Well, as mentioned elsewhere, you're limited not just by the standard issues of solar cells, but also by more relevant entropy limits. If your solar cell is being hit by ambient radiated heat IR and is radiating IR in the same range, it's impossible to generate power without violating the laws of thermodynamics. Even though it's not technically a heat engine, you can treat a solar cell as an indirect heat engine subject to the limits of Carnot's theorum (as Carnot's theorum is simply a direct consequence of the limits of entropy between two temperature wells - if you can exceed it, you can create perpetual motion with an efficient heat pump that restores heat to the hot well).
Thankfully, the filament in incandescent bulbs is ~2750K, which means it's technically possible to get up to almost 90% efficiency without violating the laws of thermodynamics. Of course, real-world cells won't give you that, as you note. Not to mention that that assumes you're capturing all of the visible light, too!
Of course, it's all in the details, isn't it? At the very least, there's the question of how well cooled the sensor is to minimize heat noise, and beyond that, it could be something like an L3CCD, where you're literally counting every photon that hits the sensor. I have no idea what hardware they're actually using.
First Discovery program about the telescope: "First Light Gala: The Discovery Channel Telescope, From Inception To Completion" Second Discovery program about the telescope: "Aliens Above Us: The Discovery Channel Telescope Provides Proof Of Bigfoot's Ghost Piloting A UFO"
We'll just make a heat reservoir and hook it up to a heat pump that pumps in heat from outside with a COP of well-greater-than-1, and we'll surround the reservoir in highly efficient IR-absorbing panels, which will capture almost all of the energy, driving the heat pump and yielding energy to spare. Perpetual motion! Take that, laws of physics!
Whether you're dealing with a physical "engine" or not, Carnot must be obeyed, because if he's not, a high-COP heat pump can pump in more heat against the gradient than is needed to generate the power. So obviously there's going to be real limits on waste heat energy recovery using solar panels to absorb infrared, just like waste heat recovery using any mechanism.
In fact, the data that I've seen shows that one type of solar cell (CIGS) can actually *increase* in power output over time. Unlike with silicon cells, where there's a small (usually tapering off) loss over time, the "damage" from ionizing radiation can help remove defects in CIGS cells, functioning as a slow annealing stage.
Given that untinted window glass is in the 80-90% range, 70% isn't bad at all.
Remember that you don't perceive brightness linearly. Its several orders of magnitude brighter outside on a sunny day than it is in a very well-lit room inside, but it doesn't feel that way. Think of how many light bulbs you'd need to have to match 1000W/m^2, factoring in also that even fluorescent and LED bulbs lose the lion's share of their energy as heat.
It's actually a really fun contest to take part in, first selecting what bug or group of bugs you want to exploit, and then how you want to hide them. the contest last year was to make it so that if a baggage handler typed a special but inconspicuous comment on the bag, it'd reroute the bag to some mean location. My "bug" was that the user's comment was stored in a struct in a string of a specific length but there was no bounds checking, so their comment string could overwrite the destination (I made it look like there was bounds checking, but the code was broken). The destination was right after the comment string, so whatever three characters in the comment were immediately after the comment limit (which could just be in the middle of a word in an innocent-looking comment) became the destination airport code.
I think most people who carry OC for self defense specifically want to have it just to point it at someone if they get threatening. In particular, the case of a guy who won't take no for an answer. The envisioned scenario is, they point it, the guy decides it's not worth being blind and feeling like they're on fire for half an hour, and backs off. The trigger doesn't get pushed. I think a lot of people who carry it would actually have trouble pressing the trigger. I know I would.
Just like with guns, the trigger gets pulled sometimes. But the consequences of a pulled trigger are very different from with a gun. Even with asthmatics, papper spray alone is rarely sufficient to cause death; in the couple dozen documented cases of death, there were other contributing factors. A large minority of gunshots are fatal.
Likelihood is of course a critical factor. Because the negatives - accidental shootings, children getting ahold of the guns, people using the gun when drunk or angry when if it wasn't so available at that instant they wouldn't have, mistaken identity, etc - are very real, so the likelyhood of that has to be weighed against any potential benefit.
And yes, having 400 amateurs in a movie theater shooting in the dark, fog and chaos trying to hit some guy on the other side of the theater sounds a *lot* worse than the one guy shooting.
I'm not quite getting your post. You made the decision while being occupied? Really, that's what was on your mind, "what am I doing to do next time", rather than "what can I do to get out of this"?
While an insightful post, note that stranger things have happened. A lot of things can seem totally out of reach from practicality before a technological breakthrough or rapid series of continuous advances totally changes the picture.
Yeah, horns has singular/plural forms for the word "horn" (although it's strong neuter, so the nominative and accusative forms are identical between singular and plural except for umlaut-shifts, which there aren't any in "horn"). But Icelandic still has lots of mass nouns - for example, "fólk" (people), which is always singular, and the opposite case - for example, "skilaboð" (message), which is always plural. I'd say that something like 5% of words fit into one of those categories.
BTW, is it easy to tell noun gender in Finnish and Estonian? There can be clues in Icelandic, but they can often be contradictory and unreliable (for example, almost 2/3rds of nouns with a base -i ending are weak masculine but almost 1/3rd are strong neuter), and there's always exceptions - and on probably 1/3 to 1/2 of all nouns there's not any clues, you just have to learn it.
The concept of even needing to provide a reference to counter this is laughable, in that every serious dataset contradicts it. "Google" is a good enough reference here.
Uhhh... you. That's the fundamental point of the argument that "It's too hot now."
Funny, I don't remember saying that. Oh yeah, that's because you made it up. I said, "What matters is the *rate change*".
Would you rather A) be unarmed, or B) have a concealed pistol.
In short, would I want to spend every waking moment surrounded by people who are armed to the teeth for the highly unlikely offchance that I happen to be in a situation like this one at some point, and then hope that amateurs take him down without hitting even more innocent people in the smoke, darkness, and chaos?
I'll answer that with an unhesitating "no".
I'm not totally anti-self-defense-tools. For example, I think Iceland's anti-pepper-spray law goes too far, in that it's a pretty lousy weapon for committing crime with even compared with commonly available tools like a kitchen knife, and is pretty obviously only for self-defense, with non-lethal, non-permanent results. But do I want to live in a paranoia-society surrounded by heavily armed people at all times? No thank you!
I think it's safe to say that violence has always been with humanity since the origin of our species, and will continue to be with our species for the indefinite future. That said, do you really think he could have killed 12 and injured 50 had he burst into the theatre armed with a flint knife and an atlatl?
Weapons technology doesn't make people kill, but it sure as heck makes them a lot more proficient at it.
Not true. The world was on a cooling trend until the industrial revolution.
And the Earth has been far hotter on average than it is today
So? Who cares what the temperature was like at some arbitrary point in the distant past? Species change, ecosystems change. What matters is the *rate change*, because adaptation doesn't occur instantaneously. It's the rate change that's concerning. The last time Earth saw this sort of rate-change was the Paleocene-Eocene Thermal Maximum. The world was left as uch a different place that we call it a different era (the Eocene).
Dumb Aztecs. They should have learned that a cosmic Jewish Zombie who was his own father can make you live forever if you symbolically eat his flesh and telepathically tell him you accept him as your master, so he can remove an evil force from your soul that is present in humanity because a rib-woman was convinced by a talking snake to eat from a magical tree, and because of this, we need to spend our sundays going to a magic house where a priest transmutates crackers and grape juice with an incantation while we send psychic messages by holding our hands together, give the magic house our money, and we can be confident that global warming is either not real because after a guy built a huge zoo-boat, said Zombie-Dad promised the boat-guy that he wouldn't let the world be destroyed again - or, contrarily, that it doesn't matter, because the zombie is going to be imminently reanimated a second time and then everybody is going to die.
Slashdot Mirror
Well, as mentioned elsewhere, you're limited not just by the standard issues of solar cells, but also by more relevant entropy limits. If your solar cell is being hit by ambient radiated heat IR and is radiating IR in the same range, it's impossible to generate power without violating the laws of thermodynamics. Even though it's not technically a heat engine, you can treat a solar cell as an indirect heat engine subject to the limits of Carnot's theorum (as Carnot's theorum is simply a direct consequence of the limits of entropy between two temperature wells - if you can exceed it, you can create perpetual motion with an efficient heat pump that restores heat to the hot well).
Thankfully, the filament in incandescent bulbs is ~2750K, which means it's technically possible to get up to almost 90% efficiency without violating the laws of thermodynamics. Of course, real-world cells won't give you that, as you note. Not to mention that that assumes you're capturing all of the visible light, too!
Of course, it's all in the details, isn't it? At the very least, there's the question of how well cooled the sensor is to minimize heat noise, and beyond that, it could be something like an L3CCD, where you're literally counting every photon that hits the sensor. I have no idea what hardware they're actually using.
First Discovery program about the telescope: "First Light Gala: The Discovery Channel Telescope, From Inception To Completion"
Second Discovery program about the telescope: "Aliens Above Us: The Discovery Channel Telescope Provides Proof Of Bigfoot's Ghost Piloting A UFO"
We'll just make a heat reservoir and hook it up to a heat pump that pumps in heat from outside with a COP of well-greater-than-1, and we'll surround the reservoir in highly efficient IR-absorbing panels, which will capture almost all of the energy, driving the heat pump and yielding energy to spare. Perpetual motion! Take that, laws of physics!
Whether you're dealing with a physical "engine" or not, Carnot must be obeyed, because if he's not, a high-COP heat pump can pump in more heat against the gradient than is needed to generate the power. So obviously there's going to be real limits on waste heat energy recovery using solar panels to absorb infrared, just like waste heat recovery using any mechanism.
In fact, the data that I've seen shows that one type of solar cell (CIGS) can actually *increase* in power output over time. Unlike with silicon cells, where there's a small (usually tapering off) loss over time, the "damage" from ionizing radiation can help remove defects in CIGS cells, functioning as a slow annealing stage.
Given that untinted window glass is in the 80-90% range, 70% isn't bad at all.
Remember that you don't perceive brightness linearly. Its several orders of magnitude brighter outside on a sunny day than it is in a very well-lit room inside, but it doesn't feel that way. Think of how many light bulbs you'd need to have to match 1000W/m^2, factoring in also that even fluorescent and LED bulbs lose the lion's share of their energy as heat.
Hehehe, you got me ;)
It's actually a really fun contest to take part in, first selecting what bug or group of bugs you want to exploit, and then how you want to hide them. the contest last year was to make it so that if a baggage handler typed a special but inconspicuous comment on the bag, it'd reroute the bag to some mean location. My "bug" was that the user's comment was stored in a struct in a string of a specific length but there was no bounds checking, so their comment string could overwrite the destination (I made it look like there was bounds checking, but the code was broken). The destination was right after the comment string, so whatever three characters in the comment were immediately after the comment limit (which could just be in the middle of a word in an innocent-looking comment) became the destination airport code.
Along the lines of the grammatically-correct sentence "Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo".
...coming back? Just my luck that the first year I entered it, it died... :P
Exactly. Automatic weapons are tools designed specifically to be good at killing people. Cars are not.
Hahaha, that's great ;)
I think most people who carry OC for self defense specifically want to have it just to point it at someone if they get threatening. In particular, the case of a guy who won't take no for an answer. The envisioned scenario is, they point it, the guy decides it's not worth being blind and feeling like they're on fire for half an hour, and backs off. The trigger doesn't get pushed. I think a lot of people who carry it would actually have trouble pressing the trigger. I know I would.
Just like with guns, the trigger gets pulled sometimes. But the consequences of a pulled trigger are very different from with a gun. Even with asthmatics, papper spray alone is rarely sufficient to cause death; in the couple dozen documented cases of death, there were other contributing factors. A large minority of gunshots are fatal.
Likelihood is of course a critical factor. Because the negatives - accidental shootings, children getting ahold of the guns, people using the gun when drunk or angry when if it wasn't so available at that instant they wouldn't have, mistaken identity, etc - are very real, so the likelyhood of that has to be weighed against any potential benefit.
And yes, having 400 amateurs in a movie theater shooting in the dark, fog and chaos trying to hit some guy on the other side of the theater sounds a *lot* worse than the one guy shooting.
I'm not quite getting your post. You made the decision while being occupied? Really, that's what was on your mind, "what am I doing to do next time", rather than "what can I do to get out of this"?
While an insightful post, note that stranger things have happened. A lot of things can seem totally out of reach from practicality before a technological breakthrough or rapid series of continuous advances totally changes the picture.
Yeah, horns has singular/plural forms for the word "horn" (although it's strong neuter, so the nominative and accusative forms are identical between singular and plural except for umlaut-shifts, which there aren't any in "horn"). But Icelandic still has lots of mass nouns - for example, "fólk" (people), which is always singular, and the opposite case - for example, "skilaboð" (message), which is always plural. I'd say that something like 5% of words fit into one of those categories.
BTW, is it easy to tell noun gender in Finnish and Estonian? There can be clues in Icelandic, but they can often be contradictory and unreliable (for example, almost 2/3rds of nouns with a base -i ending are weak masculine but almost 1/3rd are strong neuter), and there's always exceptions - and on probably 1/3 to 1/2 of all nouns there's not any clues, you just have to learn it.
The concept of even needing to provide a reference to counter this is laughable, in that every serious dataset contradicts it. "Google" is a good enough reference here.
Funny, I don't remember saying that. Oh yeah, that's because you made it up. I said, "What matters is the *rate change*".
I grew up there, thanks.
FYI, I'm a rape victim too, and wanted to buy pepper spray after I found myself freaking out in certain situations.
In short, would I want to spend every waking moment surrounded by people who are armed to the teeth for the highly unlikely offchance that I happen to be in a situation like this one at some point, and then hope that amateurs take him down without hitting even more innocent people in the smoke, darkness, and chaos?
I'll answer that with an unhesitating "no".
I'm not totally anti-self-defense-tools. For example, I think Iceland's anti-pepper-spray law goes too far, in that it's a pretty lousy weapon for committing crime with even compared with commonly available tools like a kitchen knife, and is pretty obviously only for self-defense, with non-lethal, non-permanent results. But do I want to live in a paranoia-society surrounded by heavily armed people at all times? No thank you!
Are you really defending talking snakes?
Stupid government, always trying to take away my Doomsday devices... Oh yes they'll rue the day...
I think it's safe to say that violence has always been with humanity since the origin of our species, and will continue to be with our species for the indefinite future. That said, do you really think he could have killed 12 and injured 50 had he burst into the theatre armed with a flint knife and an atlatl?
Weapons technology doesn't make people kill, but it sure as heck makes them a lot more proficient at it.
Not true. The world was on a cooling trend until the industrial revolution.
So? Who cares what the temperature was like at some arbitrary point in the distant past? Species change, ecosystems change. What matters is the *rate change*, because adaptation doesn't occur instantaneously. It's the rate change that's concerning. The last time Earth saw this sort of rate-change was the Paleocene-Eocene Thermal Maximum. The world was left as uch a different place that we call it a different era (the Eocene).
Dumb Aztecs. They should have learned that a cosmic Jewish Zombie who was his own father can make you live forever if you symbolically eat his flesh and telepathically tell him you accept him as your master, so he can remove an evil force from your soul that is present in humanity because a rib-woman was convinced by a talking snake to eat from a magical tree, and because of this, we need to spend our sundays going to a magic house where a priest transmutates crackers and grape juice with an incantation while we send psychic messages by holding our hands together, give the magic house our money, and we can be confident that global warming is either not real because after a guy built a huge zoo-boat, said Zombie-Dad promised the boat-guy that he wouldn't let the world be destroyed again - or, contrarily, that it doesn't matter, because the zombie is going to be imminently reanimated a second time and then everybody is going to die.
It's much more rational that way.