I've been working on a NASA solar sails project, and our solar sails (still in the design and simulation phase, to be sure) have nothing to do with reflecting light, as this paper suggests.
The sun gives off not only light, but also spits off extremely fast moving plasma, called the solar wind. The wind, though not very dense, typically moves as a speed of several hundred miles per second. That's around a million miles an hour. (You can check current contitions here). The idea is to use the momentum from the solar wind, which is mostly ionized hydrogen, not the light from the sun, to propel the spacecraft. (There are some very good images on the website.)
The most interesting approach was suggested by Robert Winglee of the University of Washington. He suggest using a giant magnetosphere (essentially a magnetic field stretched out by a plasma) as a sail. The magnetophere deflects the solar wind, transferring momentum into the spacecraft. There is also another advantage - the magnetosphere works as a shield to keep the wind from damaging the spacecraft itself.
The "sail" is made from an ionized gas trapped in a magnetic field. It's easy to let the sail out and take it in, and if the sail ever "breaks," you can just make a new one using more plasma.
So, despite what the paper has to say, solar sail research is alive and well. It's just that the most promising designs work a little differently than the author thought.
I'm surprised at what appears to be a complete lack of small/quiet desktop systems using the new Pentium M, or even the entire Centrino chipset.
It seems like the Pentium M, even on a laptop motherboard, would be the ideal way to make an extremely small, fanless (at least for the 7W version of the chip) pc.
Has anyone seen something like this? Would it be difficult to make one?
Apple Power Mac 2.0 GHz G5 (single processor) 840.
A few things really stand out here:
Even a 2.0 GHz G5 machine, which isn't even shipping - is only 21% faster than a commodity P4, according to Apple. (Apple only give the numbers using one of the processors. This is on the floating point test, too, which favors the G5. This is absolutely amazing to me. Despite a 1 GHz bus and a 64 bit architecture, and accepting Apple's questionable benchmark, their cpu is only 21% faster? WTF?
But using the specs from the Spec2000 website make the G5 look even more disappointing. Apparently a fast P4 (which is available today) is significantly faster than the fastest G5. According to Dell, it's 30% faster. According to Intel, it's 44% faster. That's a huge difference. And to those of you who say it's not, consider if someone sold you a 2 GHz chip, and when you looked inside the box, you saw it was actually running at 1.12 GHz. You'd be pissed, and rightfully so.
(An Itanium II, btw, is 61% faster, running at half the clock speed. Incredible.)
Why does Intel say its sytems are 75% faster than Apple says they are? I really don't know. But I seriously doubt that it's pure coincidence that Apple is the only company that can't get these machines to run fast.
I'm sure this will be resolved in a few months, once the results can be independently (in the "not under contract by Apple" sense of the word) verified. But I, for one, was expecting quite a bit more out of this chip, and have a very hard time understanding how Apple did not cook the books on this one...
The other thing that kills me is that the article mentions sites that require Internet Explorer compatability... Since when did Mac IE have the same rendering engine as windows IE? From what I recall if the page doesn't work in mozilla, it prolly won't work in Mac IE either. Oh well, I say no loss here, I'll take safari over IE any day.
The problem isn't with standards compliance. The problem is that when certain web servers see that you are using a browser other than I.E., they actually refuse to serve the page, with a message such as "This site is best viewed with Internet Explorer, click here to download..." even though the page would look fine (better?) in Mozilla (or Safari).
I suspect that this is a default (or common) setting with Microsoft's web server, or just the result of naive webmasters. (Does anyone know more about this?) But the situation will undoubtedly improve as Microsoft refuses to support Explorer. Remember, dropping I.E. for the Mac is a trend - they recently annouced that they're no longer offering stand-alone upgrades for Windows machines, either, although they'll let you upgrade when you upgrade your operating system - really just a clever way to start charging for the product. And this could only help to push people towards the better (Explorer still doesn't block pop-ups?), free alternatives
I came upon this article, "PPC 970: is it enough?", when looking into the 970 a while ago, which looks at the performance of the chip using SPECfp and SPECint tests. There are a few similar articles on the web as well. It goes through a bit of performance testing, but here's the spoiler:
... if the PowerPC 74xx/75xx running at 1GHz roughly equals the performance of a 1.6 GHz Pentium 4, a PowerPC 970 at 1GHz equals a 2 GHz Pentium 4.
This means, a 1.8 GHz 970 would compare to a 3.6 GHz PIV, putting the two chips on very close to the the same standing when the 970 is released.
Of course, it appears that the tests do not look at the Altivec optimized code, which could make a huge difference, especially considering just how much Altivec (or "velocity engine") code has been integrated into Apple software.
The chip could still be quite impressive, especially compared with the g4... I was a little disappointed, though, being under the impression that it would blow everything else out of the water, when in reality, all the 970 does is compete favorably.
I going to catch hell for saying this, but ...
on
Microsoft's Athens PC
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· Score: 1
I would love to see telephony return to the PC. My Windows 95 Pentium 133 had a built in full duplex speaker phone (one where you could talk and listen and the same time). At the time, I thought that a built in high-quality hands-free telephone was a pretty impressive feature (and probably added all of $5 to the price of the machine), and I still have no idea why they went away. Apple actively killed the idea, Microsoft just let it die, and the Linux platform has a hard time directing the evolution of hardware.
Apple has said it was trying to create "something so completely different from what Microsoft was doing that what happened in Redmond wouldn't matter"... and true, Microsoft let slip the niche market for really slow computers that look like large white boobs, and shies away from wildly misrepresenting its products (Steve Jobs tends to mis-pronounce the number "three," as in "hours of battery life in a new Power Book," or "USB ports on an iBoob," as something which sounds remarkably like "five." Huh?)
Don't get me wrong. Linux rocks, and I would love to see it succeed, but I had to put it down for a while because my laptop often wouldn't wake from sleep, and the ability to switch users in XP is cool. (And before you bash that one, remember that Apple is putting user switching in 10.3). The fact is, Microsoft bashing is easy - just copy a Slashdot comment from one MS discussion and paste it into the next. Making a better PC (or Mac, or Linux box) is much, much harder.
Last time I checked (Solaris 8), Sun would give you the operating system for free... but then charge almost $2000 for the Forte compiler.
It doesn't look like this has changed it all, at least by looking at the website. Of course, Sun may be totally justified by doing this - they have to recover their costs somehow, and besides, it may not matter for a server machine - but at the same time, comparing saying Solaris is free in the same way as Linux is a bit deceiving.
I would be curious what other think about this... for instance, is the gcc available for Solaris? Does Forte (Sun's compiler collection) have any advantages?
These new keyboards could be incredible - as someone pointed our, just try typing on your desk, it feels pretty good. And I imagine that the jarring aspect of a keyboard comes from a mechanical switch (or membrane) clicking and sending shockwaves through your fingers, not the tapping itself. I think several million years of evolution created fingers that tap just fine with no major damage, though.
But what I want to know is, if you're going to re-invent the keyboard, why not do it right? The most comportable keyboard I ever used was the Smartboard(or here)
. Instead of just turning the keyboard in, like those crappy Microsoft keyboards, they also line the keys up correctly. About time - the only reason key rows are offset like they are is historical accident. Key rows used to be offset so all the mechanical arms would have room to reach the keys - not because they're even close to comportable.
And don't even get me started on Dvorak, which I've used for the past six years. Novel idea - why not use a key layout which is optimized for speed, comport, and accuracy, instead of one which was custom-make to slow you down.
Of course, with a laser keyboard, you could easily program whatever layout you want (with the correct labels), and possibly even use a Smartboard-type layout (although it is patented)...
I have a friend who makes solar powered, Braitenberg inspired artwork from old computer parts. They're far more interesting in person, but you can check out his website
Slashdot Mirror
The sun gives off not only light, but also spits off extremely fast moving plasma, called the solar wind. The wind, though not very dense, typically moves as a speed of several hundred miles per second. That's around a million miles an hour. (You can check current contitions here). The idea is to use the momentum from the solar wind, which is mostly ionized hydrogen, not the light from the sun, to propel the spacecraft. (There are some very good images on the website.)
The most interesting approach was suggested by Robert Winglee of the University of Washington. He suggest using a giant magnetosphere (essentially a magnetic field stretched out by a plasma) as a sail. The magnetophere deflects the solar wind, transferring momentum into the spacecraft. There is also another advantage - the magnetosphere works as a shield to keep the wind from damaging the spacecraft itself.
The "sail" is made from an ionized gas trapped in a magnetic field. It's easy to let the sail out and take it in, and if the sail ever "breaks," you can just make a new one using more plasma.
So, despite what the paper has to say, solar sail research is alive and well. It's just that the most promising designs work a little differently than the author thought.
It seems like the Pentium M, even on a laptop motherboard, would be the ideal way to make an extremely small, fanless (at least for the 7W version of the chip) pc.
Has anyone seen something like this? Would it be difficult to make one?
The numbers, according to Apple, are
A few things really stand out here:
Even a 2.0 GHz G5 machine, which isn't even shipping - is only 21% faster than a commodity P4, according to Apple. (Apple only give the numbers using one of the processors. This is on the floating point test, too, which favors the G5. This is absolutely amazing to me. Despite a 1 GHz bus and a 64 bit architecture, and accepting Apple's questionable benchmark, their cpu is only 21% faster? WTF?
But using the specs from the Spec2000 website make the G5 look even more disappointing. Apparently a fast P4 (which is available today) is significantly faster than the fastest G5. According to Dell, it's 30% faster. According to Intel, it's 44% faster. That's a huge difference. And to those of you who say it's not, consider if someone sold you a 2 GHz chip, and when you looked inside the box, you saw it was actually running at 1.12 GHz. You'd be pissed, and rightfully so.
(An Itanium II, btw, is 61% faster, running at half the clock speed. Incredible.)
Why does Intel say its sytems are 75% faster than Apple says they are? I really don't know. But I seriously doubt that it's pure coincidence that Apple is the only company that can't get these machines to run fast.
I'm sure this will be resolved in a few months, once the results can be independently (in the "not under contract by Apple" sense of the word) verified. But I, for one, was expecting quite a bit more out of this chip, and have a very hard time understanding how Apple did not cook the books on this one ...
The problem isn't with standards compliance. The problem is that when certain web servers see that you are using a browser other than I.E., they actually refuse to serve the page, with a message such as "This site is best viewed with Internet Explorer, click here to download
I suspect that this is a default (or common) setting with Microsoft's web server, or just the result of naive webmasters. (Does anyone know more about this?) But the situation will undoubtedly improve as Microsoft refuses to support Explorer. Remember, dropping I.E. for the Mac is a trend - they recently annouced that they're no longer offering stand-alone upgrades for Windows machines, either, although they'll let you upgrade when you upgrade your operating system - really just a clever way to start charging for the product. And this could only help to push people towards the better (Explorer still doesn't block pop-ups?), free alternatives
Of course, it appears that the tests do not look at the Altivec optimized code, which could make a huge difference, especially considering just how much Altivec (or "velocity engine") code has been integrated into Apple software.
The chip could still be quite impressive, especially compared with the g4 ... I was a little disappointed, though, being under the impression that it would blow everything else out of the water, when in reality, all the 970 does is compete favorably.
Apple has said it was trying to create "something so completely different from what Microsoft was doing that what happened in Redmond wouldn't matter" ... and true, Microsoft let slip the niche market for really slow computers that look like large white boobs, and shies away from wildly misrepresenting its products (Steve Jobs tends to mis-pronounce the number "three," as in "hours of battery life in a new Power Book," or "USB ports on an iBoob," as something which sounds remarkably like "five." Huh?)
Don't get me wrong. Linux rocks, and I would love to see it succeed, but I had to put it down for a while because my laptop often wouldn't wake from sleep, and the ability to switch users in XP is cool. (And before you bash that one, remember that Apple is putting user switching in 10.3). The fact is, Microsoft bashing is easy - just copy a Slashdot comment from one MS discussion and paste it into the next. Making a better PC (or Mac, or Linux box) is much, much harder.
It doesn't look like this has changed it all, at least by looking at the website. Of course, Sun may be totally justified by doing this - they have to recover their costs somehow, and besides, it may not matter for a server machine - but at the same time, comparing saying Solaris is free in the same way as Linux is a bit deceiving.
I would be curious what other think about this ... for instance, is the gcc available for Solaris? Does Forte (Sun's compiler collection) have any advantages?
But what I want to know is, if you're going to re-invent the keyboard, why not do it right? The most comportable keyboard I ever used was the Smartboard (or here) . Instead of just turning the keyboard in, like those crappy Microsoft keyboards, they also line the keys up correctly. About time - the only reason key rows are offset like they are is historical accident. Key rows used to be offset so all the mechanical arms would have room to reach the keys - not because they're even close to comportable.
And don't even get me started on Dvorak, which I've used for the past six years. Novel idea - why not use a key layout which is optimized for speed, comport, and accuracy, instead of one which was custom-make to slow you down.
Of course, with a laser keyboard, you could easily program whatever layout you want (with the correct labels), and possibly even use a Smartboard-type layout (although it is patented) ...
I have a friend who makes solar powered, Braitenberg inspired artwork from old computer parts. They're far more interesting in person, but you can check out his website