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Comment Very Impressive (Score 1) 52

The image posted in the article seems to be the output of some kind of scanning microscope (note the vertical scan lines). Perhaps a 3-channel confocal "optical" microscope, which scans the image separately with red, green and blue laser beams, then combines them into a final image (like a "color" TV image). So it's really a false-color rendering of 3 mono-chrome images (but "true" color in the sense that each beam captures the actual color response of the inks in the printed image (like a TV etc).

The article doesn't mention the resolution of the actual image but, eyeball counting the scanlines, it looks like somewhere around 160x80 or maybe 200x100. With 25,000 dots per inch, that's about 984 nanometers per dot, slightly larger than the wavelengths of visible light (380-870 nm).

The limit of optical resolution is about a half-wavelength, so there seems to be enough headroom left for improving this result.

Comment Sea-level threat? (Score 5, Interesting) 289

Sure, when you live on an island barely six feet above sea level, passing hurricanes have threatened (and have succeeded in the past) to wipe these islands clean. But the threat of sea level changes, which have been slowly rising since the last Ice Age, is moot because, in recent times, most of these Pacific atolls have grown in size, due to increasing biomass of growing coral.

Cutting emissions, IMHO, will have no observable effect on these islands. But I can't blame the natives, though, for trying to get the rich nations of the world to give them free transport to higher and safer havens.

Comment Re:Spaghetti sort (Score 1) 82

No. It is a _total_ ordering over the relation "=" in the sense that all pair of elements in the linear are comparable, i.e. elements a and b must satisfy "a=b" or "b=a", which is the requirement for "totality".

In a _partial_ ordering (such as a collection of tree-structured elements) not all elements are necessarily comparable using "=", e.g. elements in different paths.

In plainer English: the strands of a spaghetti-sorted collection are totally ordered by length when traversing along the strand axis towards the table. I.e. each element traversed is greater or equal in length to _all_ ('totality') of the remaining elements yet to be visited.

Comment Re:Spaghetti sort (Score 1) 82

> It aligns their ends against the same reference ( the table top ),
> which has nothing to do with sorting.

But in the process of alignment, a linear ordering is imposed in one dimension, along the axis of the spaghetti rods, such that if you traverse this axis towards the table top, you are guaranteed access to the members of an ordered collection, tallest member first. Quite often that is an acceptable solution, especially if you are only interested in the tallest strands. Perhaps not a general solution to the sorting problem.

Mathematicians insist on perfect, general solutions. Scientists and engineers are often quite satisfied with "trade-off" solutions that work for the problem at hand.

Comment Re:Spaghetti sort (Score 1) 82

> While those methods can no doubt solve certain problems much more quickly than
> conventional serial or even conventional parallel computers, there are certain problems that
> they simply can't help with.

The price paid for surpassing "optimal" general solutions of a problem is that they won't work on all instances of the problem. Quite often that is an acceptable price. It's a trade-off.

Comment Spaghetti sort (Score 1) 82

Perhaps the only way to avoid the mathematically imposed restrictions on conventional computing machinery would be to (literally) use a different mechanism. One that is inspired by the nature of the problem.

For example, consider the problem of ordering a collection of random-length pieces of uncooked spaghetti. They can be ordered in O(1) time by merely grasping them in your hand and striking them against a table top. Ordering 500 strands takes no more time than 50 (ignoring preparation time). Scaling up is merely a matter of finding a bigger hand or table top.

For comparing strands of DNA consider using a 'chemical computer' based on the transcription of DNA in to messenger RNA, which is the 'algorithm' employed by Nature to encode the DNA sequences. Such a machine, in solution, equipped with customized sequences of interest, could theoretically recognize any desired DNA sequence in O(1) time (up to chemical reaction times).

So a simple solution to a complex problem. I'll leave it to you students to work out the details. ;-)

Comment TFA: "For the first time in recorded history..." (Score 1) 292

History has been recorded now for thousands of years, but it is only thanks to satellite technology, starting in the 70's, that we were able to observe and detect hurricanes over the vast Pacific region. So the use of the phrase "first time in recorded history" is a bit presumptuous, IMHO.

My guess is that this has certainly happened before but nobody able to observe and report it. Except ships at sea. And the Cat 4 storms probably sank them before they could get the word out.

Comment Re:If Only (Score 2, Informative) 118

> ...prove that such rigor isn't required of climate science...
One way to evaluate scientific hypotheses is to look at what the events they predict, then observe nature to see if the predicted events correspond to reality. In that sense, modern climate science is an epic fail because the "global warming" predicted by their models failed to happen. (Prompting the climate-alarmist "true believers" to switch to 'climate change' (so, up or down, can't lose))

> ...most climate scientists have done a good job of keeping corporate interests away from their research...
BS. 'Big Oil' is a red-herring to divert attention away from 'Big Government', whose grants and funding tend to force researchers to become, in effect, lobbyists for political activism in order to 'pay the rent'.

Comment Re:black balls (Score 2) 234

'High albedo' works two ways. Yes, during the day, it would reflect sunshine and reduce heat absorption. But at night it would tend to prevent heat already absorbed from escaping (reflects it back into the water). So at night black would be best, allowing more heat to escape. Google 'black body radiation'.

Water is already, in effect, a black body radiator, so IMHO the black-ball radiators would not be a bad solution because it radiates internal heat maximally and also is supposed to inhibit algae growth (assuming it provides 100% cover).

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