smaller, but this theory requires the earth to stay hot enough to affect the "earth side" of the for a very long time after the moon has cooled enough to solidify.

Comment: Re:Now I'm confused ... (Score 2) 380

by SimonInOz (#47329141) Attached to: New Chemical Process Could Make Ammonia a Practical Car Fuel

Two reasons:
* storage - ammonia is a liquid at fairly low pressure (150psi/1000kPa). [Unlike hydrogen, which requires very high pressure (10,000psi/70,000kPa), and generally cooling. And the damned stuff seeps though anything (dem H2 molecules are kinda small)]
* energy density - as a liquid, ammonia has about half the energy of petrol (gasoline). Not bad - certainly better than the average battery. Vastly better (7x) better than hydrogen

It's not delightful stuff to handle, but beats the heck out of a highly flammable liquid .. like petrol (gasoline)! It's not very flammable at all, actually, though you can burn it in combination with other things.

Also, if it escapes, it turns into gas - which is easier to get rid of than a liquid.

Comment: Sensors - for quakes? (Score 1) 90

by SimonInOz (#47258839) Attached to: Privacy Worries For 'Smart' Smoke Alarms

There are quite a lot of sensors, and processing power in a Nest gadget. It includes a motion sensor, and that data could be extracted to a database, giving us an absolute plethora of sensors spread across homes (ok, mainly rich homes, and certainly a lot in California).
Such a wealth of data would surely be brilliant for earthquake monitoring.

Comment: Re:Caravan (Score 1) 310

Pah. It was my boat all right, but it was relatively cheap - and I did get paid pretty well. Or at least it felt that way - no family, no mortgage ... those were the days.

The card readers were pretty expensive, and I did not think they'd survive the salt. I stored programs on little plug in memory modules which worked well. Great little gadget.

Comment: Re:Submarine (Score 1) 310

Hah. Nuclear sub. Nice and stable, well lit - easy.
And you even had power!
My little boat rocked about a lot, all power came from a small solar panel, it was rather damp.

Mind you, I didn't have to salute anyone or wear a uniform (or wear anything, come to that). And the view was pretty extensive.

Comment: Re:Caravan (Score 4, Interesting) 310

The inside of a small yacht, crossing the Atlantic.
I was sailing (an Iroquois 30' cat, in case anyone's interested), and found sight reduction (yes, a sextant was involved) rather tedious. So I wrote a program for my HP calculator to do the calculations.

Those HP41C calculators were really neat.

Comment: eight hours isn't very long (Score 3, Interesting) 187

by SimonInOz (#46744819) Attached to: First Glow-In-the-Dark Road Debuts In Netherlands

I used to live in the Netherlands, and I can confirm winters are cold and dark. Days are not very bright either. So an eight hour life (yes, I RTFA) for these very cool glowing roads is not going to cut it - nights comprise 16 hours of darkness in midwinter.
It should work well in the summer, when days are brighter and nights shorter.

But I think a backup is required, destroying the whole point.

But it does look very cool, doesn't it?

Comment: Re:risk aversion (Score 1) 112

by SimonInOz (#46559615) Attached to: Electric 'Thinking Cap' Controls Learning Speed

>> refactor the law, its bloated, confusing and unmaintainable ... what? ...

Or did you mean

refactor the law, it's bloated, confusing and unmaintainable.

Or possible

Refactor the law, it's bloated, confusing and unmaintainable.

Dammit, you're supposed to be a geek. Learn the grammar.

And you are right, I haven't had my coffee yet.

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