Philosophically, time doesn't exist in the frequency domain. As for clipping, it turns sinusoids into square waves, the Fourier transform of which has evenly-spaced harmonics going out to infinity (and decaying as 1/f) as described here.
Why should digital clipping be worse? I ask seriously.
The mental model I've got right now is that
digital_clip(x) = x if |x| < 1, sign(x) otherwise
(approximating the signal as real-valued and the output range of the amp as being [-1,1]) whereas
analog_clip(x) = smooth_sigmoid(x)
which results from saturation of the transistors used in the amp. Granted, the latter function is presumably smooth, which means fewer high frequency harmonics will be introduced, but the difference doesn't seem that huge...
Or by digital clipping do you mean "mod 2^N" clipping as whatever number representation used wraps around? Because I've never run across a sound driver that does this...
If the sigmoid is indeed a ton better than the piecewise-linear clipping function, then it could easily be implemented in software at the price of a tiny bit of undistorted dynamic range...
...and, I hadn't been keeping up with this, but a quick google turns up "SED" and "FED" technologies which are even closer to CRTs and which will probably be rolled out eventually (just type these terms into Wikipedia if interested). Though with LED TVs already hitting stores I wonder if they'll offer any substantive advantages.
Plasmas are pretty close to CRTs technologically. Instead of energizing phosphors by shooting electrons at them, they make electric arcs jump through gas in tiny glass cells, which releases a bunch of UV which strikes the phosphors and energizes them. This process is easy to miniaturize but pretty inefficient, hence the perceptible heat radiated by one of these things. But that's beside the point; visually the result should be about the same. So maybe "thin CRTs" are plasma TVs -- just minus the "C" and the "R", and with the one big "T" replaced by millions of individual cells.
Yeah, DC's pretty good, and of course there's no city like New York! Not sure I'd agree about Philly, but fair 'nuff.
It's also possible that season has something to do with it. I lived in Chicago for a summer, and it's during those months that I hear the place comes the most alive. It might be dismal in the winter, who knows.
Hmm.... I'm not so sure about that. Obviously it's dangerous to generalize or stereotype, but this is not the impression I've gotten from the Latinos I've known. And perhaps more persuasively, those majority-Caucasian Americans who are now anti-immigration are themselves probably second- to fourth- generation children of immigrants themselves. So it seems that once you get here and secure the good life for yourself, you just look out for what you perceive to be your own interests regardless of where your family came from.
I was saying that a worldview in which your purpose in life is to get ahead in some giant global capitalist ratrace is pretty dismal and dehumanizing. You think I'm here preaching religion? Hardly.
I don't know how to explain this. This isn't about religion. It's about one example of an answer to the question, "What is my purpose in life," and it just happens to come from a religion (I don't care who makes a statement. I care about the statement itself). And sure, it uses the word 'God,' but that shouldn't cause such hangups, should it? It's just an ill-defined abstraction with some vague connotations. The point is that the statement frames ones purpose as being (1) external: the focus is on an abstraction which is somehow "outside the self;" and (2) accessible: in principle, anyone can do it.
Contrast this to a worldview in which your purpose is "to compete at the global level." This promotes a purpose which is (1) internal: the focus is on making the self more competitive; and (2) elitist: some people just can't compete, and those people are simply worth less in this value system.
Obviously the religious worldview is easy to corrupt (maybe it was promoted from the beginning by charlatans), so I'm not promoting it. Rather I'm comparing it to a different worldview we seem to be in danger of adopting, and arguing that just because the latter is secular and "feels" rational does not mean that it is good.
I'm also saying that, although the 'God' abstraction may not "feel" right any more in a "scientific" worldview, and although religion has throughout history fucked up so very much for so many people, there still may be elements of it that are worth salvaging to temper the dehumanising force of money. (I hardly need to list examples of horrors already unleashed on the world by the latter.) In particular, it is the emphasis on things outside the self, and the inherent egalitarian nature of the ideas, which we might want to find ways of incorporating into our newer and more modern ideologies.
Because if your purpose in life is to out-compete everyone else, then you are worthless: Somewhere out there, there's always somebody who's better at whatever it is that you do than you are. And if we spend all our time competing, then we won't have any for actually living. I just hate the idea of intentionally creating an ideology which glorifies single-minded dog-eat-dog brutality.
It's called an opto-isolator, and from the outside it has only electrical -- not optical -- inputs and outputs. Also most generally it's a generic circuit component, not special network gear.
Well... It's 8k, and the CPUS, according to a quick google, are ~2k apiece new (?! For one CPU?). So presumably you can get the full 80-core experience for 168k.
For comparison, a fast commodity rig might cost, I dunno, 1.5k? Times 80, and you're at 120k? So this thing, fully decked out, is possibly 40% more expensive than an equivalent commodity setup? If it's commensurately faster -- which is easy to believe as the processors are on the same mobo instead of strung across a network -- then it could be a net win to use this machine, maybe?
Anyway, it's hard to say. I'm using ballpark numbers and the results are the same order of magnitude, so it might go either way. The point is that the price doesn't seem completely absurd, at first glance at least...
I've also always left that field blank, but to this day I haven't gotten a single "gay ad" (dunno what that would be). For a while I was being advertised razors (why I don't know). Then something called a "fat cookie" after a Wall conversation about sandwiches -- coincidence? Anyway, the point is simply that I did the same thing but didn't observe the same result.
AFAIK (which is admittedly not a ton) you can string together sequences of orbits based on 3-body problems (around Lagrange points) to form a good initial guess and then optimize this in the full n-body setting.
I'd skimmed that updates page but hadn't found much. I took another look and found a bit more: On this page, for instance, they mention using a simple PD controller for their throttle. That's not too surprising; it's all you need. What I'm more interested in though, and still haven't found, is how they control orientation -- if they're controlling Euler angles individually or doing something fancier on the Lie group of rotations...
Is there any information out there on the stabilizing controllers used by Armadillo to achieve this? Does anyone know what methodology they used? Old-fashioned PID (or really lag-lead) with hand tuning? LQR on a linearized model? Feedback linearization? There are some references to "gains" in passing on the Armadillo website which makes me assume that there's a linear controller somewhere in there under the hood.... Anybody know?
I'm pretty sure you are incorrect. I'm also afraid that this is symptomatic of the kind of "big words and non-understanding" that gets passed off as "knowledge" too often these days...
As for me, optics is quite far from my field, and my knowledge of it is meager, but there was a short time when I read a bit about lasers and Fourier optics when I did some work on FELs (free electron lasers) as an undergrad. (How could I "work on FELs" with "meager knowledge of optics?" I was building a control system for an adjustable resonator, and this didn't really require much knowledge in optics. Nevertheless, I tried to learn a little about lasers in the bargain.)
The point is that in these books, I remember (1) that laser beams were modeled as Gaussian beams, and (2) some fundamental limitations were described on how well you could collimate such a beam, even from a laser. The relevant punchline for this discussion is that there's always a little divergence to a laser beam; it's just small. I remember that the arguments for this were based on Fourier optics but honestly I remember very little about them.
I'm also a tiny bit disturbed by the "knowledge" being thought of in your post as "scientific:" I'm not trying to nitpick or single you out -- and like I said, I'm not claiming some kind of particular expertise here either -- but it feels like many people here are using words like "coherent" because that one word is the "explanation" they received for why lasers "go straight," while by itself a word you don't understand is no explanation at all.
Here's what I mean by "bad explanations" and "no understanding." (The answers are supposed to be bad):
Q: Why does a laser beam not spread out?
A: Because the light is coherent.
Q: What does "coherent" mean?
A: Coherent means that the phase is constant.
Q: Constant in what? Time? Space? Which of these is relevant to going straight? And since you just said "phase," this means we're talking about a Fourier Transform; doesn't this completely eliminate any concept of time and space to begin with?
Can you answer this?
If not, perhaps you too need to learn some more physics.
Presumably one could use a corner reflector. There's no aiming involved, and since they're completely passive they're obviously robust.
...except to things like melting, which I'm afraid any reflector system will have a problem with!!
Well, one possible exception. It occurs to me that you might be able to build a "reflector" based on Compton scattering (or do I mean Thompson scattering? It's been a while...) off of free electrons, which would be immune to melting -- but this would really only work in space... Also, this is probably getting off the original topic because it wouldn't reflect the incident beam back to the source. Maybe it'd be possible to set up a system of electron beams that'd somehow act like a "corner reflector" but it seems like considering such a thing would take some more familiarity with the physics than I have... and considerable mathematical fortitude!;-)
Umm... that's not what he was saying. The US was included in "The West." It was included in the set of "pussies." He was saying that neither Americans nor Europeans can stomach a large war.
I'm not trying to defend the above poster per-se, just to clarify.
I'd always seen a difference between these words actually.
Saboteurs destroy infrastructure ("throw a shoe (French: sabot) in the works."). Terrorists kill people with the aim of, well, instilling terror.
This said, although I disagree with your point about the meanings of these words, I do agree with the larger overall sentiment that the distinction between terrorism and warfare is in the eye of the beholder. Even if we were to agree on a definition like "any intentional attack on a civilian target is terrorism," then we'd have to draw some uncomfortable conclusions. For instance, if we accept this definition, then not just the Axis powers of WWII but also the Allies engaged in terrorism on a massive scale (just consider the firebombing of Tokyo or Dresden, or the nuclear attacks on Hiroshima and Nagasaki).
Sorry dude, but I'm afraid you misunderstand some basics in optics. The intensity is inversely proportional to the area of the wavefront you're at. Consider that energy must be conserved.
(I can't tell if you're subtly trolling or not...)
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Philosophically, time doesn't exist in the frequency domain. As for clipping, it turns sinusoids into square waves, the Fourier transform of which has evenly-spaced harmonics going out to infinity (and decaying as 1/f) as described here.
Why should digital clipping be worse? I ask seriously.
The mental model I've got right now is that
digital_clip(x) = x if |x| < 1, sign(x) otherwise
(approximating the signal as real-valued and the output range of the amp as being [-1,1]) whereas
analog_clip(x) = smooth_sigmoid(x)
which results from saturation of the transistors used in the amp. Granted, the latter function is presumably smooth, which means fewer high frequency harmonics will be introduced, but the difference doesn't seem that huge...
Or by digital clipping do you mean "mod 2^N" clipping as whatever number representation used wraps around? Because I've never run across a sound driver that does this...
If the sigmoid is indeed a ton better than the piecewise-linear clipping function, then it could easily be implemented in software at the price of a tiny bit of undistorted dynamic range...
So what's the deal with "digital clipping?"
...and, I hadn't been keeping up with this, but a quick google turns up "SED" and "FED" technologies which are even closer to CRTs and which will probably be rolled out eventually (just type these terms into Wikipedia if interested). Though with LED TVs already hitting stores I wonder if they'll offer any substantive advantages.
Plasmas are pretty close to CRTs technologically. Instead of energizing phosphors by shooting electrons at them, they make electric arcs jump through gas in tiny glass cells, which releases a bunch of UV which strikes the phosphors and energizes them. This process is easy to miniaturize but pretty inefficient, hence the perceptible heat radiated by one of these things. But that's beside the point; visually the result should be about the same. So maybe "thin CRTs" are plasma TVs -- just minus the "C" and the "R", and with the one big "T" replaced by millions of individual cells.
Yeah, DC's pretty good, and of course there's no city like New York! Not sure I'd agree about Philly, but fair 'nuff.
It's also possible that season has something to do with it. I lived in Chicago for a summer, and it's during those months that I hear the place comes the most alive. It might be dismal in the winter, who knows.
Have you been there? It's a pretty cool city actually.
surely they are pro-immigration.
Hmm.... I'm not so sure about that. Obviously it's dangerous to generalize or stereotype, but this is not the impression I've gotten from the Latinos I've known. And perhaps more persuasively, those majority-Caucasian Americans who are now anti-immigration are themselves probably second- to fourth- generation children of immigrants themselves. So it seems that once you get here and secure the good life for yourself, you just look out for what you perceive to be your own interests regardless of where your family came from.
That wasn't the point at all.
I was saying that a worldview in which your purpose in life is to get ahead in some giant global capitalist ratrace is pretty dismal and dehumanizing. You think I'm here preaching religion? Hardly.
I don't know how to explain this. This isn't about religion. It's about one example of an answer to the question, "What is my purpose in life," and it just happens to come from a religion (I don't care who makes a statement. I care about the statement itself). And sure, it uses the word 'God,' but that shouldn't cause such hangups, should it? It's just an ill-defined abstraction with some vague connotations. The point is that the statement frames ones purpose as being (1) external: the focus is on an abstraction which is somehow "outside the self;" and (2) accessible: in principle, anyone can do it.
Contrast this to a worldview in which your purpose is "to compete at the global level." This promotes a purpose which is (1) internal: the focus is on making the self more competitive; and (2) elitist: some people just can't compete, and those people are simply worth less in this value system.
Obviously the religious worldview is easy to corrupt (maybe it was promoted from the beginning by charlatans), so I'm not promoting it. Rather I'm comparing it to a different worldview we seem to be in danger of adopting, and arguing that just because the latter is secular and "feels" rational does not mean that it is good.
I'm also saying that, although the 'God' abstraction may not "feel" right any more in a "scientific" worldview, and although religion has throughout history fucked up so very much for so many people, there still may be elements of it that are worth salvaging to temper the dehumanising force of money. (I hardly need to list examples of horrors already unleashed on the world by the latter.) In particular, it is the emphasis on things outside the self, and the inherent egalitarian nature of the ideas, which we might want to find ways of incorporating into our newer and more modern ideologies.
Because if your purpose in life is to out-compete everyone else, then you are worthless: Somewhere out there, there's always somebody who's better at whatever it is that you do than you are. And if we spend all our time competing, then we won't have any for actually living. I just hate the idea of intentionally creating an ideology which glorifies single-minded dog-eat-dog brutality.
Touché.
It's called an opto-isolator, and from the outside it has only electrical -- not optical -- inputs and outputs. Also most generally it's a generic circuit component, not special network gear.
not work hard enough to compete on a global level
There was a time when the purpose of life was "to know, love, and serve God." So said the Baltimore Catechism #3.
Now it's apparently "to work hard enough to compete on a global level."
For all religion's flaws, I'm not sure I prefer the latter.
Well... It's 8k, and the CPUS, according to a quick google, are ~2k apiece new (?! For one CPU?). So presumably you can get the full 80-core experience for 168k.
For comparison, a fast commodity rig might cost, I dunno, 1.5k? Times 80, and you're at 120k? So this thing, fully decked out, is possibly 40% more expensive than an equivalent commodity setup? If it's commensurately faster -- which is easy to believe as the processors are on the same mobo instead of strung across a network -- then it could be a net win to use this machine, maybe?
Anyway, it's hard to say. I'm using ballpark numbers and the results are the same order of magnitude, so it might go either way. The point is that the price doesn't seem completely absurd, at first glance at least...
I've also always left that field blank, but to this day I haven't gotten a single "gay ad" (dunno what that would be). For a while I was being advertised razors (why I don't know). Then something called a "fat cookie" after a Wall conversation about sandwiches -- coincidence? Anyway, the point is simply that I did the same thing but didn't observe the same result.
AFAIK (which is admittedly not a ton) you can string together sequences of orbits based on 3-body problems (around Lagrange points) to form a good initial guess and then optimize this in the full n-body setting.
That doesn't kill germs. It just helps remove them from your skin.
AFAIK, plain old soap disrupts cellular membranes and basically causes many bacteria to fall apart, since it messes with surface tension.
So, people who don't believe in God are supposed to confront those who reject science on the basis of faith by being...nice to them?
How often has yelling at somebody convinced them of anything?
Part of the problem is that the whole theist/atheist "debate" is irrelevant. Science does not say that there is no God. It doesn't give a damn.
I'd skimmed that updates page but hadn't found much. I took another look and found a bit more: On this page, for instance, they mention using a simple PD controller for their throttle. That's not too surprising; it's all you need. What I'm more interested in though, and still haven't found, is how they control orientation -- if they're controlling Euler angles individually or doing something fancier on the Lie group of rotations...
Is there any information out there on the stabilizing controllers used by Armadillo to achieve this? Does anyone know what methodology they used? Old-fashioned PID (or really lag-lead) with hand tuning? LQR on a linearized model? Feedback linearization? There are some references to "gains" in passing on the Armadillo website which makes me assume that there's a linear controller somewhere in there under the hood.... Anybody know?
I've heard the screams of the vegetables.
I'm pretty sure you are incorrect. I'm also afraid that this is symptomatic of the kind of "big words and non-understanding" that gets passed off as "knowledge" too often these days...
As for me, optics is quite far from my field, and my knowledge of it is meager, but there was a short time when I read a bit about lasers and Fourier optics when I did some work on FELs (free electron lasers) as an undergrad. (How could I "work on FELs" with "meager knowledge of optics?" I was building a control system for an adjustable resonator, and this didn't really require much knowledge in optics. Nevertheless, I tried to learn a little about lasers in the bargain.)
The point is that in these books, I remember (1) that laser beams were modeled as Gaussian beams, and (2) some fundamental limitations were described on how well you could collimate such a beam, even from a laser. The relevant punchline for this discussion is that there's always a little divergence to a laser beam; it's just small. I remember that the arguments for this were based on Fourier optics but honestly I remember very little about them.
I'm also a tiny bit disturbed by the "knowledge" being thought of in your post as "scientific:" I'm not trying to nitpick or single you out -- and like I said, I'm not claiming some kind of particular expertise here either -- but it feels like many people here are using words like "coherent" because that one word is the "explanation" they received for why lasers "go straight," while by itself a word you don't understand is no explanation at all.
Here's what I mean by "bad explanations" and "no understanding." (The answers are supposed to be bad):
Q: Why does a laser beam not spread out?
A: Because the light is coherent.
Q: What does "coherent" mean?
A: Coherent means that the phase is constant.
Q: Constant in what? Time? Space? Which of these is relevant to going straight? And since you just said "phase," this means we're talking about a Fourier Transform; doesn't this completely eliminate any concept of time and space to begin with?
Can you answer this?
If not, perhaps you too need to learn some more physics.
Presumably one could use a corner reflector. There's no aiming involved, and since they're completely passive they're obviously robust.
...except to things like melting, which I'm afraid any reflector system will have a problem with!!
Well, one possible exception. It occurs to me that you might be able to build a "reflector" based on Compton scattering (or do I mean Thompson scattering? It's been a while...) off of free electrons, which would be immune to melting -- but this would really only work in space... Also, this is probably getting off the original topic because it wouldn't reflect the incident beam back to the source. Maybe it'd be possible to set up a system of electron beams that'd somehow act like a "corner reflector" but it seems like considering such a thing would take some more familiarity with the physics than I have... and considerable mathematical fortitude! ;-)
Umm... that's not what he was saying. The US was included in "The West." It was included in the set of "pussies." He was saying that neither Americans nor Europeans can stomach a large war.
I'm not trying to defend the above poster per-se, just to clarify.
I'd always seen a difference between these words actually.
Saboteurs destroy infrastructure ("throw a shoe (French: sabot) in the works."). Terrorists kill people with the aim of, well, instilling terror.
This said, although I disagree with your point about the meanings of these words, I do agree with the larger overall sentiment that the distinction between terrorism and warfare is in the eye of the beholder. Even if we were to agree on a definition like "any intentional attack on a civilian target is terrorism," then we'd have to draw some uncomfortable conclusions. For instance, if we accept this definition, then not just the Axis powers of WWII but also the Allies engaged in terrorism on a massive scale (just consider the firebombing of Tokyo or Dresden, or the nuclear attacks on Hiroshima and Nagasaki).
Sorry dude, but I'm afraid you misunderstand some basics in optics. The intensity is inversely proportional to the area of the wavefront you're at. Consider that energy must be conserved.
(I can't tell if you're subtly trolling or not...)
For those keeping score, he actually did copy it from Wikipedia.