How public are/were the Jason members? I met somebody from the Dept. of Energy about 6 years back who claimed to be on Jason (he claimed to have been involved with resolving the "Morris worm" problem, which I seriously doubted since I'd been at Cornell when it was released and was very aware of how the spread of the worm was detected and stopped). This guy was at Los Alamos anyway and involved with the "behind-the-fence" computing environment there, so he could well have been a member of Jason. But I always wondered whether he'd been telling the truth on this one or not...
Seeing the various other posts along these lines...
My wife and I have used Linux on the desktop (a laptop at first) at home since 1993! Of coure, before that (and for a while after) we ran SunOS on an old Sun 3/50, which was immensely better, and actually cheaper (from a workstation reseller) than any of the PC's available in 1991. I've used SunOS, NextStep, Solaris, and now Linux (since 1999) on my work desktop since the late 1980's. And it just keeps getting better - the latest upgrade to RedHat 7.2 was the smoothest yet: an 11 minute install, plus about half an hour of futzing with KDE (I'd used Gnome at work before).
Some maybe we're weird - but I've never used Windows as a desktop, and never regretted it.
It's not 170 mm^2 but 170 mm X 170 mm, which is 17 cm x 17 cm, or a square about 6.5 inches on a side. Why is it people see "mm" and think small? Anyway as the article says, there are smaller ones out there...
We have a dozen or so secretarial types who use LaTeX every day and are very comfortable with it. Training a new person takes a few days - but we just sent some of these same people off to a class for MS Office, which is also taking several days out of their lives. Not really very much different. One thing about somebody with secretarial training is they know how to type VERY fast, so the point-and-click stuff doesn't seem to do much for them.
By the way, I delved into TeX's math font metrics recently. It's not that hard to mess around with them; there are several open-source programs for pfb/pfa/afm etc. conversion (it's been a few months so I don't remember all the details, but it only took me a couple hours on Google etc. to get it figured out). And have you tried doing ANYTHING similar with MS font formats?
So far in our experience - but planets are 3-dimensional structures with only a 2-dimensional surface we can live on, while artificial stations would presumably not generally be built to have 4000+ miles of uninhabitable basement; nor 10 miles of uninhabitable ceiling. Gaining that extra dimension of living space means space structures of admittedly large size would appear vastly bigger than planets to their inhabitants, and also to plain view if spread out two-dimensionally (which makes most sense from a solar-energy perspective), even while using only a tiny fraction of a planetary mass in construction.
Planets with a proper ecosystem naturally recycle the elements needed for life, mainly in our case, Oxygen and water.
Bring the ecosystem along - that was always the idea in O'Neill's vision, and there's nothing particularly special about a planetary surface for plant and animal life that seems impossible to duplicate in an artificial space structure.
While a 6 mile wide asteroid can cause serious damage to both space stations and planets, planets are pretty damn impervious to baseball sized rocks (of which in space there are many many more) where space stations can be quite devestated by them.
Actually, you wouldn't likely build a single monolithic station, you'd build thousands or millions of smaller "islands", each probably several miles away from the other. Even a six-mile asteroid hit would at most damage only a handful of these "islands", while it could devastate an entire planet. Think of the difference between a single mainframe and a Google-sized cluster of thousands of machines: you'll have more faults on the individual machines, but the whole structure will be far more resilient. Plus each station could be mobile enough to avoid major collisions (a lot easier than moving the asteroid itself - or the planet!) And there are lots of proposed ways of handling smaller collisions that wouldn't be terribly devastating. Cover the surface in lunar rubble/dust, for example, rather than solid metal, and you'll stop most medium-sized objects in just about the distance you need for radiation protection anyway.
Obviously all this is in reference to rather large-scale astro-engineering which we're nowhere close to right now - but maybe by the end of this century?
But we only live on the surface of the planet, which catches only a tiny fraction of the energy the sun makes available; in the long run there's a lot more room out there between the planets than on them, and I hear the view is spectacular...
Note that the survey was coordinated by the Planetary Society, not directly by NASA, and the Planetary Society has it's own (Carl Sagan memorial) agenda. The survey was at least a lot better than the typical "let me know whether you support or oppose the XXX program I have sponsored that brings world peace, tax cuts for all, and saves the global environment.." survey letters I get from my Congressman. But it could have been a lot better. A box to enter general comments would have been much appreciated, at the least.
While it's true we don't have anything that can lift what the Saturn-V could lift now, that's mainly because there's been no market for such massive launches in the last few decades. This proposal could open that market, but even without such heavy lifters the mission is quite doable. The way you do it is in-orbit assembly of the mission from smaller components - the Shuttle can lift about 1/4 of a Saturn-V, and Boeing's Delta-IV can lift a similar amount; there are several active proposals for a lunar return using a total of 4-5 launches to get the components and crew up there, and involving the construction of re-usable components - a lunar transfer vehicle for example which would act like the Apollo command module in a way, except never actually return to Earth but keep shuttling back and forth. And of course a permanent lunar base that could be developed and built upon heading toward long-term habitation.
Most of the costs in the Shuttle are sunk costs anyway, so the more missions that can be done with the Shuttle, the marginal costs per mission are actually not that big. That's not the way NASA and government accountants like to allocate costs though, which is part of NASA's problems with ISS... (and the recent directive to cut back even further in annual launches - while still paying the salaries of all those mission and support people...)
Anyway, before we do anything again with people we'll likely have a number of robotic lunar missions first. In fact a private one is coming up soon, and you can help it out and send along a personal memento (words or image) for just $20-30 or so: TransOrbital's TrailBlazer mission.
Uh... this is very wrong, but not obviously so I suppose the moderators can be forgiven. The reason for the cratering difference between the near and far sides of the Moon is ENTIRELY due to the fact that the near side is a slightly younger surface than the far side. You know all those dark "mare" areas you see on the near side? There are essentially none on the far side; what those are are lava flows dating back generally 3+ billion years, filling large basins created by giant impacts that mostly date back 3.9 billion years or more. Those mare lava flows covered over all the old craters, giving a somewhat smoother surface (by the way, if you look through a telescope at the Moon any time, near the terminator, you wouldn't ever again call it "silky smooth", anywhere).
In any case, the Moon does NOT act as a meteor shield for the Earth, in any significant way: the Moon's mass is only a little over 1% of that of Earth, it's cross-sectional area around 10%, and the Earth-Moon distance is so relatively huge that the chance of anything destined to hit the Moon also coming in a direction that it would have hit the Earth if the Moon wasn't there is somewhere around the 0.1% level - i.e. 99.9% of the meteors that hit the Moon wouldn't have gone anywhere near Earth anyway; and generally the Earth will receive about 10 times as many meteor hits as the Moon does, so the Moon shields a miniscule 0.01% or so of the ones that do hit.
Ok, so much for that theory. What about the rest of the post? Half the time the telescope would be unusable? That's sort of typical of telescopes actually - have you ever tried looking at the stars in daytime? In any case, one of the proposals mentioned was actually a polar observatory, in one of the craters that never receives any sunlight in the amazingly deep south pole basin. These are also shielded from Earth, and would be close to ideal 100% of the time - except they can only look south relative to our orbit around the sun, so somewhat over half the sky would be missing...
So it would be much more feasible to "place a radio telescope device with massive rfi shielding from the earth's noise out in deep space"? First consider the proposed size of these telescopes is huge - several km across! How do you propose to launch such a huge structure (the most massive parts of a lunar telescope would be constructed from in situ materials, and thus not require any launch from Earth)? How do you propose to launch the immensely more massive shielding? We're talking billions of tons here, when it costs $10,000 to launch a pound in the US these days?! Why is it that any time someone talks about the Moon these days it's a ridiculous proposal, but then the same people come up with immensely more hare-brained and expensive schemes!!!
"ask everyone to turn off the power for a few hours"!? I'm sure a few hours a year of telescope time (and remember they're dedicating some sort of Arecibo or bigger-size telescope to this) will really satisfy the astronomers... and what sort of totalitarian political system do you think the world would need to actually get a request like that followed?
Oh well, just had to respond to the +5 on the post...
L1 is between Earth and Moon, L2 is on the other side. Those positions are neutral, but unstable; however satellites can been kept in "halo" orbits around such unstable points for a long time with only relatively small fuel expenditure to keep them in the right position.
L1 and L2 are about 60,000 km above the lunar surface, if I recall correctly, so somewhat further away than geo-synchronous orbits from Earth, but they would serve a similar purpose for lunar communications. L2 is the most logical for communicating with a far side observatory; laying several thousand km of cable that has to withstand 400 degree temperature swings could get rather expensive.
Re:Used up in the cost to get the electricity, tho
on
Magnetic Space Launches
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· Score: 3, Informative
Definitely doesn't need to be vertical - you're out of half the atmosphere in 7 miles, out of over 99% of the atmosphere by 50 miles high, and by that point the velocity you need to get to orbit needs to be horizontal, not vertical; you still need some vertical thrust to counteract gravity of course, the main point is there's an optimal thrust/weight ratio beyond the atmosphere that is also associated with a specific curved trajectory, far from vertical...
The ZDNet article mentions a fuel cell being developed by NEC using nanotechnology to process the methane, with 10 times the energy density of current lithium batteries - anybody know what that is about? I'd guess it was wild blue-sky stuff that won't be available for decades, except that I used to know somebody who worked at NEC research in the US, and they seemed pretty serious about practical applications of research.
Alright, maybe I posted a little too soon, but shouldn't "flamebait" be attracting flaming responses? I don't see any...
Anyway, if I'd spent a little more time thinking about the advice side of it, taking a look at appropriate programming methodologies (like Extreme Programming advocated in another thread here) would be one piece I'd advocate. Given the size of the code (1 MB = about 20-30,000 lines?) there's no need for major heavy-weight processes here. More important I'd say is sitting down and figuring out in the appropriate level of detail what exactly your system is doing right now - you can do this using UML diagrams which seems to be becoming a standard, though the main use we've found is to try to get an overall view of things which we then throw out when we get into the details again.
The other thing to do along these lines is look for your use of standard patterns within your code - the Design Patterns book is extremely helpful if you're moving to an object-oriented framework at all; following well-known patterns and indicating clearly what you are doing can make your code much easier for others to follow.
we're doing something similar - and switching to java (JSP's + Tomcat, struts) to replace a lot of old perl cgi's. The java code is much, much cleaner. But object-oriented perl code can help if you don't want to take the plunge too far into a new language. And at least find a way to go mod_perl rather than CGI, for the things where performance matters at all.
You start combining the elements of course. 100x99x98/6 is about 160,000, which is the number of different combinations of 3 elements you can have. But then you can also continually adjust their relative concentrations - A B_x C_y allowing x and y to be any number between 0 and infinity - in practice you might sample at 10 different points in x and y to get a rough idea: that's another factor of 100, so about 10 million ways to combine three elements just in terms of chemistry. Go look at alloy phase diagram books for a sample of the complexity you can get combining three metallic elements into alloys. And why stop at 3 elements? The high T_c superconductors take 4 or 5 or more to work.
But this isn't just chemistry either - the material is nonuniform, layered. Each layer can be composed of some different magnetic or non-magnetic alloy, and each layer can have a different thickness, and the number of layers is itself a variable. The combinatorial possibilities are in the billions! Obviously they narrowed it down considerably to find what they needed in just 30,000 samples - but there may be something even more spectacular out there among the billions of other possibilities, just waiting to be found.
That's what makes science these days so interesting:-) And so difficult:-(
I remember first reading about these in some physics articles in about 1991 or 1992; we had a presentation from one of our colleagues on the underlying physics about then. The commercial companies really jumped on it to bring these out so quickly! The only other case I can recall of such quick and major deployment of a basic discovery was when the Erbium-doped fiber amplifiers came out, within a year or so of the discovery of Erbium's ability to amplify optical signals; this is why we can double capacity on optical fibers with ease now, even trans-oceanic cables, just by changing the equipment on the ends, and is one of the major reasons for the rapid increases in bandwidth capacity of the last few years (getting the telco's to actually release that bandwidth for a reasonable price is another story of course...)
Re:This is a weapon of massless destruction
on
Lunar Lasers
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· Score: 2
Microwave mesh antenna is a lot cheaper than solar collectors on earth for same area.
One other advantage of space-based telescopes (not realized by Hubble since it's so close to Earth) is the much longer observing times you can have, viewing a region of the sky for possible days at a time. On Earth's surface you're limited to night-time observations, but in space pointing away from the Sun it's always night.
The trick could be to use the gradual decrease in beam intensity as you move to the outer portions of the beam, and send this information back to the other satelite to re-adjust.
Yeah, I was thinking of the same technique - once you have the communications link up also, you could use the same directional information to transmit power also, something that's been proposed as a way to make use of Solar Power Satellites. This is a very important accomplishment!
The standard resource for free scientific software (unfortunately mostly written in Fortran) is Jack Dongarra's netlib: http://www.netlib.org/
It's best in linear algebra (matrix problems etc) but there's other good stuff in there - FFT routines, statistical stuff, some deep mathematics, and more... Also, not free, but good, is the standby Numerical Recipes book, which includes source code for a large variety of uses, particularly solution of nonlinear optimization problems.
Other stuff is available free from the supercomputer centers - at least they used to give stuff away free, though NCSA at least seems to have tried to make money off their things lately...
Huh? Was this an attempt at humor? I thought the '^' character for "vector" operations was a wonderful idea for perl... Even FORTRAN has had this sort of capability since FORTRAN-90 came out... If you don't want to use the '^' then fine, use some complicated map or looping construct. But I'd pick the '^' any day over those other suggestions!
First, think about how long you mind being "behind the news". If you're ok with learning about things up to a week late (which is plenty for most people not directly affected by an event), subscribe to a reliable newsmagazine (I happen to like Newsweek) and read only that. And rely on your friends and neighbors to tell you of anything else that's important going on. This way you'll avoid worrying about a lot of rumors or temporary issues that really don't merit your attention. If you need to be a bit more up-to-date, pick a daily paper, or a daily time to read a news web site, watch TV or listen to the radio, and stick to it.
Hardly anybody needs to be constantly updated on the news more often than that. Sure there are times when it's nice to track an event as it happens. We were all listening to radios or watching TV Tuesday morning. But beyond the first few hours, unless you're directly involved somehow, break it off and go back to your normal news habits. You'll find yourself a lot better off.
The alternatives are, let's see, Bismuth-strontium-calcium-copper-oxide, or perhaps one of the mercury intercalated copper oxides, or yttrium-barium-copper oxide. Hmmm. Bismuth, mercury, barium are all pretty toxic. I was in a lab where they were working with thalium superconducting compounds, and one day some clueless undergrad dropped a chunk and spread it around - thalium is among the worst of the heavy metals... At least with the organics theres a hope that some chemists will come up with non-toxic versions that work as well. But we don't have a candidate high-Tc superconductor around right now that you would actually want to eat dinner off of.
I've always had great respect for a few tech journals - Sun Expert (now S/W Expert) has always had excellent articles that seemed relevant to issues we were looking at at the time - maybe because the articles were written by regular users (sys admins, people who did software development for a living) rather than "journalists". "Software Development" seems to have similar integrity. But I guess that's not what this guy was ranting about...
Slashdot Mirror
How public are/were the Jason members? I met somebody from the Dept. of Energy about 6 years back who claimed to be on Jason (he claimed to have been involved with resolving the "Morris worm" problem, which I seriously doubted since I'd been at Cornell when it was released and was very aware of how the spread of the worm was detected and stopped). This guy was at Los Alamos anyway and involved with the "behind-the-fence" computing environment there, so he could well have been a member of Jason. But I always wondered whether he'd been telling the truth on this one or not...
Seeing the various other posts along these lines...
My wife and I have used Linux on the desktop (a laptop at first) at home since 1993! Of coure, before that (and for a while after) we ran SunOS on an old Sun 3/50, which was immensely better, and actually cheaper (from a workstation reseller) than any of the PC's available in 1991. I've used SunOS, NextStep, Solaris, and now Linux (since 1999) on my work desktop since the late 1980's. And it just keeps getting better - the latest upgrade to RedHat 7.2 was the smoothest yet: an 11 minute install, plus about half an hour of futzing with KDE (I'd used Gnome at work before).
Some maybe we're weird - but I've never used Windows as a desktop, and never regretted it.
It's not 170 mm^2 but 170 mm X 170 mm, which is 17 cm x 17 cm, or a square about 6.5 inches on a side. Why is it people see "mm" and think small? Anyway as the article says, there are smaller ones out there...
We have a dozen or so secretarial types who use LaTeX every day and are very comfortable with it. Training a new person takes a few days - but we just sent some of these same people off to a class for MS Office, which is also taking several days out of their lives. Not really very much different. One thing about somebody with secretarial training is they know how to type VERY fast, so the point-and-click stuff doesn't seem to do much for them.
By the way, I delved into TeX's math font metrics recently. It's not that hard to mess around with them; there are several open-source programs for pfb/pfa/afm etc. conversion (it's been a few months so I don't remember all the details, but it only took me a couple hours on Google etc. to get it figured out). And have you tried doing ANYTHING similar with MS font formats?
So far in our experience - but planets are 3-dimensional structures with only a 2-dimensional surface we can live on, while artificial stations would presumably not generally be built to have 4000+ miles of uninhabitable basement; nor 10 miles of uninhabitable ceiling. Gaining that extra dimension of living space means space structures of admittedly large size would appear vastly bigger than planets to their inhabitants, and also to plain view if spread out two-dimensionally (which makes most sense from a solar-energy perspective), even while using only a tiny fraction of a planetary mass in construction.
Bring the ecosystem along - that was always the idea in O'Neill's vision, and there's nothing particularly special about a planetary surface for plant and animal life that seems impossible to duplicate in an artificial space structure.
Actually, you wouldn't likely build a single monolithic station, you'd build thousands or millions of smaller "islands", each probably several miles away from the other. Even a six-mile asteroid hit would at most damage only a handful of these "islands", while it could devastate an entire planet. Think of the difference between a single mainframe and a Google-sized cluster of thousands of machines: you'll have more faults on the individual machines, but the whole structure will be far more resilient. Plus each station could be mobile enough to avoid major collisions (a lot easier than moving the asteroid itself - or the planet!) And there are lots of proposed ways of handling smaller collisions that wouldn't be terribly devastating. Cover the surface in lunar rubble/dust, for example, rather than solid metal, and you'll stop most medium-sized objects in just about the distance you need for radiation protection anyway.
Obviously all this is in reference to rather large-scale astro-engineering which we're nowhere close to right now - but maybe by the end of this century?
But we only live on the surface of the planet, which catches only a tiny fraction of the energy the sun makes available; in the long run there's a lot more room out there between the planets than on them, and I hear the view is spectacular...
Note that the survey was coordinated by the Planetary Society, not directly by NASA, and the Planetary Society has it's own (Carl Sagan memorial) agenda. The survey was at least a lot better than the typical "let me know whether you support or oppose the XXX program I have sponsored that brings world peace, tax cuts for all, and saves the global environment.." survey letters I get from my Congressman. But it could have been a lot better. A box to enter general comments would have been much appreciated, at the least.
While it's true we don't have anything that can lift what the Saturn-V could lift now, that's mainly because there's been no market for such massive launches in the last few decades. This proposal could open that market, but even without such heavy lifters the mission is quite doable. The way you do it is in-orbit assembly of the mission from smaller components - the Shuttle can lift about 1/4 of a Saturn-V, and Boeing's Delta-IV can lift a similar amount; there are several active proposals for a lunar return using a total of 4-5 launches to get the components and crew up there, and involving the construction of re-usable components - a lunar transfer vehicle for example which would act like the Apollo command module in a way, except never actually return to Earth but keep shuttling back and forth. And of course a permanent lunar base that could be developed and built upon heading toward long-term habitation.
Most of the costs in the Shuttle are sunk costs anyway, so the more missions that can be done with the Shuttle, the marginal costs per mission are actually not that big. That's not the way NASA and government accountants like to allocate costs though, which is part of NASA's problems with ISS... (and the recent directive to cut back even further in annual launches - while still paying the salaries of all those mission and support people...)
Anyway, before we do anything again with people we'll likely have a number of robotic lunar missions first. In fact a private one is coming up soon, and you can help it out and send along a personal memento (words or image) for just $20-30 or so: TransOrbital's TrailBlazer mission.
Uh... this is very wrong, but not obviously so I suppose the moderators can be forgiven. The reason for the cratering difference between the near and far sides of the Moon is ENTIRELY due to the fact that the near side is a slightly younger surface than the far side. You know all those dark "mare" areas you see on the near side? There are essentially none on the far side; what those are are lava flows dating back generally 3+ billion years, filling large basins created by giant impacts that mostly date back 3.9 billion years or more. Those mare lava flows covered over all the old craters, giving a somewhat smoother surface (by the way, if you look through a telescope at the Moon any time, near the terminator, you wouldn't ever again call it "silky smooth", anywhere).
In any case, the Moon does NOT act as a meteor shield for the Earth, in any significant way: the Moon's mass is only a little over 1% of that of Earth, it's cross-sectional area around 10%, and the Earth-Moon distance is so relatively huge that the chance of anything destined to hit the Moon also coming in a direction that it would have hit the Earth if the Moon wasn't there is somewhere around the 0.1% level - i.e. 99.9% of the meteors that hit the Moon wouldn't have gone anywhere near Earth anyway; and generally the Earth will receive about 10 times as many meteor hits as the Moon does, so the Moon shields a miniscule 0.01% or so of the ones that do hit.
Ok, so much for that theory. What about the rest of the post? Half the time the telescope would be unusable? That's sort of typical of telescopes actually - have you ever tried looking at the stars in daytime? In any case, one of the proposals mentioned was actually a polar observatory, in one of the craters that never receives any sunlight in the amazingly deep south pole basin. These are also shielded from Earth, and would be close to ideal 100% of the time - except they can only look south relative to our orbit around the sun, so somewhat over half the sky would be missing...
So it would be much more feasible to "place a radio telescope device with massive rfi shielding from the earth's noise out in deep space"? First consider the proposed size of these telescopes is huge - several km across! How do you propose to launch such a huge structure (the most massive parts of a lunar telescope would be constructed from in situ materials, and thus not require any launch from Earth)? How do you propose to launch the immensely more massive shielding? We're talking billions of tons here, when it costs $10,000 to launch a pound in the US these days?! Why is it that any time someone talks about the Moon these days it's a ridiculous proposal, but then the same people come up with immensely more hare-brained and expensive schemes!!!
"ask everyone to turn off the power for a few hours"!? I'm sure a few hours a year of telescope time (and remember they're dedicating some sort of Arecibo or bigger-size telescope to this) will really satisfy the astronomers... and what sort of totalitarian political system do you think the world would need to actually get a request like that followed?
Oh well, just had to respond to the +5 on the post...
L1 is between Earth and Moon, L2 is on the other side. Those positions are neutral, but unstable; however satellites can been kept in "halo" orbits around such unstable points for a long time with only relatively small fuel expenditure to keep them in the right position.
L1 and L2 are about 60,000 km above the lunar surface, if I recall correctly, so somewhat further away than geo-synchronous orbits from Earth, but they would serve a similar purpose for lunar communications. L2 is the most logical for communicating with a far side observatory; laying several thousand km of cable that has to withstand 400 degree temperature swings could get rather expensive.
Definitely doesn't need to be vertical - you're out of half the atmosphere in 7 miles, out of over 99% of the atmosphere by 50 miles high, and by that point the velocity you need to get to orbit needs to be horizontal, not vertical; you still need some vertical thrust to counteract gravity of course, the main point is there's an optimal thrust/weight ratio beyond the atmosphere that is also associated with a specific curved trajectory, far from vertical...
The ZDNet article mentions a fuel cell being developed by NEC using nanotechnology to process the methane, with 10 times the energy density of current lithium batteries - anybody know what that is about? I'd guess it was wild blue-sky stuff that won't be available for decades, except that I used to know somebody who worked at NEC research in the US, and they seemed pretty serious about practical applications of research.
Alright, maybe I posted a little too soon, but shouldn't "flamebait" be attracting flaming responses? I don't see any...
Anyway, if I'd spent a little more time thinking about the advice side of it, taking a look at appropriate programming methodologies (like Extreme Programming advocated in another thread here) would be one piece I'd advocate. Given the size of the code (1 MB = about 20-30,000 lines?) there's no need for major heavy-weight processes here. More important I'd say is sitting down and figuring out in the appropriate level of detail what exactly your system is doing right now - you can do this using UML diagrams which seems to be becoming a standard, though the main use we've found is to try to get an overall view of things which we then throw out when we get into the details again.
The other thing to do along these lines is look for your use of standard patterns within your code - the Design Patterns book is extremely helpful if you're moving to an object-oriented framework at all; following well-known patterns and indicating clearly what you are doing can make your code much easier for others to follow.
we're doing something similar - and switching to java (JSP's + Tomcat, struts) to replace a lot of old perl cgi's. The java code is much, much cleaner. But object-oriented perl code can help if you don't want to take the plunge too far into a new language. And at least find a way to go mod_perl rather than CGI, for the things where performance matters at all.
Check our statistics - Linux has been holding steady at about 16-17% of our user base since the end of 1999.
You start combining the elements of course. 100x99x98/6 is about 160,000, which is the number of different combinations of 3 elements you can have. But then you can also continually adjust their relative concentrations - A B_x C_y allowing x and y to be any number between 0 and infinity - in practice you might sample at 10 different points in x and y to get a rough idea: that's another factor of 100, so about 10 million ways to combine three elements just in terms of chemistry. Go look at alloy phase diagram books for a sample of the complexity you can get combining three metallic elements into alloys. And why stop at 3 elements? The high T_c superconductors take 4 or 5 or more to work.
:-) And so difficult :-(
But this isn't just chemistry either - the material is nonuniform, layered. Each layer can be composed of some different magnetic or non-magnetic alloy, and each layer can have a different thickness, and the number of layers is itself a variable. The combinatorial possibilities are in the billions! Obviously they narrowed it down considerably to find what they needed in just 30,000 samples - but there may be something even more spectacular out there among the billions of other possibilities, just waiting to be found.
That's what makes science these days so interesting
I remember first reading about these in some physics articles in about 1991 or 1992; we had a presentation from one of our colleagues on the underlying physics about then. The commercial companies really jumped on it to bring these out so quickly! The only other case I can recall of such quick and major deployment of a basic discovery was when the Erbium-doped fiber amplifiers came out, within a year or so of the discovery of Erbium's ability to amplify optical signals; this is why we can double capacity on optical fibers with ease now, even trans-oceanic cables, just by changing the equipment on the ends, and is one of the major reasons for the rapid increases in bandwidth capacity of the last few years (getting the telco's to actually release that bandwidth for a reasonable price is another story of course...)
Microwave mesh antenna is a lot cheaper than solar collectors on earth for same area.
One other advantage of space-based telescopes (not realized by Hubble since it's so close to Earth) is the much longer observing times you can have, viewing a region of the sky for possible days at a time. On Earth's surface you're limited to night-time observations, but in space pointing away from the Sun it's always night.
Yeah, I was thinking of the same technique - once you have the communications link up also, you could use the same directional information to transmit power also, something that's been proposed as a way to make use of Solar Power Satellites. This is a very important accomplishment!
The standard resource for free scientific software (unfortunately mostly written in Fortran) is Jack Dongarra's netlib: http://www.netlib.org/
It's best in linear algebra (matrix problems etc) but there's other good stuff in there - FFT routines, statistical stuff, some deep mathematics, and more... Also, not free, but good, is the standby Numerical Recipes book, which includes source code for a large variety of uses, particularly solution of nonlinear optimization problems.
Other stuff is available free from the supercomputer centers - at least they used to give stuff away free, though NCSA at least seems to have tried to make money off their things lately...
Huh? Was this an attempt at humor? I thought the '^' character for "vector" operations was a wonderful idea for perl... Even FORTRAN has had this sort of capability since FORTRAN-90 came out... If you don't want to use the '^' then fine, use some complicated map or looping construct. But I'd pick the '^' any day over those other suggestions!
First, think about how long you mind being "behind the news". If you're ok with learning about things up to a week late (which is plenty for most people not directly affected by an event), subscribe to a reliable newsmagazine (I happen to like Newsweek) and read only that. And rely on your friends and neighbors to tell you of anything else that's important going on. This way you'll avoid worrying about a lot of rumors or temporary issues that really don't merit your attention. If you need to be a bit more up-to-date, pick a daily paper, or a daily time to read a news web site, watch TV or listen to the radio, and stick to it.
Hardly anybody needs to be constantly updated on the news more often than that. Sure there are times when it's nice to track an event as it happens. We were all listening to radios or watching TV Tuesday morning. But beyond the first few hours, unless you're directly involved somehow, break it off and go back to your normal news habits. You'll find yourself a lot better off.
The alternatives are, let's see, Bismuth-strontium-calcium-copper-oxide, or perhaps one of the mercury intercalated copper oxides, or yttrium-barium-copper oxide. Hmmm. Bismuth, mercury, barium are all pretty toxic. I was in a lab where they were working with thalium superconducting compounds, and one day some clueless undergrad dropped a chunk and spread it around - thalium is among the worst of the heavy metals... At least with the organics theres a hope that some chemists will come up with non-toxic versions that work as well. But we don't have a candidate high-Tc superconductor around right now that you would actually want to eat dinner off of.
I've always had great respect for a few tech journals - Sun Expert (now S/W Expert) has always had excellent articles that seemed relevant to issues we were looking at at the time - maybe because the articles were written by regular users (sys admins, people who did software development for a living) rather than "journalists". "Software Development" seems to have similar integrity. But I guess that's not what this guy was ranting about...