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Comment Re:This again? (Score 3, Informative) 480

Conservation of linear momentum is a mathematical consequence of translational symmetry - in other words, momentum is conserved if the laws of physics are invariant in space. Similarly, angular momentum is conserved if the laws of physics are invariant by rotation.

And energy is conserved if the system is invariant over a translation in time.

Hooray for Emmy Noether.

Comment Re:This again? (Score 5, Insightful) 480

This might be another Cold Fusion moment. Or, it might be the start of something very interesting.

When an experiment contradicts a theory, there are two possibilities: (1) there's something wrong with the experiment; or (2) there's something wrong with the theory. If the correct answer is (1), then it's par for the course: mistakes happen, and the process of science corrects them eventually. But if the correct answer is (2) then it's cork-popping time, because you have discovered new science.

Comment Re:Can't wait to get this installed in my house (Score 5, Informative) 514

https://www.we-energies.com/re...

Up to 17 cents cheaper per KWH (22c day, 5c night).

Assuming you blow 10kWh per day, primarily between 6am and 11pm, that's upwards of $2.20/day.

If you move your entire 10kWh load to the battery system and charge it over night, it drops you down to $0.50/day.

$1.70 savings per day. That's 2058 days to recoup the $3500 expenditure, or just a bit over 5 1/2 years. Over the ten year warranty period you'll save ~$3000, assuming electricity prices remain constant.

-Rick

Comment Re:Seems he has more of a clue (Score 1) 703

While you are facepalming you should wipe the egg off your face. And try googling for "USA oil production"

The US produced 3.1 billion barrels of oil last year.
http://www.eia.gov/dnav/pet/pe...

The US imported 3.3 billion barrels of oil last year.

So I guess my statement wasn't perfectly accurate as we don't produce more than 50% of our own oil, and a significant portion of what we do produce is distributed internationally.

Although, if you look at the trend, over the last 5 years we've reduced our oil imports by 900 million barrels a year while increasing our oil production by 1.2 billion barrels a year. At current rate by 2016 we will be producing more than we are importing.

So while I would admit to embellishing the statement a little, I think your dramatization is a bit much. ;)

-Rick

Comment Re:Seems he has more of a clue (Score 4, Informative) 703

"1) Fossil fuels are a limited supply. Maybe enough for another 50 years. Maybe 100. But still limited."

Matters on the type of fuel you're talking about. The US has coal reserves for hundreds of years. Even NG and Crude reserves to last a loooooong time, but they will continue to cost more and more to extract and refine.

"2) We purchase large amounts of oil from countries that, in general, do not like us."

We buy most of our oil, from ourselves. The vast majority of the rest is bought from Mexico and Canada. The largest of the insignificant provider nations is Venezuela. The amount of oil we buy from countries that, "Do not like us", is insignificant.

"3) If it were not for oil, our interest in the middle east would decline greatly, which would be a good thing."

Our interest in Middle Eastern oil is due to the lack of oil reserves in western Europe. Even without any US demand on Middle Eastern oil, the US will have a continued interest in the region until Western Europe transitions off of crude.

"More fuel efficiency and alternative fuels just simply make long term sense, even without considering climate change. So, what is the problem?"

This is really the crux of it. So let's say that the Pope/Scientists are wrong. There is no global warming and any investment in improving vehicle efficiency, air quality, and use of renewable is a waste of economic output. Well, we still get more efficient vehicles, better air quality, and a bunch of jobs. So, no big loss.

On the other hand, say the Pope/Scientists are right, but we do nothing. We are at risk of creating a catastrophic level event that would dramatically alter life on the planet, and could result in the death of billions of people.

So option A, we possibly lose a percent or two off of economic growth. Option B, we die, and the economy no longer matters.

As you said, "So, what is the problem?"

-Rick

Comment Re: The answer has been clear (Score 1) 390

Multiple IPs was one solution, but the other was much simpler.

The real address of the computer was its MAC, the prefix simply said how to get there. In the event of a failover, the client's computer would be notified the old prefix was now transitory and a new prefix was to be used for new connections.

At the last common router, the router would simply swap the transitory prefix for the new prefix. The packet would then go by the new path.

The server would multi-home for all prefixes it was assigned.

At both ends, the stack would handle all the detail, the applications never needed to know a thing. That's why nobody cared much about remembering IP addresses, because those weren't important except to the stack. You remembered the name and the address took care of itself.

One of the benefits was that this worked when switching ISPs. If you changed your provider, you could do so with no loss of connections and no loss of packets.

But the same was true of clients, as well. You could start a telnet session at home, move to a cyber cafe and finish up in a pub, all without breaking the connection, even if all three locations had different ISPs.

This would be great for students or staff at a university. And for the university. You don't need the network to be flat, you can remain on your Internet video session as your laptop leaps from access point to access point.

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