I've never understood how phase locking, resonance, whatever you call it works.
In a nutshell, gravity causes tides, which create friction, which slows relative rotation until the tidal lock is achieved. The ocean tides on Earth caused by the moon have a net frictional effect of slowing down Earth's rotation relative to the moon. This applies to any non-rigid parts, such as a molten core. The Moon was probably tidally locked while it retained a molten core, but was then eventually "frozen" into a permanent static tidal bulge.
The moon currently resists rotation because the tidal forces still "stretch" it toward and away from Earth, and rotating it would be akin to a dancer pulling in her arms; i.e. it takes energy, which is gradually dissipated by friction because the moon is not absolutely rigid. (Think mini-moonquakes.) True, if the moon were perfectly spherical it would not be tidally locked, but even a small asymmetry will amplify itself over time and create a lock.
...but if there's a new crater on a side of the moon we can see, maybe it'd be deep enough to get some real insight about the inside of the moon.
Or if an asteroid strikes the moon a glancing blow, setting it spinning so we can see the far side ourselves...!!
How much energy would that take, and would a dinosaur-killer-size asteroid impact be enough? The moon has a static "solid tide" of roughly 50 meters, bulging toward and away from the Earth, which maintains the tidal lock. How much of a push would it take to cause a 90-degree libration?
To get the initial spools and associated hardware up to GEO, Brad Edwards calculates (if an MPD engine is used for the LEO to GEO transfer) that the launch cost could come downn to about $1 billion for 4 Atlas 5 launches
So the ribbon goes up in 4 pieces, which are then tied together with, what, granny knots?
Yeah, and will it mean that parts of the world at sea-level will temporarily be affected?
I doubt it; I'd guess that the atmosphere itself would prevent the Van Allen Belts' radiation from penetrating too far. Then again, at the South Pole, with no ozone layer, who knows what could get through?
When physicists say "teleportation", they are describing the transfer of key properties from one particle to another without a physical link. Researchers from the University of Vienna and the Austrian Academy of Science used an 800m-long optical fibre fed through a public sewer system tunnel to connect labs on opposite sides of the River Danube.
Wow. I knew the wireless sewer would catch on eventually.
Who says that what is recorded in the Bible as Ararat is the same mountain we know of today as Ararat?
Indeed. Noah's Ark didn't land on Ararat, but on another mountain of the same name.
Re:It's the same as in computers in general...
on
Beyond Megapixels
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· Score: 1
Look at screens. Graphics cards have improved massively (electronics), screens (optics) used to be 1024x768 quite a while back, and typically aren't more than 1600x1200 now. The LCDs will hopefully change that though, since they're much more scalable (make more pixels) than a CRT (move beam faster).
See, this is why I want one of these. Unfortunately, there are no Mac-compatible video cards (yet) that can drive this puppy, and the PC cards that can still cost thousands of dollars. Still I must say, 3840x2400 at 22" (204dpi) is nothing to sneeze at. (or on.)
Then again, my Dell laptop packs 1920x1200 resolution into a 15" display, which is razor-sharp in its own right (150dpi). Jarring to realize that's barely over 2 megapixels.
Of course, as soon as they have a WHUXGA screen (7680x4800) on a 12" laptop, I'm there.
Too fine a lens will cause aliasing artifacts. This can be understood by the Nyquist Theorem.
This depends on the shape of the CCD active areas that are used to capture photons. In the "worst case" where the receptors are essentially discrete points on a grid, an optical blur is needed so photons that would otherwise land in between the sensors have a chance to be captured. In practice, I would guess that the sensors cover about 50% of the usable area, so the remaining 50% must be made up with low-pass filtering to avoid aliasing. (Think of filming headlights; if they're in focus they'll be two discrete points of light, but as you defocus the lights will expand until they overlap.)
A similar problem also comes up in motion video; the aperture is typically open 75% of the time, then closed 25% while the film advances. This results in motion aliasing such as helicopter blades and wagon wheels spinning backwards, etc. Digital video may be able to substantially reduce this problem, but ironically most people have grown accustomed to it, to the point where non-aliased video simply doesn't "look right."
The Foveon approach is a step in the right direction for image capture, since the Bayer interpolation from most other cameras is prone to all sorts of artifacts. Perhaps a camera could be built that would expose the same CCD array through red, green and blue filters in sequence, then apply software to compensate for slight motion between frames.
Similarly, imagine a camera that would expose the CCD for 1/10,000 of a second, then 1/1000, then 1/100, then 1/10, and combine the resulting frames into a single high-dynamic-range image. When the sun is millions of times brighter than the shadows, [0..255] simply isn't going to do justice.
In my opionion, the next few years of digital photography is going to be mighty interesting.
...you can just view them from sixty feet away and the video delay will exactly compensate for the speed-of-sound delay. No problem.
Yes, but by the time you move sixty feet away, the light will lag by forty additional nanoseconds, which forces you to have to move further away still... so they can never be in sync. It's the Zenith Paradox.
I remember hearing a while back about a completely different approach to terraforming Mars. The idea was based on the observation that there are some deposits of very dark sand/dust relatively near the poles, so what we should do is strategically place a few nuclear bombs at those dunes, wait til the Martian winds are blowing toward the poles, and set off the nukes.
This would cover the poles with layers of dark material, which would then increase the absorption of solar energy, resulting in the melting/sublimation of the icecaps. The radiation factor would be insignificant in the scheme of things.
Here's another recent article. The Shuttle C concept was based on the idea of replacing the orbiter with a third-stage rocket, forming a highly effective heavy-lift launch vehicle. Great for humans to mars, among other things.
Slashdot Mirror
According to my Chinese friend, the immunity comes from eating stinky fermented tofu and thousand-year egg.
I personally plan to remain vulnerable. Alas.
I've never understood how phase locking, resonance, whatever you call it works.
In a nutshell, gravity causes tides, which create friction, which slows relative rotation until the tidal lock is achieved. The ocean tides on Earth caused by the moon have a net frictional effect of slowing down Earth's rotation relative to the moon. This applies to any non-rigid parts, such as a molten core. The Moon was probably tidally locked while it retained a molten core, but was then eventually "frozen" into a permanent static tidal bulge.
The moon currently resists rotation because the tidal forces still "stretch" it toward and away from Earth, and rotating it would be akin to a dancer pulling in her arms; i.e. it takes energy, which is gradually dissipated by friction because the moon is not absolutely rigid. (Think mini-moonquakes.) True, if the moon were perfectly spherical it would not be tidally locked, but even a small asymmetry will amplify itself over time and create a lock.
Hope this clarifies.
Or if an asteroid strikes the moon a glancing blow, setting it spinning so we can see the far side ourselves...!!
How much energy would that take, and would a dinosaur-killer-size asteroid impact be enough? The moon has a static "solid tide" of roughly 50 meters, bulging toward and away from the Earth, which maintains the tidal lock. How much of a push would it take to cause a 90-degree libration?
They timed how long it took to calculate PI? That implies that it *FINISHED* calculating pi!
Well, considering it was done on a pc, 640k digits out to be enough for anybody.
wow, windows at 6GHz, think of how much spyware it would take to finally slow it down...
Spyware, feh. Just launch MS Word.
...wanking will make you go blind. That is, if you do it while surfing for pr0n on one of these displays.
At least, you'd need one with Steady Shot motion compensation to balance out the jiggling...
So how long until someone pops off the aluminum stand, hooks up a small external battery and just calls the thing a G5 Laptop?
Bonus for being the first to use it on an airplane... (most airplanes have power plugs available anyway, don't they?)
To get the initial spools and associated hardware up to GEO, Brad Edwards calculates (if an MPD engine is used for the LEO to GEO transfer) that the launch cost could come downn to about $1 billion for 4 Atlas 5 launches
So the ribbon goes up in 4 pieces, which are then tied together with, what, granny knots?
C: Either of the above.
Simply spell out the sequence:
ten, nine, sixty, ninety, seventy, sixty-six...
and look at the number of letters used:
3, 4, 5, 6, 7, 8...
The next item must clearly have nine letters, so either "ninety-six" or "one Googol" will work. (or "seventeen", or "fifty-four", etc.)
Yeah, and will it mean that parts of the world at sea-level will temporarily be affected?
I doubt it; I'd guess that the atmosphere itself would prevent the Van Allen Belts' radiation from penetrating too far. Then again, at the South Pole, with no ozone layer, who knows what could get through?
requirement to avoid ... the South Atlantic Anomaly
Fascinating. But on the subject, if Earth's magnetic polarity flips, would that create a North Atlantic Anomaly? Or, how about removing the Van Allen belts altogether?
When physicists say "teleportation", they are describing the transfer of key properties from one particle to another without a physical link. Researchers from the University of Vienna and the Austrian Academy of Science used an 800m-long optical fibre fed through a public sewer system tunnel to connect labs on opposite sides of the River Danube.
Wow. I knew the wireless sewer would catch on eventually.
Drat, too late...
If only I knew how to touch-type.
then users will need to upgrade to a jPod and perhaps a jPaq for compatability
How about calling it the jWalk?
to the term "floating-point."
The next one is probably Lynx. It goes well with their new eMacs.
They should rename their browser "HyperLynx."
(or if not, perhaps "iBrowse"... ?)
Who says that what is recorded in the Bible as Ararat is the same mountain we know of today as Ararat?
Indeed. Noah's Ark didn't land on Ararat, but on another mountain of the same name.
Look at screens. Graphics cards have improved massively (electronics), screens (optics) used to be 1024x768 quite a while back, and typically aren't more than 1600x1200 now. The LCDs will hopefully change that though, since they're much more scalable (make more pixels) than a CRT (move beam faster).
See, this is why I want one of these. Unfortunately, there are no Mac-compatible video cards (yet) that can drive this puppy, and the PC cards that can still cost thousands of dollars. Still I must say, 3840x2400 at 22" (204dpi) is nothing to sneeze at. (or on.)
Then again, my Dell laptop packs 1920x1200 resolution into a 15" display, which is razor-sharp in its own right (150dpi). Jarring to realize that's barely over 2 megapixels.
Of course, as soon as they have a WHUXGA screen (7680x4800) on a 12" laptop, I'm there.
get home and crap 3/4 of the picture out and still be left with a picture that's high quality enough for a print.
Yay, let's hear it for moving pictures! Would that be called a "Sphinc-jet"?
(Or a low-pass filter?)
(...well, definitely not a kodak moment, anyway..)
Too fine a lens will cause aliasing artifacts. This can be understood by the Nyquist Theorem.
This depends on the shape of the CCD active areas that are used to capture photons. In the "worst case" where the receptors are essentially discrete points on a grid, an optical blur is needed so photons that would otherwise land in between the sensors have a chance to be captured. In practice, I would guess that the sensors cover about 50% of the usable area, so the remaining 50% must be made up with low-pass filtering to avoid aliasing. (Think of filming headlights; if they're in focus they'll be two discrete points of light, but as you defocus the lights will expand until they overlap.)
A similar problem also comes up in motion video; the aperture is typically open 75% of the time, then closed 25% while the film advances. This results in motion aliasing such as helicopter blades and wagon wheels spinning backwards, etc. Digital video may be able to substantially reduce this problem, but ironically most people have grown accustomed to it, to the point where non-aliased video simply doesn't "look right."
The Foveon approach is a step in the right direction for image capture, since the Bayer interpolation from most other cameras is prone to all sorts of artifacts. Perhaps a camera could be built that would expose the same CCD array through red, green and blue filters in sequence, then apply software to compensate for slight motion between frames.
Similarly, imagine a camera that would expose the CCD for 1/10,000 of a second, then 1/1000, then 1/100, then 1/10, and combine the resulting frames into a single high-dynamic-range image. When the sun is millions of times brighter than the shadows, [0..255] simply isn't going to do justice.
In my opionion, the next few years of digital photography is going to be mighty interesting.
...you can just view them from sixty feet away and the video delay will exactly compensate for the speed-of-sound delay. No problem.
Yes, but by the time you move sixty feet away, the light will lag by forty additional nanoseconds, which forces you to have to move further away still... so they can never be in sync. It's the Zenith Paradox.
...that has solved the elliptical curve encryption scheme.
Ahem; that should be elliptic.
just being pedantical.
The master replied, "There was go before there were men."
So you're saying it was invented by women?
I remember hearing a while back about a completely different approach to terraforming Mars. The idea was based on the observation that there are some deposits of very dark sand/dust relatively near the poles, so what we should do is strategically place a few nuclear bombs at those dunes, wait til the Martian winds are blowing toward the poles, and set off the nukes.
This would cover the poles with layers of dark material, which would then increase the absorption of solar energy, resulting in the melting/sublimation of the icecaps. The radiation factor would be insignificant in the scheme of things.
Does this sound completely nutty?
Isn't it about time they switched from assembly to C ?
Yes, as long as it's Shuttle C.
Here's another recent article. The Shuttle C concept was based on the idea of replacing the orbiter with a third-stage rocket, forming a highly effective heavy-lift launch vehicle. Great for humans to mars, among other things.