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Comments

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MIT Designs Tsunami Proof Floating Nuclear Reactor

Neil Boekend Re:Does the name 'Titanic' ring any bells? (217 comments)

We can make unsinkable objects. The problems with the Titanic were mostly because the designers were incapable of modeling the behavior correctly because they had no computers and human calculations powering a finite element method is expensive to say the least. It had been done for at least one project, the Afsluitdijk in the Netherlands, but against extreme cost.
Nowadays we have computers that can model such a problem with an accuracy those designers could only dream of.
Also, we learned that watertight bulkheads should end significantly above the water level, so that tipping doesn't get the tops below water level. Oops.

5 days ago
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MIT Designs Tsunami Proof Floating Nuclear Reactor

Neil Boekend Re:man them (217 comments)

No they don't.
The shielding on any fission reactor is so massive that a normal torpedo won't hurt it. A nuclear torpedo would, but in that case the area is screwed anyway.

Chances are that even a nuclear bomb isn't going to cause much extra fission in the reactor fuel.
The neutron pulse from it travels at 14000 km/sec. That is way faster than the shockwave that damages the shielding. So the reactor shielding is still there to absorb much of the neutron pulse.
If the neutrons from the bomb are not inducing much extra fission in the reactor fuel the radiation from that fuel isn't going to make a difference in that mess of radioactive isotopes that is caused in the water.
Warning: "much extra fission" is relative to the frakkin' nuclear bomb that starts the whole mess.

That isn't to say its by definition a good idea to place a nuclear reactor on an oil rig-like structure.
What we need is modeling of worst case scenarios. Model the flow patterns of the fuel broken up into little fragments without containment during both still weather and the largest storm ever seen times 2. What are the dosages in the few square km around the site?
Maybe everything sinks to the bottom, where it's really harmless, oil floats, which makes it dangerous. The ocean floor is usually empty, so a couple of kg of uranium isn't going to do much.
Does uranium dissolve in seawater? How much of the fission chain dissolves in seawater?

5 days ago
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'Thermoelectrics' Could One Day Power Cars

Neil Boekend Not usefull for waste heat (174 comments)

Waste heat is often a lot and usually needs to be moved away fast.
If you let the heatflow of a car pass through these tiles you's need a lot more surface area to get sufficient heat out of the engine.
If you try to cool a CPU through these things the CPU will overheat quite soon.
These things have "Ultralow thermal conductivity" according to the article. That means they act as thermal insulators. Not what you want when using waste heat.
This is useful for other places.
1. Places where you can replace insulation. A house has too low delta T, but I could imagine the inside of the burn chamber of a central heating installation.
2. Places where heat is generated for the specific purpose of powering these thermoelectric tiles. Then you have less losses from normal thermal conductivity.

about a week ago
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Lack of US Cybersecurity Across the Electric Grid

Neil Boekend Re:Low hanging fruit (95 comments)

A blown transformer can be replaced. No problem. 2000 blown transformers including the one that powers the transformer factory is a whole other matter. It would probably take years to get the system back up.

Lightning protection doesn't work as well as it seems. Lightning protection is based on short high voltage high current spikes that blow the transformer in a fraction of a second.
The low voltage "fry a transformer in an hour" DC currents a CME would inject in the system are a different matter entirely. Sure, if the cable is decoupled on both ends the voltage will rise to above the lightning arrester's breakthrough voltage and just arc the energy away but that doesn't work if the cable is not decoupled.
Currently decoupling the cables is a manual job that can not be done for all transformers in the country in the 3 days of heads up a CME gives us.

about a week ago
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Student Records Kids Who Bully Him, Then Gets Threatened With Wiretapping Charge

Neil Boekend Re:Rewarding the bullies... (796 comments)

Streisand effect.

about a week ago
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Lack of US Cybersecurity Across the Electric Grid

Neil Boekend Re:Low hanging fruit (95 comments)

Solar flares aren't exactly FUD.
A big CME that hits earth will take out the electrical grid on the side of the planet it hits.
Problem is, it would be unaffordable to prepare for the energy that would dump into the net. The currents would be massive and unlike lightning strikes a higher placed cable isn't going to fix it. You'd need to do something like equipping all masts with a lightning arrester AND make it possible to physically short the in- and outputs for all transformers. Then the amount of igniting/exploding transformers might be manageable.

about a week ago
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Google Looked Into Space Elevator, Hoverboards, and Teleportation

Neil Boekend Re:Effectiveness of a space elevator. (98 comments)

1 km per day means the cargo will be highly irradiated by the Van Allen radiation belts.
Quite unsuitable for human transport.

about a week ago
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First Glow-In-the-Dark Road Debuts In Netherlands

Neil Boekend Re:you're kidding me, right? (187 comments)

1. This isn't the first test. Labtests have been done extensively.
2. It's 500 meters. Not miles. Not even 1 mile.

about a week ago
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First Glow-In-the-Dark Road Debuts In Netherlands

Neil Boekend Re:Weather (187 comments)

That once a year that snow covers the road and the cleanup crews haven't been fast enough so it actually stays there (instead of turning into salt water) we drive a lot slower. Slower means you don't have to see as far ahead because you have more time to respond. It means the regular headlights are more effective.

about a week ago
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First Glow-In-the-Dark Road Debuts In Netherlands

Neil Boekend Re:Just use headlights (187 comments)

HID lamps should be illegal and the legislators who pushed for their legality should be arrested. Those damn things are dangerously blinding.

about a week ago
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First Glow-In-the-Dark Road Debuts In Netherlands

Neil Boekend Re:Video of the road (187 comments)

A tiny bit of electricity times 135.470 km of public roads is a lot of electricity.
(disclaimer: that doesn't mean it's a bad idea)

about a week ago
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First Glow-In-the-Dark Road Debuts In Netherlands

Neil Boekend Re:Useless (187 comments)

Apart from that, especially women don't feel comfortable going around in dark places where they perceive that there can be rapists hiding in the dark.

Instead they prefer to so be blinded by streetlights that they can't see the rapist hiding a few meters beside the light spot.
People are counterproductive at times. Streetlight makes most of us feel safe, besides the simple fact that they decrease safety in most cases.

about a week ago
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Using Supercomputers To Predict Signs of Black Holes Swallowing Stars

Neil Boekend Re:Impossible (31 comments)

Correct me if I am wrong, but my limited knowledge of what happens tells me this:
Probably, assuming the observer is infinitely strong and can survive the gravity shear and immense pressure of the black hole:
From the observers POV the universe speeds up, until the surroundings (except for the black hole itself) become a bright light, because time dilation causes the cosmic background radiation to appear like visible light.
Then the black hole evaporates due to Hawking radiation and the observer is free again. When checking an outside ("absolute") clock billions of years have passed but the observer only felt a relative short while. The observer never encountered anything that could be considered a black hole. Time dilation reached near infinite before it could get there. The observer did encounter a lot of mass, mass that was falling into the black hole, never reaching it because time dilation didn't allow it to reach anything.
This mass has unknown properties. It is far denser than neutronium. It is still falling towards the core, only slowed down by time dilation.
The star itself was torn apart way before the "visible cosmic background" part. It kept falling towards the black hole as part of that mass with unknown properties.

From the outside an object doesn't exactly fall into the event horizon. It falls towards it but slows down before it. The light reflected or emitted by the object gets redshifted to nothingness. The event horizon does grow to meet the object.
Assuming the event horizon doesn't grow extremely fast the object will be invisible due to extreme redshift. Whether it is torn apart by gravity shear before that depends on the mass of the black hole and the strength of the object.

about a week ago
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UN: Renewables, Nuclear Must Triple To Save Climate

Neil Boekend Re:NIMBY rules (432 comments)

Anyone caught on the construction site will be shot for for trespassing in a secure location.

In that case I wouldn't want to be a construction worker there!

about two weeks ago
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UN: Renewables, Nuclear Must Triple To Save Climate

Neil Boekend Re:Nuclear is obvious, an energy surplus is desire (432 comments)

Air filtration, chemicals for narcose/desinfectant/pre and post op medicine, a couple of people busy, hospital heating.
A sex change operation is quite expensive, even just energy wise. It may cost more to change from female to male than there can be saved.
Especially since adding those parts may not change a woman from semi coldblooded to warmblooded.

Although, if every woman did that the energy consumption would dropping quite far in a hundred years.

Oh and GPP probably meant whenever reasonably possible.

about two weeks ago
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UN: Renewables, Nuclear Must Triple To Save Climate

Neil Boekend Re:Adding yet another box (432 comments)

If the xbox would have been standby anyway then it doesn't matter. It's even unwise to add an appleTV's standby to it since however little that may be it's fully wasted.

about two weeks ago
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Navy Debuts New Railgun That Launches Shells at Mach 7

Neil Boekend Re:Difficult to defend against (630 comments)

If stuff like forcefields are allowed then you should just give your ship a General Products hull.

about two weeks ago
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Navy Debuts New Railgun That Launches Shells at Mach 7

Neil Boekend Re:Am i the only one? (630 comments)

Well, you could end each conflict by lobbing a few ICBM's at the enemy. That'd stop them for sure.

These weapons are an alternative to lobbing nukes. A nicer alternative, something akin to the difference between removing a tumor with a scalpel or with a sledgehammer. Neither is fun for the tumor, but the surrounding tissue prefers the scalpel.

about two weeks ago

Submissions

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Google privacy policy change

Neil Boekend Neil Boekend writes  |  more than 2 years ago

Neil Boekend (1854906) writes "Dear Google user,
We're getting rid of over 60 different privacy policies across Google and replacing them with one that's a lot shorter and easier to read. Our new policy covers multiple products and features, reflecting our desire to create one beautifully simple and intuitive experience across Google.
We believe this stuff matters, so please take a few minutes to read our updated Privacy Policy and Terms of Service at http://www.google.com/policies. These changes will take effect on March 1, 2012."

Link to Original Source

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