If the aliens are about as lucky as we are with nuclear power, isotope analysis of their atmosphere might indicate that they were experimenting with nuclear fission at some point in the last couple of million years.
Dilbert is a corporate tool intended to placate all of the cubicle-drones because they can have a chuckle and identify with him and think "well, gosh, things aren't so bad!"
What company are you referring to and where do I send my resume?
Or do you just assume that real-life engineering jobs must be better than what's depicted in Dilbert? I'm sorry.
> Anyway, no, goggles won't save you. If it's white light, you can't filter a narrow band like laser goggles.
Exactly. Also, using white, noncoherent light makes this thing much less likely to cause permanent damage than a laser. The monochromatic, coherent light of the latter is focused on much smaller spots on the retina.
Modern Advanced Heavy Water reactors are essentially immune from such accidents,
No, they're not at all immune to meltdown from decay heat.
Stopping the fission reaction worked just fine in Japan, but doing that alone does nothing about all the MW of decay heat that cannot be shut off by any process known to man - the fuel rods have to be cooled for days or weeks.
Any modern design should be designed with the question of "What happens if you cut the main coolant feed line and turn off all power (including emergency power) to the reactor?" in mind. Even in this scenario, the radioactive mess should be confined to the interior of the reactor building.
That doesn't explain why it wasn't designed to replace generators or provide alternative power sources quickly. It amazes me that it took so many days to solve it, and they needed to install a new 1.5 kilometers long cable.
Remember the 8.9 earthquake and the tsunami? Things like that can really mess up your reactor-saving efforts.
Next step is: Put them as high as possible, so no water can reach them.
It's like with data backups: If you make three backups and put them all in the same place, they'll all be gone if that place burns down. Instead, make three backups and put them in different places.
I find no evidence that these "disasters just keep on killing."
That's because the studies aren't sensitive enough and don't include sufficient population. Chernobyl basically affected a few hundred million people all over Europe. Are these studies sensitive enough to pick up small increases in cancer rates, e.g. a dozen additional cases per year in a population of half a billion people? I don't think so.
If Chernobyl didn't do much, why are we still checking wild boar meat for contamination decades after the accident, and why do we still find boars that need to be disposed?
The Fukushima series of explosions was possibly caused by the Stuxnet malware, which prevented the proper working of Siemens Simatic-controlled backup systems that were activated in the aftermath of the earthquake and tsunami to continue to cool the emergency-scrammed reactors.
Right, because a reactor designed by GE will include control systems from their fiercest competitor, Siemens.
GE management would probably rather have a fuel rod for breakfast and wash it down with coffee brewed with reactor coolant before that happens.
how about having a huge chlorine bath under the sodium reactor,
Great idea. Let's build a huge potential bomb by placing a metal that reacts violently with pretty much anything else next to the substance that it reacts most violently with.
and if there's a reactor problem the barrier dividing the two is lowered resulting in radioactive NaCl being created?
The reaction between chlorine and sodium is hugely exothermic. What you propose basically amounts to blowing the reactor and its contents sky-high.
Also, you don't want chlorine anywhere near neutron radiation, since the Cl-36 created that way has a half-life of a few hundred thousand years. Short enough to make it a radiation hazard, and yet long enough to make disposal quite difficult.
What I don't understand is why the spent fuel ponds are on top of the reactor.
Spent fuel rods are intensely radioactive - enough that merely being a few seconds in their vicinity will give people doses in the range of a few Sieverts (i.e. deadly within a few days). Hence you want to take them out of the reactor remotely and immediately cover them with water again, without having to move them all over the place.
Also, the rods still produce quite a bit of heat, which is another reason why they need to be submerged as soon as possible after removing them from the reactor.
The first is a bunch of control rods positioned above the reactor and held in place by an electromagnet. If the power fails, the magnet stops working and gravity drops the rods into the core.
Most current reactors have ways of shutting down the chain reaction if power fails. I'd wager that using liquid nitrogen to push the control rods into the core is even better than using gravity, since that way you can force the control rods into the core even if it has already begun to deform, warp or melt.
However, all of these measures do exactly nothing against decay heat. You cannot turn off decay heat in any way - if you don't cool the part of the reactor that contains the fission products, it will happily heat up to temperatures that will melt or otherwise destroy pretty much any material known to man.
Great for atomic bombs, and if you don't want to develop the technology, it's still an extremely powerful chemical poison.
The chemical toxicity of plutonium is pretty much irrelevant compared to its radiotoxicity. If you're looking to poison something with a heavy metal, pretty much any other heavy metal will do the job as well as plutonium while being much, much easier to acquire and handle.
Also, "extremely powerful" chemical poisons are about one thousand times as toxic as plutonium. Truly extremely powerful chemical poisons are about one hundred thousand times as toxic as plutonium. A few ten nanograms of plutonium will make a person develop cancer within a few years, a few ten nanograms of botulinum toxin will make sure that the person doesn't get a chance to develop cancer in ten years.
Its reaction has a negative temperature coefficient, meaning that the reaction self-moderates if it gets too hot, rather than requiring an external control system to prevent meltdown.
News flash: Most light water reactors have a negative temperature coefficient, too. However, negative temperature coefficient don't do anything at all about decay heat after the reactor is shut down, because there's no more chain reaction after shutdown.
Decay heat alone is enough to cause a meltdown, and the only way to deal with decay heat is to cool the thing until heat generation has decayed below the level where it will melt the fuel rods, fuel pebbles, reactor walls, etc.
Since a CANDU (Heavy Water) reactor's fuel isn't naturally capable of going critical, couldn't that existing, tried and true design be used instead?
CANDU reactors will produce just the same problems as the light water reactors in Japan if you turn off all power to them.
Also, CANDU reactors can produce weapons-grade plutonium much more easily than the designed used in Japan.
Technically they're wrong.
Republic means that the title of head honcho isn't hereditary, but determined by other means (e.g. fist fight, elections, drawing lots, etc).
Democracy means that people get to vote on stuff. Depending on what stuff is, democracy can be direct (people vote on bills) or indirect (people vote for representatives, which then vote on bills).
... but his reasoning skills are not. Otherwise, he wouldn't prove a statement ("Everyone can train their memory to the level of a champion") with a sample size of one ("I trained my memory to the level of a champion").
There should be a name for this. Hm. The "I can do it so everyone can do it"-fallacy?
So this means if a planet orbits a sun in any other plane than the one that happens to line up directly with us, it wont spot anything? Wouldn't that be...most of space?
Most of space is actually empty.
But yes, only a tiny fraction of all stars will have transiting plantes. Kepler makes up for that by looking at lots of start simultaneously. Even if only 0.5% of all stars have transiting planets, you're still likely to find quite a few if you look at thousands of stars.
That's only a concern for the military. Just like using tear gas is a no-no in a war (OMFG chemical weapon!), while it's perfectly fine for use by police on unruly citizens.
If I want working, bug-free and maintainable code, I hire a programmer. Heck, if the programmer is good enough, it might even be worth it to hire a typist for him to dictate his code to.
Seriously... expecting a programmer to hit 150 WPM is like expecting your carpenter to be the world champion in tree cutting.
The Kinect is the first device, at least the first consumer one, that can do a good job of tracking what it happening completely visually and passively. You don't have to hold anything or have anything on you (like a reflective strip). It just watches what you do and can get useful 3D data from that, which can then be processed by programs. That's pretty amazing.
The luddite in me wonders if you can use Kinect to create a battery-free wireless mouse by pointing the camera at the mousepad and using an old optical mouse with the cable removed to simulate the look and feel of an actual mouse to the user?
Slashdot Mirror
If the aliens are about as lucky as we are with nuclear power, isotope analysis of their atmosphere might indicate that they were experimenting with nuclear fission at some point in the last couple of million years.
What company are you referring to and where do I send my resume?
Or do you just assume that real-life engineering jobs must be better than what's depicted in Dilbert? I'm sorry.
> Anyway, no, goggles won't save you. If it's white light, you can't filter a narrow band like laser goggles. Exactly. Also, using white, noncoherent light makes this thing much less likely to cause permanent damage than a laser. The monochromatic, coherent light of the latter is focused on much smaller spots on the retina.
No, they're not at all immune to meltdown from decay heat.
Stopping the fission reaction worked just fine in Japan, but doing that alone does nothing about all the MW of decay heat that cannot be shut off by any process known to man - the fuel rods have to be cooled for days or weeks.
Any modern design should be designed with the question of "What happens if you cut the main coolant feed line and turn off all power (including emergency power) to the reactor?" in mind. Even in this scenario, the radioactive mess should be confined to the interior of the reactor building.
Yes, but they can still only burn the 0.7% U-235 in natural uranium ... and they create plutonium from the U-238.
On the other hand, natural thorium is pretty much 100% Th-232.
Remember the 8.9 earthquake and the tsunami? Things like that can really mess up your reactor-saving efforts.
It's like with data backups: If you make three backups and put them all in the same place, they'll all be gone if that place burns down. Instead, make three backups and put them in different places.
Kyshtym isn't on that list?
http://en.wikipedia.org/wiki/Kyshtym_disaster
I find no evidence that these "disasters just keep on killing."
That's because the studies aren't sensitive enough and don't include sufficient population. Chernobyl basically affected a few hundred million people all over Europe. Are these studies sensitive enough to pick up small increases in cancer rates, e.g. a dozen additional cases per year in a population of half a billion people? I don't think so.
If Chernobyl didn't do much, why are we still checking wild boar meat for contamination decades after the accident, and why do we still find boars that need to be disposed?
I believe they use high-temperature sodium-sulfur batteries.
Right, because a reactor designed by GE will include control systems from their fiercest competitor, Siemens.
GE management would probably rather have a fuel rod for breakfast and wash it down with coffee brewed with reactor coolant before that happens.
Got any other good jokes?
Hydroelectric power disasters stop killing people a few days after the disaster. Nuclear power disasters just keep on killing for centuries or longer.
Great idea. Let's build a huge potential bomb by placing a metal that reacts violently with pretty much anything else next to the substance that it reacts most violently with.
and if there's a reactor problem the barrier dividing the two is lowered resulting in radioactive NaCl being created?
The reaction between chlorine and sodium is hugely exothermic. What you propose basically amounts to blowing the reactor and its contents sky-high.
Also, you don't want chlorine anywhere near neutron radiation, since the Cl-36 created that way has a half-life of a few hundred thousand years. Short enough to make it a radiation hazard, and yet long enough to make disposal quite difficult.
And then it melts to slag, since decay heat doesn't care about criticality or lack thereof.
Spent fuel rods are intensely radioactive - enough that merely being a few seconds in their vicinity will give people doses in the range of a few Sieverts (i.e. deadly within a few days). Hence you want to take them out of the reactor remotely and immediately cover them with water again, without having to move them all over the place.
Also, the rods still produce quite a bit of heat, which is another reason why they need to be submerged as soon as possible after removing them from the reactor.
Most current reactors have ways of shutting down the chain reaction if power fails. I'd wager that using liquid nitrogen to push the control rods into the core is even better than using gravity, since that way you can force the control rods into the core even if it has already begun to deform, warp or melt.
However, all of these measures do exactly nothing against decay heat. You cannot turn off decay heat in any way - if you don't cool the part of the reactor that contains the fission products, it will happily heat up to temperatures that will melt or otherwise destroy pretty much any material known to man.
The chemical toxicity of plutonium is pretty much irrelevant compared to its radiotoxicity. If you're looking to poison something with a heavy metal, pretty much any other heavy metal will do the job as well as plutonium while being much, much easier to acquire and handle.
Also, "extremely powerful" chemical poisons are about one thousand times as toxic as plutonium. Truly extremely powerful chemical poisons are about one hundred thousand times as toxic as plutonium. A few ten nanograms of plutonium will make a person develop cancer within a few years, a few ten nanograms of botulinum toxin will make sure that the person doesn't get a chance to develop cancer in ten years.
News flash: Most light water reactors have a negative temperature coefficient, too. However, negative temperature coefficient don't do anything at all about decay heat after the reactor is shut down, because there's no more chain reaction after shutdown.
Decay heat alone is enough to cause a meltdown, and the only way to deal with decay heat is to cool the thing until heat generation has decayed below the level where it will melt the fuel rods, fuel pebbles, reactor walls, etc.
Since a CANDU (Heavy Water) reactor's fuel isn't naturally capable of going critical, couldn't that existing, tried and true design be used instead? CANDU reactors will produce just the same problems as the light water reactors in Japan if you turn off all power to them.
Also, CANDU reactors can produce weapons-grade plutonium much more easily than the designed used in Japan.
Technically they're wrong. Republic means that the title of head honcho isn't hereditary, but determined by other means (e.g. fist fight, elections, drawing lots, etc). Democracy means that people get to vote on stuff. Depending on what stuff is, democracy can be direct (people vote on bills) or indirect (people vote for representatives, which then vote on bills).
... but his reasoning skills are not. Otherwise, he wouldn't prove a statement ("Everyone can train their memory to the level of a champion") with a sample size of one ("I trained my memory to the level of a champion"). There should be a name for this. Hm. The "I can do it so everyone can do it"-fallacy?
Incoming in 3 ... 2 ...
Most of space is actually empty.
But yes, only a tiny fraction of all stars will have transiting plantes. Kepler makes up for that by looking at lots of start simultaneously. Even if only 0.5% of all stars have transiting planets, you're still likely to find quite a few if you look at thousands of stars.
That's only a concern for the military. Just like using tear gas is a no-no in a war (OMFG chemical weapon!), while it's perfectly fine for use by police on unruly citizens.
If I want working, bug-free and maintainable code, I hire a programmer. Heck, if the programmer is good enough, it might even be worth it to hire a typist for him to dictate his code to.
Seriously ... expecting a programmer to hit 150 WPM is like expecting your carpenter to be the world champion in tree cutting.
The luddite in me wonders if you can use Kinect to create a battery-free wireless mouse by pointing the camera at the mousepad and using an old optical mouse with the cable removed to simulate the look and feel of an actual mouse to the user?