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Comment Re:Not yet... (Score 3, Informative) 943

Sorry, this is complete crap.

I'm going to compare the USA 1,5,10,25,100 system against the very common 1,2,5,10,20,50,100 system (125 system, for short.)

By my calculation (done by hand, so may be a little out) to make all the quantities of change from 0 to 99, the USA system needs 470 coins, the 125 system needs 340 coins. The only quantities for which the USA system needs fewer coins are 25, 26, 35 and 36, for which it is one coin more efficient in each case.

If you took away the 2c coin to have 1,5,10,20,50 (i.e. a 20 and 50 instead of a 25 compared to the USA system) you'd still need only 420 coins (vs 470) for all change from 0 to 99c.

The 125 system works so well because the denominations are nearly equally spaced logarithmically. Starting with 1, you get the next denominations by multiplying by 2, 2.5, 2, 2, 2.5, 2. In the USA system, the multipliers are 5, 2, 2.5, 4. It is those large multipliers (5 and 4) which make the system so inefficient.

If you wanted to span the 1-100 range with just four coins, I believe 1, 3, 10, 30 would be optimal, as it is closest to logarithmic spacing. (Actually, 1,3,10,32 might be better, but that would be a real pain to make change with.) (Even more efficient would be a true logarithmic system: 1,2,4,8,16... or 1,3,9,27,81,... or 1,4,16,64,256... but none of these mesh well with our decimal system.)

On what evidence do you know "THE AMOUNTS MOST COMMONLY NEEDED"? Even accepting your unsupported claim "the very large majority of "change" needed is less than 50 cents", for each amount of change 0 to 49 cents, USA system needs 185 coins vs 145 for the 125 system, so you fail on this count too. If you remove the 2c from 125 and consider only change less than 50c (effectively removing the 50c from the 125 system as we'll never use it, so denominations are 1,5,10,20) then you *finally* get marginally ahead: 185 vs 190. Against this, the 125 system is about one coin better for every number from 50c to 99c, so your 'very large majority' will have to be greater than 90% to even get marginally ahead. (And remember, this is without the 2c, which the 125 system would normally have.)

Comment Re:It's small (Score 1) 122

Are you conflating RTGs and reactors? I associate thermocouples with RTGs, not reactors, and a cursory wikipedia search didn't find any reactors using thermocouples.

RTGs rely on the natural decay of the radioactive fuel, whereas reactors use a chain reaction to accelerate the decay of the fuel. Voyager etc. use RTGs with thermocouples. The device here is an actual reactor, with a control rod and neutron reflector. I'm aware that the U.S.S.R. built reactors for space. Wikipedia lists a few NASA reactor projects, but I'm not sure any of them actually flew. I'm not aware of a reactor being used in an interplanetary probe.

Comment Re:Doesn't the Tolkien estate... (Score 3, Insightful) 211

None of us know whether WB have the rights to make the slot machines, whether for casinos or Toys-R-Us, as we haven't read the contracts.

We also don't know that money will soothe the estate's hurt feelings. If the parties settle and the slot machines remain, then it was about the money. If they settle and the machines go, or it goes to trial and the estate insists all along that the machines must go, then it isn't (at least entirely) about the money. It is too soon to rush to judgement on this.

Comment Re:Doesn't the Tolkien estate... (Score 3, Informative) 211

Taking a flippant comment seriously:

Ngaruahoe, which played Mt Doom for the distant shots, is not erupting. Ruapehu, an adjacent larger vulcano which played Mt Doom in some of the close ups, has recently had its warning levels upgraded. It also is not erupting, but is considered more likely than normal to erupt in the near future. Nearby Tongariro (opposite side of Ngaruahoe from Ruapehu) had a brief minor eruption in August.

Comment A bunch of random thoughts (Score 2) 141

So each tray gets its time in the sun while going up the tower, and in the shade going down (or vice versa). It seems this would work well only if the plants you are growing are happy getting half the sunlight available at your location. I'm sure you could get a similar effect in horizontal format with little difficulty.

If you can get friction low enough, you might be able to make the whole thing run simply by watering the plants at the top of the down part of the cycle, so the weight differential makes it go.

Scientific American had an article on vertical farms some time back (paywalled here.) As I recall, they had a much more energy intensive design (growing lights etc.) My objection was that for anything like that you could make work in a sky scraper, you could much more cheaply put the same technology out in rural areas.

The Singapore plan only works if there are areas you're happy to cast into shade (and block views from) with these towers. They can't be close together, or they'll be in each other's shade.

Incidentally, Singapore's climate has remarkably little annual variation. The hottest month has average high temperature of 31.7C, the coldest month has average high temperature of 30.0C. Rain is more variable, but still by less than a factor of two through the year. (This is not from personal experience.) If anyone knows of somewhere with less weather variability, I'd be interested to hear of it.

Comment The RNA world (Score 3, Insightful) 658

Dinosaurs? Pah! A mere 65 million years away - practically on our chronological doorstep. I'd send a (very very well sterilized) robot back to bring me samples from the RNA world. Then I'd try to find out what preceded the RNA world, jump forward a bit to try to find the origin of the eukaryotes and maybe then go for filling in the minor details, like observing the Cambrian explosion.

Brief explanations:
The RNA world is a hypothesized (but very plausible) stage in evolution where RNA performs the functional roles currently filled by proteins and the genetic role currently filled by DNA.
Eukaryotes are the complex cells with a nucleus, including all known multi-cellular life plus some single celled life (e.g. amoebae.)
The Cambrian explosion was a period about 530 million years ago when multi-cellular life suddenly appeared in a great profusion of forms.

Comment Re:Nothing like what key says about other Dotcom n (Score 4, Informative) 53

John Banks isn't really necessary for the government. There are 121 seats, National (the main governing party) holds 59, ACT (John Banks) 1. Parties with which National could reasonably do deals to pass legislation (or even negotiate a coalition with) are New Zealand First (8 seats), Maori Party (3 seats), United Future (1 seat.) So they could distance themselves from John Banks and still continue to govern as an effective minority government. The opposition Labour Party effectively lead a minority coalition government in this way for years.

Comment Re:Prior Art? (Score 5, Informative) 98

No, the GPL doesn't work like this. Having violated the GPL on this code, Twin Peaks are no longer licensed. They cannot reacquire a license simply by coming back into compliance. They need to explicitly be relicensed by the copyright holder (Red Hat), who are not likely to do so in this case.

It has been the norm for the resolution of GPL violations that the violator comes back into compliance and then is relicensed, because Free Software organizations are generally more interested in cooperation than conflict, but there is no legal requirement for Red Hat to follow this norm.

You can read the GPL here:
http://www.gnu.org/licenses/gpl-2.0.html
http://www.gnu.org/licenses/gpl-3.0.html

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