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Comment Precarious business model (Score 1) 194

It sounds like a precarious business model. Everyone prefers lithium batteries. So long as lithium prices are high enough, you can find a market for cheaper inferior batteries. But high lithium prices will lead to higher lithium production and prices likely coming back down. In building a sodium battery plant, you're gambling on lithium price being sufficiently high most of the time for several decades into the future.

The picture changes if you can make the sodium batteries as good as lithium for at least some market niche, or if your battery plant can easily switch between lithium and sodium (which seems fairly likely.)

Comment Re: Micropayments? (Score 2) 222

Well, part of it is that even a small payment can still incur a psychologically large cost. If each user post here on /. cost one cent to read, would you want to have them load automatically? Probably not, many of them are not worth that much, and you could quickly run up a bill of a few hundred dollars a year on that sort of thing from this site alone. So instead you'd have to take more time to think about what was worth spending even a little on, because it adds up and the price doesn't really match the value to you of the thing you'd be paying for.

Something similar happens when people have metered or capped Internet usage compared to at least nominally unlimited usage.

You really can't avoid this problem unless the micropayment is so small that it is likely not worth the cost to implement. I suppose if I knew that a year's worth of micro payments for me, for everything I use, was no more than about a dollar a year in total, it wouldn't be so much that it would feel like I was wasting money on the Internet. But because the average user doesn't want to spend a noticeable amount ever, and there really aren't that many users in comparison to sites, the resulting pie of money wouldn't be much to split up. (Especially once you reduce the amount to account for lower average incomes elsewhere in the world)

Comment Re:How could the Earth heat it? (Score 1) 96

I've shown the claim is implausible, not impossible. I'd be interested to see what evidence there is to support it.

I don't see the need for the claim from an evolutionary point of view: there is no reason I am aware of to suppose that current tides are insufficient to drive organisms to evolve into terrestrial niches.

Comment Re:How could the Earth heat it? (Score 1) 96

What happened 4 billion years ago is not the point - the claim was made in the context of the 'conquest' of the land by multicellular life, which was only about 0.5 billion years ago (not 1 billion, as I used in my analysis, and so tides were likely only about 15% higher then.) I agree that tidal conditions were very different four billion years ago, and that my linear extrapolation would not apply so far back.

10% (for a billion years, or 5% for 500 million) is a small enough change in distance that we wouldn't expect the recession rate to have changed a lot over that time. This is a somewhat weak point in my argument - the recession rate of the moon is largely dependent on how many Bay of Fundys there are in the world, so the current rate may not be typical. However the argument is strong enough to place the burden of proof on those making the claim: you claim an effect an order of magnitude greater than simple analysis allows for. Show evidence for these tides, or a well founded model which predicts these tides (at the required time.)

Comment Re:How could the Earth heat it? (Score 5, Interesting) 96

1 billion years ago the Earth had 100 to 1,000 foot tides as the Moon and the Earth were much closer

My initial response is "I don't think so." My second response is to calculate, so here goes:
Current distance to moon = 384,400 km = 4 x 10^8m
Current rate of increase in distance to moon = 3.8 cm/year = 4 x 10^-2 m/year.
If this rate were constant over a billion (10^9) years, then a billion years ago the distance to the moon was 4 x 10^-2m/year*10^9year = 4 x 10^7 m closer, or 10% closer. Tidal effect strengths are inverse-cube in distance, so a billion years ago, lunar tides would have been about 30% larger than now.

This doesn't come close to "100 to 1000 foot tides."

Comment Re:I could be missing something (Score 3, Informative) 96

As seen from the moon, the Earth is only about two degrees across, so the proportion of projectiles blocked by it would be miniscule. Even that small effect is reduced (possibly beyond zero) by 'gravitational focusing': projectiles which come towards the moon from the direction of the Earth which would otherwise have missed can be deflected by Earth's gravity such that they hit. (And this happens more often than projectiles that would have hit being deflected so they miss.)

Here is a paper I found on gravitational focusing.

Comment Re:On this I side with facebook (Score 2) 147

Option 2: Active editors. These forums are cultivated, maintained, and very ban-heavy. As a side-effect, the forum can be held responsible for third-party content.

Not true in the US (other than, potentially, with copyright issues and the like).

Remember, the CDA was intended to encourage providers to engage in censorship. Since the previous state of affairs was as you suggest, the way that they were encouraged to censor was to remove liability for material posted by third parties. But since many sites don't care, and the CDA protects them fully no matter what they do or don't do, it didn't really work out. Also other parts of the CDA turned out to be unconstitutional.

Comment Doppler Velocity and Uncorrelated Position Errors (Score 1) 131

The authors suggest that doppler velocity calculations should be immune to the kind of overestimation they claim sampling position measurements suffers from. I don't think this can be the case.

Let's first focus on what is wikipedia claims is the largest source of error: signal delay from the ionosphere. It seems reasonable to assume that this delay changes in a continuous manner with time. However, that means that the (non-shared) error introduced into position measurements as a result also shows up in the Doppler velocity estimations.

Indeed, one can think of Doppler velocity measurements as, at the theoretical limit of accuracy, being just another GPS measurement using the difference between the actual and expected number of wave creasts observed as the change in signal delay. Thus it would seem it would suffer the exact same problem as a sophisticated position sampling approach.

Non-continuous errors might be different, e.g., multi-path effects, but these should result in greater Doppler velocity errors than positional errors (the position error shouldn't be at most approximately the distance of the receiver from the source of the reflection while the Doppler velocity measurement could be totally reversed).

Am I missing something?

Comment MMORPG revival (Score 4, Interesting) 106

As a former avid City of Heroes player, I wish that someone would do this for shuttered MMORPGs. There are so many, and unlike single-player games that will at least run on old hardware and/or OSes, shuttered MMORPGs are completely inaccessible by any means. (Well, other than server emulators, for the very, VERY few that are lucky enough to have them.)

A while back, I wrote an email to GoG basically telling them that I wish they'd consider approaching some of the publishers of shuttered MMORPGs and offering to host them, either buying the rights to the games outright or licensing them, and charging $10 or $15 per month for access to everything (or offer cheaper plans for limited access to one or some games). Because the playerbase of many of these games would be a lot smaller than the new flashy hotness MMORPGs, it probably wouldn't take that much in the way of hardware, and if they could negotiate access to the source code, they might even be able to rewrite parts of the game to run more efficiently or even release updates. I got back a response that boiled down to, "Thanks, but we're not going to do that."

I still think it's a market that's ripe, and someone at some point will exploit that and make a killing off of it.

Hmm... Anyone got some negotiating skills that could pair with my technical skills to get this done?

Comment Re:So which is it? (Score 1) 115

This is a quibble, but non-volatile RAM has only been the Holy Grail since about 1970. Prior to that, magnetic core memory was the standard RAM technology and is non-volatile. (To quibble the quibble, for a short period of time Williams tubes were the state-of-the-art (indeed, only) RAM, and they are volatile. Alan Turing played with Williams tubes.)

The first version always gets thrown away.