You can usually go to eBay and find hundreds of high-intensity LED lots (usually of 50 or 100) for sale from various sellers in Hong Kong (find someone with a low combined bid price and shipping). For Joe Hobbyist, it's usually much cheaper than ordering it from most of the component suppliers out there.
The DOE agrees with you! (That's a picture of Solar One, a pilot solar power project in the Mojave 20-odd years ago; I think it's actually being used as part of California's power grid now)
Check out Wikipedia's article on solar power for heliostats (the tracking mirrors) and various other arrangements that are used in similar solar thermal plants (or death rays!)
Sorry, I didn't mean to condescend. If you're still reading, only the parabola has a point focus where any incoming ray of light that's parallel to the latus rectum (see, it's a learning experience for me too!) ends up at the focus. Almost everything else is subject to something similar to spherical aberration where the focus is smeared out. Like you say, it doesn't have to be a parabola to work, but it's probably the most efficient (in terms of number of people with mirrors, anyway)
One of the definitions of a parabola (the one I got when I was in high school anyways) is that it's the collection of points equidistant (the same distance) from a point, the focus, and a line, the directrix. One of the side notes of this is that the lines coming from the directrix are all at right angles to the directrix. So basically, if you have nicely collimated (made up of all parallel rays--a good assumption given that we're however many millions of miles away from the sun) and they're all coming in at right angles to the parabola's directrix (this is where the aiming comes into play) all the incoming rays of light will be aimed directly at the focus of the parabola. By widening or narrowing your parabola (making sure that it is still, in fact, a parabola) you can change your focal length (how far out you shoot).
Since a picture is worth a 1000 words, check out the second image at Mathworld's article.
No, Jon Bardeen, Walter Brattain and William Shockley invented the bipolar junction transistor, though Shockley was dropped from the patent because his ideas were too close to the field effect transistor which had earlier been patented (and which he later succeeded in actually building).
Jack Kilby at Texas Instruments succeeded in inventing the integrated circuit. Robert Noyce of Fairchild Semiconductor was also awarded a patent for an integrated circuit six months later (the two are credited as being the co-inventors of the integrated circuit) and ultimately, it was his planar design process that was the basis for most future integrated circuits)
"[...] duckspeak, to quack like a duck. It is one of those interesting words that have two contradictory meanings. Applied to an opponent, it is abuse, applied to someone you agree with, it is praise."
It was a remark made in jest, like (I thought) most of the "xxx, is that you?" memes. While I probably should have qualified that initially, I didn't mean to suggest that you were an eco-terrorist, or wished for the wholesale destruction of human kind.
FWIW, I do agree with some of your sentiments; we need to be a warden to what little (in many places) remains of our environment. Headlong destruction of natural habitats and countless species of plants/animals/etc. can only lead to (or has already led to) trouble.
(For those who didn't have a misspent childhood reading comic books, Ra's al Ghul is the eco-terrorist supervillain in Batman who seeks "balance" between man and nature, usually involving the extermination of the former)
The Amish (and I believe to a lesser extent, Mennonites in general) believe that you have to make a conscious and informed decision to be baptised and formally join their faith, so Rumspringa lets them have a taste of life on the outside. The majority usually decide to stay, but UPN had a reality TV show Amish in the City and for some reason, the four Amish that were featured all decided to leave the community. Probably had something to do with the fact that they put them up with a bunch of "English" in a big mansion, and got them doing various activities together.
Not to ruin a perfectly good joke, but for whatever reason, the Amish seem pretty gung-ho for biotechnology and what not (at least in their embrace of GM crops and what not). Another reason may be the fact that the Amish also all descended from a few hundred Swiss Germans (who did and continue to marry within themselves) so they suffer from the founder effect.
According to the wikipedia article on the Amish, there was a 60 Minutes piece some time ago about a clinic the Amish themselves set up in Ohio in order to investigate Amish-only genetic diseases (including one that caused severe mental retardation and various other maladies).
You may think this to be evidence of the waste that is NASA, but there are many more who would say that this is a shining example of the return reaped from the investment in NASA and in science as a whole. DISCLAIMER: I won't claim to be one since I'm not an american and don't directly contribute to funding either of these.
This is probably what our own solar system looked like some 5 billion years ago, and probably how our own planet came to be. And now we can actually see it. That's powerful (to me anyways). I choose to believe that the fact that this is happening in our own backyard (galactically speaking), and around a star very much like our own may mean that we're not alone in this universe.
Sure, there's a lot of taxpayers' money that's being wasted, but I don't think NASA is one of them.
Nanowiring, and especially CONTROLLED nanowiring will be one of the big enabling technologies for the next generation of electronics (and *PLUG* related to what I'm studying). Researchers have already been able to produce nano-scale wiring that's approximately this size scale: conductive carbon nano-tubes and metallic nanowires made via various means (the last one is not comprehensive BTW) but I doubt anything would beat this in terms of cost and speed of production. But the real boon that could be provided by this will be in getting wiring from electrode A to electrode B (say, from a contact pad on a small square of nanocircuitry to more conventional circuitry on a microchip) reliably, cheaply and quickly.
Some time ago you said that Boy Scouts are all about what's right and honorable. I think I speak for all scientists (and aspiring ones like myself) when I say that we are about knowledge and truth and not about what is immediately useful and practical. We pursue information, regardless of what it is, in the hopes that it'll lead to something eventually, or just for the sake of knowing it. I think it's often been said that if we all had lived in the here and now, that we wouldn't have gotten past sticks, stones, and fleeing from the first signs of danger. As researchers, we add our brick, and hope that what we're building forms the foundations for something else (to paraphrase a colleague of mine).
Sure, we may not get Jurassic Park out of this, but is knowing about dinosaurs who they were and why they disappeared any less laudible of a goal? Historians say that those who learn nothing from the past are doomed to repeat it. Knowing about previous forms of life can help us understand (and deal with or preserve?) those that are here today.
The Greeks eschewed science that *was* applicable because they thought that it wasn't a sufficent exercise of the mind. Clearly, this attitude is a little wrong-headed but Science isn't always obvious, nor its applications. Two hundred years ago, electricity was a curiosity and the mathematics governing it a flight of fancy. Relativity didn't have any obvious applications at the time, and now it helps us move around the globe.
To base all research purely on what's immediately obvious and applicable (while it must be done) will lead to no new ideas and stagnation (or so I think). To some extent though, there is something with a tinge of what you're talking about though: the grant committees that award the money required to do research. However (from my admitedly not direct knowedge) they decide whether or your research has promise, and leads to the greater body of knowledge for humanity as a whole, rather than something strictly utilarian and applicable tomorrow.
Knowledge for its own sake can be a laudable goal. Who's to say that something we learn today (whoever esoteric seeming) may not become useful tomorrow?
Do you have a reference for the rotaxane refutation? I'd definitely like to check that one out. The initial paper I cited seemed fairly confident about the matter, and a quick ISI check indicates that it seems to have inspired some follow-up work as well. I only read the initial article, however. When/where does your paper come out?
This is why they're typically fabricated in parallel and largely remain experimental:)
To illustrate just how new this field currently is, researchers at HP's QSR division (check out one of my earlier posts in this story) managed to create an array of several hundred molecular switch cells (each containing hundreds of molecules of rotaxane) that measured around a micron (10^-6 meters) on a side via self-assembly. In order to interface with this however, they sprinkled gold 'dust' between the array and more traditionally fabricated micro-circuitry (though I can't find the link at the moment)
Disclaimer: IAAM/NT (I am a micro/nanotechnologist)
In a word, no (for this particular incarnation, anyway). K. Eric Drexler said that he wished he had never invented the phrase Grey Goo. Just because something is happening at the molecular or atomic regime does not necessarily mean that it's going to propagate out of control and consume the world.
We may have to worry about other things related to micro/nanotechnology (toxicity, byproducts, disposal, etc.), but I doubt we will have to worry about the grey goo for quite some time to come.
A one-molecule transistor would seem nice. I've heard of better: A Single Electron Transistor (SET)
Close, but SETs run the gamut from being single molecules (those based on carbon nanotubes) to something resembling a 'traditional' transistor structure (and of comparable dimensions). The single-electron portion refers to the current passing through these devices.
While much of the work in SETs remains experimental, many researchers have succeeded in creating room-temperature SETs over the last decade (if you try this search on isiknowledge, you get something like 15 pages of references) with varying degrees of success and ease of fabrication.
(Resubmitted since I forgot to log in...)
I have to wonder how reliable is a 1 molecule switch.
Doesn't sound like much room for wear and tear;)
While many molecular electronic devices work (theoretically) with a single molecule, in practice, they are typically being used in a parallel fashion (lots and lots of devices used as a single transistor or diode or what not). Sounds inefficient, but this is the easiest way of connecting to these devices and to produce them (usually some form of self-assembly is required which, as it stands, will result in these parallel structures)
Regarding wear and tare of molectronics, the QSR (Quantum Scientific Research group at HP developed rotaxane molecules, which are a sort of molecular switch and got about 200 or so write cycles out of them. I highly recommend reading the paper itself since it overviews aspects of molecular electronics, surveys other devices, shows how molectronics are typically made, and, most importantly, is hosted by the authors and thus freely available online.
I think Bush already pushed for the comparison some time ago, but this is exactly what happened in WWII as well (though it was Churchill who was the English conservative, and Roosevelt the American liberal). Opposite ends of the spectrum again, but on the other side. Strangely enough, there was a NYTimes story last week about Clinton taping an ad endorsing Tony Blair for the upcoming elections, but the conservative Tories got nothing from Bush (well, I guess that'd be pretty obvious, but just wanted to point it out nonetheless)
Now, is it just me or does Bush get compared to FDR (or at least associated with him) a lot? (The specific comparison when he's deemed a wartime leader, the social security aspect, spending, etc.)
Slashdot Mirror
You can usually go to eBay and find hundreds of high-intensity LED lots (usually of 50 or 100) for sale from various sellers in Hong Kong (find someone with a low combined bid price and shipping). For Joe Hobbyist, it's usually much cheaper than ordering it from most of the component suppliers out there.
Lex Luthor called and wants his scheme back!
Though to be fair, he tried to shorten his capitalization period a little...
I'm not sure about the exact duplicate part, but here's at least one Easter Egg targeted towards Soviet IC reverse engineers.
The DOE agrees with you! (That's a picture of Solar One, a pilot solar power project in the Mojave 20-odd years ago; I think it's actually being used as part of California's power grid now)
Check out Wikipedia's article on solar power for heliostats (the tracking mirrors) and various other arrangements that are used in similar solar thermal plants (or death rays!)
Sorry, I didn't mean to condescend. If you're still reading, only the parabola has a point focus where any incoming ray of light that's parallel to the latus rectum (see, it's a learning experience for me too!) ends up at the focus. Almost everything else is subject to something similar to spherical aberration where the focus is smeared out. Like you say, it doesn't have to be a parabola to work, but it's probably the most efficient (in terms of number of people with mirrors, anyway)
Some already do...
One of the definitions of a parabola (the one I got when I was in high school anyways) is that it's the collection of points equidistant (the same distance) from a point, the focus, and a line, the directrix. One of the side notes of this is that the lines coming from the directrix are all at right angles to the directrix. So basically, if you have nicely collimated (made up of all parallel rays--a good assumption given that we're however many millions of miles away from the sun) and they're all coming in at right angles to the parabola's directrix (this is where the aiming comes into play) all the incoming rays of light will be aimed directly at the focus of the parabola. By widening or narrowing your parabola (making sure that it is still, in fact, a parabola) you can change your focal length (how far out you shoot).
Since a picture is worth a 1000 words, check out the second image at Mathworld's article.
No, Jon Bardeen, Walter Brattain and William Shockley invented the bipolar junction transistor, though Shockley was dropped from the patent because his ideas were too close to the field effect transistor which had earlier been patented (and which he later succeeded in actually building).
Jack Kilby at Texas Instruments succeeded in inventing the integrated circuit. Robert Noyce of Fairchild Semiconductor was also awarded a patent for an integrated circuit six months later (the two are credited as being the co-inventors of the integrated circuit) and ultimately, it was his planar design process that was the basis for most future integrated circuits)
From George Orwell's 1984:
"[...] duckspeak, to quack like a duck. It is one of those interesting words that have two contradictory meanings. Applied to an opponent, it is abuse, applied to someone you agree with, it is praise."
Courtesy of the online searchable version.
It was a remark made in jest, like (I thought) most of the "xxx, is that you?" memes. While I probably should have qualified that initially, I didn't mean to suggest that you were an eco-terrorist, or wished for the wholesale destruction of human kind.
FWIW, I do agree with some of your sentiments; we need to be a warden to what little (in many places) remains of our environment. Headlong destruction of natural habitats and countless species of plants/animals/etc. can only lead to (or has already led to) trouble.
Ra's al Ghul is that you?
(For those who didn't have a misspent childhood reading comic books, Ra's al Ghul is the eco-terrorist supervillain in Batman who seeks "balance" between man and nature, usually involving the extermination of the former)
Scotty: "Computer, Computer"
That last one was one of my favorite scenes from The Voyage Home. For those less in the know:
Setting: 20th century earth, inside a research lab with Scotty seated at a Mac and with Spock(?) and scientist behind him.
Scotty: (picks up the mouse) "Computer."
Nothing happens
Scotty: Computer."
Scotty: (looks down at the keyboard) "Ah, a tactile interface. How quaint."
...and I'm only in my early 20s! (thanks to late night re-runs on CBC)
/oblig
Star Trek has been a major influence in my life, and will always be a fond part of my childhood memories. RIP, Jimmy
Beam him up!
The Amish (and I believe to a lesser extent, Mennonites in general) believe that you have to make a conscious and informed decision to be baptised and formally join their faith, so Rumspringa lets them have a taste of life on the outside. The majority usually decide to stay, but UPN had a reality TV show Amish in the City and for some reason, the four Amish that were featured all decided to leave the community. Probably had something to do with the fact that they put them up with a bunch of "English" in a big mansion, and got them doing various activities together.
Not to ruin a perfectly good joke, but for whatever reason, the Amish seem pretty gung-ho for biotechnology and what not (at least in their embrace of GM crops and what not). Another reason may be the fact that the Amish also all descended from a few hundred Swiss Germans (who did and continue to marry within themselves) so they suffer from the founder effect.
According to the wikipedia article on the Amish, there was a 60 Minutes piece some time ago about a clinic the Amish themselves set up in Ohio in order to investigate Amish-only genetic diseases (including one that caused severe mental retardation and various other maladies).
I dunno if you're serious or not, so I'll bite.
You may think this to be evidence of the waste that is NASA, but there are many more who would say that this is a shining example of the return reaped from the investment in NASA and in science as a whole. DISCLAIMER: I won't claim to be one since I'm not an american and don't directly contribute to funding either of these.
This is probably what our own solar system looked like some 5 billion years ago, and probably how our own planet came to be. And now we can actually see it. That's powerful (to me anyways). I choose to believe that the fact that this is happening in our own backyard (galactically speaking), and around a star very much like our own may mean that we're not alone in this universe.
Sure, there's a lot of taxpayers' money that's being wasted, but I don't think NASA is one of them.
IAAANTE (I Am An Aspiring Nano-Tech Engineer)
Nanowiring, and especially CONTROLLED nanowiring will be one of the big enabling technologies for the next generation of electronics (and *PLUG* related to what I'm studying). Researchers have already been able to produce nano-scale wiring that's approximately this size scale: conductive carbon nano-tubes and metallic nanowires made via various means (the last one is not comprehensive BTW) but I doubt anything would beat this in terms of cost and speed of production. But the real boon that could be provided by this will be in getting wiring from electrode A to electrode B (say, from a contact pad on a small square of nanocircuitry to more conventional circuitry on a microchip) reliably, cheaply and quickly.
Okay, I'll bite...
Some time ago you said that Boy Scouts are all about what's right and honorable. I think I speak for all scientists (and aspiring ones like myself) when I say that we are about knowledge and truth and not about what is immediately useful and practical. We pursue information, regardless of what it is, in the hopes that it'll lead to something eventually, or just for the sake of knowing it. I think it's often been said that if we all had lived in the here and now, that we wouldn't have gotten past sticks, stones, and fleeing from the first signs of danger. As researchers, we add our brick, and hope that what we're building forms the foundations for something else (to paraphrase a colleague of mine).
Sure, we may not get Jurassic Park out of this, but is knowing about dinosaurs who they were and why they disappeared any less laudible of a goal? Historians say that those who learn nothing from the past are doomed to repeat it. Knowing about previous forms of life can help us understand (and deal with or preserve?) those that are here today.
The Greeks eschewed science that *was* applicable because they thought that it wasn't a sufficent exercise of the mind. Clearly, this attitude is a little wrong-headed but Science isn't always obvious, nor its applications. Two hundred years ago, electricity was a curiosity and the mathematics governing it a flight of fancy. Relativity didn't have any obvious applications at the time, and now it helps us move around the globe.
To base all research purely on what's immediately obvious and applicable (while it must be done) will lead to no new ideas and stagnation (or so I think). To some extent though, there is something with a tinge of what you're talking about though: the grant committees that award the money required to do research. However (from my admitedly not direct knowedge) they decide whether or your research has promise, and leads to the greater body of knowledge for humanity as a whole, rather than something strictly utilarian and applicable tomorrow.
Knowledge for its own sake can be a laudable goal. Who's to say that something we learn today (whoever esoteric seeming) may not become useful tomorrow?
Hmmm... That's what ghutchis said as well...
Do you have a reference for the rotaxane refutation? I'd definitely like to check that one out. The initial paper I cited seemed fairly confident about the matter, and a quick ISI check indicates that it seems to have inspired some follow-up work as well. I only read the initial article, however. When/where does your paper come out?
This is why they're typically fabricated in parallel and largely remain experimental :)
To illustrate just how new this field currently is, researchers at HP's QSR division (check out one of my earlier posts in this story) managed to create an array of several hundred molecular switch cells (each containing hundreds of molecules of rotaxane) that measured around a micron (10^-6 meters) on a side via self-assembly. In order to interface with this however, they sprinkled gold 'dust' between the array and more traditionally fabricated micro-circuitry (though I can't find the link at the moment)
Disclaimer: IAAM/NT (I am a micro/nanotechnologist)
In a word, no (for this particular incarnation, anyway). K. Eric Drexler said that he wished he had never invented the phrase Grey Goo. Just because something is happening at the molecular or atomic regime does not necessarily mean that it's going to propagate out of control and consume the world.
We may have to worry about other things related to micro/nanotechnology (toxicity, byproducts, disposal, etc.), but I doubt we will have to worry about the grey goo for quite some time to come.
Ummm, not to spoil your fun or anything, but nanotubes are single molecules!
A one-molecule transistor would seem nice. I've heard of better: A Single Electron Transistor (SET)
Close, but SETs run the gamut from being single molecules (those based on carbon nanotubes) to something resembling a 'traditional' transistor structure (and of comparable dimensions). The single-electron portion refers to the current passing through these devices.
While much of the work in SETs remains experimental, many researchers have succeeded in creating room-temperature SETs over the last decade (if you try this search on isiknowledge, you get something like 15 pages of references) with varying degrees of success and ease of fabrication.
For more on SETs and their operation, google for quantum blockade and/or SETs. The first hit when you google for both those terms links to a review paper that seems pretty decent.
(Resubmitted since I forgot to log in...) I have to wonder how reliable is a 1 molecule switch. Doesn't sound like much room for wear and tear ;)
While many molecular electronic devices work (theoretically) with a single molecule, in practice, they are typically being used in a parallel fashion (lots and lots of devices used as a single transistor or diode or what not). Sounds inefficient, but this is the easiest way of connecting to these devices and to produce them (usually some form of self-assembly is required which, as it stands, will result in these parallel structures)
Regarding wear and tare of molectronics, the QSR (Quantum Scientific Research group at HP developed rotaxane molecules, which are a sort of molecular switch and got about 200 or so write cycles out of them. I highly recommend reading the paper itself since it overviews aspects of molecular electronics, surveys other devices, shows how molectronics are typically made, and, most importantly, is hosted by the authors and thus freely available online.
I think Bush already pushed for the comparison some time ago, but this is exactly what happened in WWII as well (though it was Churchill who was the English conservative, and Roosevelt the American liberal). Opposite ends of the spectrum again, but on the other side. Strangely enough, there was a NYTimes story last week about Clinton taping an ad endorsing Tony Blair for the upcoming elections, but the conservative Tories got nothing from Bush (well, I guess that'd be pretty obvious, but just wanted to point it out nonetheless)
Now, is it just me or does Bush get compared to FDR (or at least associated with him) a lot? (The specific comparison when he's deemed a wartime leader, the social security aspect, spending, etc.)