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Comment Re:Aren't HPS lights more efficient than LED? (Score 1) 372

High Pressure Sodium street lights are around 100 lumens per watt. HPS can be as low as 50 or as high as 150 depending various factors.
LED street lights are also around 100 lumens per watt, but they vary even more widely.
A theoretically perfect light source with a wavelength of 555 nm would emit 683 lumens per watt, so both LED and HPS are about 15% efficient.

Even the best HPS is less than 25% efficient, and the best LED isn't much better at just over 35%.
At 14.5 lumens per watt, an A19 incandescent 60 Watt bulb (i.e. a "normal" bulb) comes the closest to 97%, but it's 97% inefficient.

Comment LED street lights are over 100 lumens / watt. (Score 1) 372

Yes, it's you - you are so last year.

We aren't talking about those cheap $10 bulbs from Home Depot that get a measly 84 lumens/watt.

Commercially available LED street lights like Cree's LEDway have been over 100 lumens / watt since 2013-03, making them more efficient than high pressure sodium even without considering their arguably superior focusing and CRI.

Comment Re:Hooray for fusion! (Score 5, Informative) 140

If I'm crunching the numbers correctly, 1 gram of Boron produces 25,000 kWh of electricity - assuming perfect capture, 100% boron-11 and no other loses. (Granted, all unrealistic assumptions, but it's a starting point.)

If we replaced all electric generation on the planet (about 20 trillion kWh / year) it would take 800 tonnes of boron per year.

Turkey has the largest known Boron deposits at over a million tonnes or 1,200 years worth. And there are several other countries with large (thousands of tonnes) deposits as well, and that's just the Boron we know about.

All really rough estimates, but I don't think will run out of Boron fuel any time soon.

Comment Re:Authors can use these tools too. (Score 1) 184

What would be the point of mutating the way you write so that you can no longer be identified ...

If you are writing characters for a story, you might want them all to have unique, easily identifiable speech patterns.

Also the traits that stand out and identify you most are probably really annoying.
You might want want to reduce them.
For example, you might want to not use the phrase "might want" nearly so much if it was brought to your attention.

Comment How can you "violate" the GPL? (Score 1) 394

If you don't comply with the GPL, than at most, you are violating copyright law.
Following the GPL is optional. It grants you certain rights if you follow it.
You might have those rights anyway, or you might decide it's better to pay the fines for copyright violation, but I don't see how you can be forced to follow the GPL.

Comment Re:Stealing subtitles? (Score 1) 284

That's what I was thinking. Technically, the copyright owner owns the rights to derivative works.

In the sense that you need their permission, yes.
But the original creator does not own all the rights - you will also need the permission of those that created the derivative.
You have to satisfy both of them to publish legally.

Comment Uh ... No. (Score 5, Informative) 152

First, regarding the so-called sugar battery;
It's really a sodium-ion battery.
They claim a 20% increase in power storage over a lithium-ion, which probably means a 20% decrease in cost, best case.
Sodium-ion batteries have cycle problems - after about 50 charge/discharges, they typically have 50% of their original capacity. They don't even talk about this, so I'm betting they haven't solved the problem.

Second, about lithium-ion batteries;
Lithium isn't rare - you could extract it from sea water for about 3 times what it costs now. Even at that price it wouldn't mean much to lithium-ion batteries, because despite the name, lithium isn't the primary ingredient, nor is it the most costly.

Envia's breakthrough battery is a lot better at 3 times the energy density and half the cost, and it's a lot closer to market.

Comment Re:Where is the line? (Score 1) 246

Anyone can sit down and write down liscense plate numbers.

And in theory you could hire an army of people to stand on every corner and record every license plate they see - and that would be an invasion of privacy.

The problem isn't the scanners. That's how they keep tabs on everybody's movements. The problem is that they think it's OK to keep tabs on everybody's movement.

Comment Re:Nitrogen... (Score 1) 63

as far as I understand it, there really isn't a good source of nitrogen on mars (atmosphere 95% CO2, 3% N2 on mars, vs 78% N2 and 20% O2 on earth).

The atmosphere of Mars may only be 3% nitrogen, and only .6% the density of Earth, but it's still a lot in absolute terms.
Easy to get, and unlikely to run out.

With a reactors worth of energy and maybe a tonne of compressor, it's reasonable to liquify and separate it into CO2, Nitrogen, Argon, and water.
My very rough estimates are about 10kWh to produce one kg of liquid nitrogen (about 1m^3 worth of 100kPa air).
A decent sized habitat has maybe 200m^3 of air.
A megawatt power plant, and you could fill that in less than a day.

Comment Re:DIscussed the business case with media partners (Score 1) 189

The first moon landing was watched by an estimated 600 million people.
The Olympic games are watched by an estimated 3.2 billion.
Sure, a lot of people would watch the first manned Mars mission, but the case for "more people watching than watch the Olympics" is still weak.

Think how many SciFi shows have been canceled because they cost too much to produce. Now consider that "too much" is still less than 100 million a year, or about 1.6% of six billion.

Comment How about an affirmative defense instead? (Score 2) 93

IMO the problem with software patents is that there is no way to know if your software infringes one.
Only #4 "Infringers should avoid liability if they independently arrive at the patented invention." even comes close to addressing the problem.

My suggestion is this;
    Any computer built more than 1 year prior to the filing date of a patent, does not infringe that patent, regardless of how it is programmed.
    Likewise any software that runs on a computer built more than 1 year prior to the filing date of a patent, does not infringe that patent.

Note that a strong argument can be made this is already true. I think we should lobby for a law that spells it out explicitly.

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