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Comment: Re:Does the name 'Titanic' ring any bells? (Score 1) 217

by Neil Boekend (#46785749) Attached to: MIT Designs Tsunami Proof Floating Nuclear Reactor

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.

Comment: Re:man them (Score 1) 217

by Neil Boekend (#46785731) Attached to: MIT Designs Tsunami Proof Floating Nuclear Reactor

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?

Comment: Not usefull for waste heat (Score 1) 174

by Neil Boekend (#46777877) Attached to: 'Thermoelectrics' Could One Day Power Cars

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.

Comment: Re:Low hanging fruit (Score 1) 95

by Neil Boekend (#46777515) Attached to: Lack of US Cybersecurity Across the Electric Grid

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.

Comment: Re:Low hanging fruit (Score 1) 95

by Neil Boekend (#46766203) Attached to: Lack of US Cybersecurity Across the Electric Grid

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.

Comment: Re:Weather (Score 1) 187

by Neil Boekend (#46754493) Attached to: First Glow-In-the-Dark Road Debuts In Netherlands

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.

Comment: Re:Useless (Score 1) 187

by Neil Boekend (#46754345) Attached to: First Glow-In-the-Dark Road Debuts In Netherlands

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.

Comment: Re:Impossible (Score 2) 31

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.

"The medium is the message." -- Marshall McLuhan

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