...so the ping times from one side to the other would be 200,000 years Here, you're assuming that messages and communication has to be two-way. There are a number of really good reasons why one-way broadcasts would be a desirable means of communication.
Here are a couple of scenarios I can think of: 1) Regular status-updates on your local corner of the galaxy. This isn't a strange idea, think of those multi-page holiday update letters you get from distant relatives each year. 2) Announcing the arrival and successful colonization of a new stellar system/neighborhood. The analogy here is the announcement of the arrival of a new baby. 3) Warnings. If you are invaded by a hostile group, you might send out something akin to a warning to allies to cease communications or develop their own defenses. Your message, at least, is likely to get their before the hostile group. 4) Scientific bulletins. Though there's bound to be some duplication, significant discoveries and advancements would definitely be worth sending over the neutrino-wire.
Of course there are many more, and many that none of us could envision because we don't have the experience of maintaining a galactic civilization.
Good grief, from the number of "this isn't a Mesh" posts, it seems like no one is aware that the word "mesh" has a plain-English meaning. That's the great thing about context. When you read the summary, and then TFA, and you don't see mesh, you should think "Oh, they meant mesh in the sense of joining".
Just because a word has a technical meaning for branding purposes, the plain-English meaning isn't somehow superseded or obsolete.
The title of the slashdot article refers to the plain-english use of the word mesh, as in to join two things together for one purpose. This was obvious both in context and in that the word "mesh" was used as a verb. Mesh networking is a noun.
Composites are significantly different from metal structures in that their primary failure modes are not fatigue related microfractures, but a phenomenon called delamination in which static and dynamic loading can cause the layers of alternating orientation fibers to separate. It could very well be that in order to design a wing that was not susceptible to delamination, the wing turned out to be incredibly flexible.
It sounds as if Boeing uses a "factor of safety" of 1.5, where the maximum anticipated load is multiplied by the factor of safety to determine the design strength of the wing. The factor of safety is calculated based on the earliest failure mode of the part, so it could simply be that other failure modes than wing deformation and buckling (as seen in the youtube video) are what determines the factor of safety with this new carbon fiber wing.
I'm not entirely positive what causes the difference, but it has something to do with minimizing the so-called "delta-V" or change in velocity (and thus amount of fuel burned) required to get from point A to point B in space. Those numbers come from Robert Zubrin's "Case for Mars", and use a modified Hohmann Transfer orbit.
But, thinking more about your answer, you're actually moving "up" the Sun's gravity well on the way there and "down" it on the way back...though the analogy doesn't go any further than that I guess.
There is no significant funding for human exploration of Mars, nothing that even registers on the FY 2008 budget highlights. There might be a few relatively small grants to develop next generation spacesuits, but those will be useful on the Moon, too, so they won't be affected.
This isn't then an appropriate response to a fiscally unsound endeavor by a careful legislature. It's a gesture that the Congress will not support the President's Vision for Space Exploration in its entirety.
But, this language has the capability to significantly delay an eventual human mission to Mars if it's passed. It will force NASA to view the Moon as its ultimate objective, rather than as a stepping stone to Mars and beyond, as envisioned by the President.
Whether this is a good thing is up to debate, but I am inclined to believe that this empty gesture has great potential for unintended consequences further down the road.
Re:Think about what the plants need...
on
Vertical Farming
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· Score: 1
I can't disagree with you there, I don't think you can get more energy by the Sunlight->PV->Electricity->Artificial Light path either, even if you somehow emit only frequencies that plants absorb with 90% efficiency or something like that. I just wanted to clear up the plants vs. PV efficiency issue.
What might be of a benefit is that most of the time, sun is striking the building obliquely, and thus providing more than the rooftop surface area of light. So, this might help light other floors as well.
Plants are more efficient than solar cells. Actually, that's not true. According to this page from a professor at UIUC, plants range from 0.1% to 8% (rare) efficiency in converting energy to sunlight. Most crops are between 1 and 2%.
Typical silicon photovoltaic cells, by contrast range between 6% and 16% efficient, with most commercially-installed panels being in the range of 12-16%.
Research is ongoing in increasing the efficiency and lowering cost. There are 30-40% efficient panels available, they're just way too expensive at this time for anything other than satellites or space stations.
No, what I'm saying is that they should simulate a more realistic mission profile/timeline. 17 months of almost continual confinement to a small ship will be dismal. In fact, any long simulation like this without the firm knowledge that it will greatly contribute to our success in an eventual mission would be dismal.
If they had a couple of years to explore a simulated Mars environment (as is the plan currently) in between arrival and the return journey, they would have some relief.
Virtually all modern plans for Mars missions follow the same basic timeline: 6 months travel to Mars, 2 years on the planet, and 8 months back. The idea of a 30-day stay on the planet was abandoned long ago by NASA.
This simulation takes away the huge reward of the long travel time, and replaces it with a brief 30 day stint of freedom.
They'll surely get interesting results, they just won't be worth anything when it comes time to actually plan a real manned Mars mission.
bcg, This looks really interesting, and using BitTorrent in tandem with a distributed computing queue scheduler (like XGrid, in the case of OMG) could provide not only the ability to effectively distribute coarse-grained tasks, but also efficiently share large input datasets for each process.
The comments so far have (mostly) overlooked the main point of just why the OpenMacGrid is different: it's *open*. That means that scientists, even PhD students like myself that want to run jobs using far greater numbers of nodes than the clusters (beowolf or otherwise) at our home institutions will now have a means to do so. Most such projects have neither the resources nor the capabilities to create their own custom cross-platform clients like those mentioned from other distributed computing projects.
OpenMacGrid (or just OMG, I guess) uses XGrid, which is built-in to every OSX 10.4 distribution and acts just like any other job queue manager, except it's even easier. So, the whole process of writing a distributed computing project becomes far simpler as well.
Finally, the OMG it doesn't matter if the OMG is cross-platform running on proprietary hardware: so is every other cluster that I as a scientist have ever had access to. The SGI cluster is proprietary, and to an extent so is the Linux machine at our High-Performance Computing lab on campus. And, if you're thinking about it being non-cross-platform from the client side, well, you're probably not thinking differently anyway, so just go download Folding@Home.
I don't know that China's space program is a sign of top-down economic planning, because largely the "communist" govenerment is no longer in control of the economy. They seem to be persuing a space program from the standpoint of national pride, perhaps exclusively. If you have a country of more than a billion people and can inspire them to work harder and be more loyal by building a few rockets, wouldn't you do it?
Unfortunately the US is not light-years ahead in biotech, especially stem-cell science. Any differences between our countries in science or technology will not last much longer, because they graduate so very many more scientists and engineers than we do. Granted, our colleges are the envy of the world, but increasingly foreign students are staying home and expending their genius there. This is why Tom Friedman and so many others are talking about how the world is now flattening even for knowledge workers, like scientists.
Actually, this little device could serve a purpose for me: 1) I live in an apartment small enough for the bluetooth signal to propogate easily throughout 2) I have no home telephone 3) I have occasional desire to speak at length with friends and family, but am somewhat limited by the expense of high-minute cell plans 4) Skype offers a call-forwarding plan that routes calls to other phones if unanswered on your computer
The net result is, for a small fee, I could have a "home" telephone number that anyone could call, and if I am within range of the bluetooth, it would ring my cellphone that way. But, if I'm not there, the call would be forwarded to my cellphone. Thus, with a single number, and a single phone, I would be reachable easily and probably much more cheaply than with a cellphone alone.
What Michael did was real reporting, believe it or not. He looked up the group that was sponsoring this conference and found that they were an industry-friendly group of scientists and "others" with a vested interest in seeding doubt of the Global Warming hypothesis.
Any tremendously complex system is hard to understand key aspects of, but the evidence I've seen (such as the plots of CO2 concentrations vs temperature), the systems modeling I've done, and the exhaustive global modeling done by hundreds of scientists around the world supports this key aspect of global warming: we are its cause.
As for everyone saying that money is holding GW scientists enthralled, don't you think that the oil companies (and US governemnt) would love to pay for studies disputing GW? There is not that much money in GW research; the total is probably somewhere in the few billions. The oil companies spend far more than that every year on finding new ways to pump more oil.
There is no serious scientific doubt that we are causing GW, and kudos to the/. editor for looking deeper than some corporate PR for a story.
Equal weight would be given if the scientists who doubt global warming got to talk as much as those who see it in their science every day. If such equality were granted that BBC article would have given about two words to the "skeptics" conference, and the rest of the article would have been about real science.
Granting equality to fundamentally unequal propositions is ridiculous and counter-productive. The weight of evidence accumulated by serious, diligent scientists that demonstrates global warming is real would bury the doubting voices--almost always sponsored by interests opposed to environmental regulation.
As long as we are talking about spending taxpayer dollars, what is the social benefit repealing the estate tax? This will remove hundreds of billions from the nation's coffers, and could easily fund manned space exploration!
At least manned space exploration money funds jobs, pays for research and provides every American a source of pride. Other methods of squandering public funds like repealing the estate tax only serve to promote aristocracy, increase debt servicing costs (via increasing deficits), and widen the gulf between the richest and poorest in our country
Re:But didn't you hear?
on
XBox Released
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· Score: 1
I hate to be the one to point out to you that you completely missed the sarcasm of the post you responded to. Great observation skills!
How is a "lead in the space race" important at all? What does it matter if China puts a man on the moon?
Space is not some forum for inter-nation political posturing (which it was during the Cold War). If you
want to know why the US doesn't have an "unassailable" lead in the space race, it's because the space race
is over.
If China puts a man on the moon, then there's one more country that has the capabilities and know-how to launch
people into orbit. Now, we need to privatize that knowledge as well so corporations can get in on the game.
As soon as space launches become affordable (which would mean US$10/kg rather than US$1000/kg), then the world
can start using space for what it should be, additional space for the expansion of human life and enterprise.
Political posturing is a needless waste of taxpayers' money. Most people don't see the point in spending money
on the space program, so let corporations do it instead. They will do it better, more quickly, and, in the end,
more to everyone's benefit than NASA ever could.
you never get more energy from hydrogen than you put in
Herein lies the biggest problem facing the environment and enviromentalists today. People
believe that solar, wind and hydroelectric power are "alternative" sources of energy. However,
these, along with geothermal energy are the only sources of energy available to our planet.
Fossil fuels were not deposited beneath the surface of the Earth like Uranium was. They were created
by life which is powered by the sun, wind, and geothermal heat. Fossil fuels took millions of years to be
produced and exist in only a limited supply and are found in currently very unstable regions of the world.
By burning these fuels we are doing the exact same thing that we would be doing by using Hydrogen in fuel cells.
We are releasing stored energy that was provided initially by "alternative" energy sources. So, in effect,
using hydrogen as a source of power for fuel cells would be the same thing as burning fossil fuels, but would
instead be more efficient, potentially more profitable, strategically advantageous (no middle east allies to worry about)
and would be indefinitely sustainable.
People bitch about Microsoft because it's an anti-competitive monopolist that squashes real innovation while pushing its corporate-oriented pablum on the masses.
Apple is proprietary, true, but it provides products that users really enjoy to use, and is constantly innovating.
first, does the machine do different typographic styles and layouts
Just like most existing laser printers it could be configured to accept a huge variety of fonts provided by the publisher. The necessary fonts could even be included in the book's files.
standard copier paper is usually considerably worse...
Within a certain range, I am sure that the machine could be configured to use different weights and finishes.
don't forget the rest of the experience you would thus forgo...
On the contrary, bookstores would no longer have to stock multiple copies of individual books so they could have thousands and thousands of singly printed books available for the browsing! Think of how much of a bookstores shelfspace is dominated by 15-20 copies of the new Danielle Steel novel, etc.
Also, by using the machine overnight to print multiple copies of popular books, waiting times could be reduced dramatically. This machine seems to be an incredibly good idea, and I believe has very few drawbacks. It would enhance the typical browsing experience, cut costs to the publishers, enhance selection, allow greater access for new authors, and (presumably) save resources as well.
Slashdot Mirror
No need to bother a million Slashdot readers.
It's hardly a bother, I had no idea how to answer his question (as I'm sure most readers don't). Instead, I was interested in the answers.
Even if I went through the Google I'd still want to ask Slashdot and the expertise here.
...so the ping times from one side to the other would be 200,000 years Here, you're assuming that messages and communication has to be two-way. There are a number of really good reasons why one-way broadcasts would be a desirable means of communication.Here are a couple of scenarios I can think of:
1) Regular status-updates on your local corner of the galaxy. This isn't a strange idea, think of those multi-page holiday update letters you get from distant relatives each year.
2) Announcing the arrival and successful colonization of a new stellar system/neighborhood. The analogy here is the announcement of the arrival of a new baby.
3) Warnings. If you are invaded by a hostile group, you might send out something akin to a warning to allies to cease communications or develop their own defenses. Your message, at least, is likely to get their before the hostile group.
4) Scientific bulletins. Though there's bound to be some duplication, significant discoveries and advancements would definitely be worth sending over the neutrino-wire.
Of course there are many more, and many that none of us could envision because we don't have the experience of maintaining a galactic civilization.
Good grief, from the number of "this isn't a Mesh" posts, it seems like no one is aware that the word "mesh" has a plain-English meaning. That's the great thing about context. When you read the summary, and then TFA, and you don't see mesh, you should think "Oh, they meant mesh in the sense of joining".
Just because a word has a technical meaning for branding purposes, the plain-English meaning isn't somehow superseded or obsolete.
The title of the slashdot article refers to the plain-english use of the word mesh, as in to join two things together for one purpose. This was obvious both in context and in that the word "mesh" was used as a verb. Mesh networking is a noun.
Composites are significantly different from metal structures in that their primary failure modes are not fatigue related microfractures, but a phenomenon called delamination in which static and dynamic loading can cause the layers of alternating orientation fibers to separate. It could very well be that in order to design a wing that was not susceptible to delamination, the wing turned out to be incredibly flexible.
It sounds as if Boeing uses a "factor of safety" of 1.5, where the maximum anticipated load is multiplied by the factor of safety to determine the design strength of the wing. The factor of safety is calculated based on the earliest failure mode of the part, so it could simply be that other failure modes than wing deformation and buckling (as seen in the youtube video) are what determines the factor of safety with this new carbon fiber wing.
I'm not entirely positive what causes the difference, but it has something to do with minimizing the so-called "delta-V" or change in velocity (and thus amount of fuel burned) required to get from point A to point B in space. Those numbers come from Robert Zubrin's "Case for Mars", and use a modified Hohmann Transfer orbit.
But, thinking more about your answer, you're actually moving "up" the Sun's gravity well on the way there and "down" it on the way back...though the analogy doesn't go any further than that I guess.
There is no significant funding for human exploration of Mars, nothing that even registers on the FY 2008 budget highlights. There might be a few relatively small grants to develop next generation spacesuits, but those will be useful on the Moon, too, so they won't be affected.
This isn't then an appropriate response to a fiscally unsound endeavor by a careful legislature. It's a gesture that the Congress will not support the President's Vision for Space Exploration in its entirety.
But, this language has the capability to significantly delay an eventual human mission to Mars if it's passed. It will force NASA to view the Moon as its ultimate objective, rather than as a stepping stone to Mars and beyond, as envisioned by the President.
Whether this is a good thing is up to debate, but I am inclined to believe that this empty gesture has great potential for unintended consequences further down the road.
I can't disagree with you there, I don't think you can get more energy by the Sunlight->PV->Electricity->Artificial Light path either, even if you somehow emit only frequencies that plants absorb with 90% efficiency or something like that. I just wanted to clear up the plants vs. PV efficiency issue.
What might be of a benefit is that most of the time, sun is striking the building obliquely, and thus providing more than the rooftop surface area of light. So, this might help light other floors as well.
Typical silicon photovoltaic cells, by contrast range between 6% and 16% efficient, with most commercially-installed panels being in the range of 12-16%.
Research is ongoing in increasing the efficiency and lowering cost. There are 30-40% efficient panels available, they're just way too expensive at this time for anything other than satellites or space stations.
No, what I'm saying is that they should simulate a more realistic mission profile/timeline. 17 months of almost continual confinement to a small ship will be dismal. In fact, any long simulation like this without the firm knowledge that it will greatly contribute to our success in an eventual mission would be dismal.
If they had a couple of years to explore a simulated Mars environment (as is the plan currently) in between arrival and the return journey, they would have some relief.
Virtually all modern plans for Mars missions follow the same basic timeline: 6 months travel to Mars, 2 years on the planet, and 8 months back. The idea of a 30-day stay on the planet was abandoned long ago by NASA.
This simulation takes away the huge reward of the long travel time, and replaces it with a brief 30 day stint of freedom.
They'll surely get interesting results, they just won't be worth anything when it comes time to actually plan a real manned Mars mission.
bcg,
This looks really interesting, and using BitTorrent in tandem with a distributed computing queue scheduler (like XGrid, in the case of OMG) could provide not only the ability to effectively distribute coarse-grained tasks, but also efficiently share large input datasets for each process.
Thanks!
The comments so far have (mostly) overlooked the main point of just why the OpenMacGrid is different: it's *open*. That means that scientists, even PhD students like myself that want to run jobs using far greater numbers of nodes than the clusters (beowolf or otherwise) at our home institutions will now have a means to do so. Most such projects have neither the resources nor the capabilities to create their own custom cross-platform clients like those mentioned from other distributed computing projects.
OpenMacGrid (or just OMG, I guess) uses XGrid, which is built-in to every OSX 10.4 distribution and acts just like any other job queue manager, except it's even easier. So, the whole process of writing a distributed computing project becomes far simpler as well.
Finally, the OMG it doesn't matter if the OMG is cross-platform running on proprietary hardware: so is every other cluster that I as a scientist have ever had access to. The SGI cluster is proprietary, and to an extent so is the Linux machine at our High-Performance Computing lab on campus. And, if you're thinking about it being non-cross-platform from the client side, well, you're probably not thinking differently anyway, so just go download Folding@Home.
I don't know that China's space program is a sign of top-down economic planning, because largely the "communist" govenerment is no longer in control of the economy. They seem to be persuing a space program from the standpoint of national pride, perhaps exclusively. If you have a country of more than a billion people and can inspire them to work harder and be more loyal by building a few rockets, wouldn't you do it?
Unfortunately the US is not light-years ahead in biotech, especially stem-cell science. Any differences between our countries in science or technology will not last much longer, because they graduate so very many more scientists and engineers than we do. Granted, our colleges are the envy of the world, but increasingly foreign students are staying home and expending their genius there. This is why Tom Friedman and so many others are talking about how the world is now flattening even for knowledge workers, like scientists.
Actually, this little device could serve a purpose for me:
1) I live in an apartment small enough for the bluetooth signal to propogate easily throughout
2) I have no home telephone
3) I have occasional desire to speak at length with friends and family, but am somewhat limited by the expense of high-minute cell plans
4) Skype offers a call-forwarding plan that routes calls to other phones if unanswered on your computer
The net result is, for a small fee, I could have a "home" telephone number that anyone could call, and if I am within range of the bluetooth, it would ring my cellphone that way. But, if I'm not there, the call would be forwarded to my cellphone. Thus, with a single number, and a single phone, I would be reachable easily and probably much more cheaply than with a cellphone alone.
What Michael did was real reporting, believe it or not. He looked up the group that was sponsoring this conference and found that they were an industry-friendly group of scientists and "others" with a vested interest in seeding doubt of the Global Warming hypothesis.
/. editor for looking deeper than some corporate PR for a story.
Any tremendously complex system is hard to understand key aspects of, but the evidence I've seen (such as the plots of CO2 concentrations vs temperature), the systems modeling I've done, and the exhaustive global modeling done by hundreds of scientists around the world supports this key aspect of global warming: we are its cause.
As for everyone saying that money is holding GW scientists enthralled, don't you think that the oil companies (and US governemnt) would love to pay for studies disputing GW? There is not that much money in GW research; the total is probably somewhere in the few billions. The oil companies spend far more than that every year on finding new ways to pump more oil.
There is no serious scientific doubt that we are causing GW, and kudos to the
Equal weight would be given if the scientists who doubt global warming got to talk as much as those who see it in their science every day. If such equality were granted that BBC article would have given about two words to the "skeptics" conference, and the rest of the article would have been about real science.
Granting equality to fundamentally unequal propositions is ridiculous and counter-productive. The weight of evidence accumulated by serious, diligent scientists that demonstrates global warming is real would bury the doubting voices--almost always sponsored by interests opposed to environmental regulation.
As long as we are talking about spending taxpayer dollars, what is the social benefit repealing the estate tax? This will remove hundreds of billions from the nation's coffers, and could easily fund manned space exploration!
At least manned space exploration money funds jobs, pays for research and provides every American a source of pride. Other methods of squandering public funds like repealing the estate tax only serve to promote aristocracy, increase debt servicing costs (via increasing deficits), and widen the gulf between the richest and poorest in our country
Space is not some forum for inter-nation political posturing (which it was during the Cold War). If you
want to know why the US doesn't have an "unassailable" lead in the space race, it's because the space race
is over.
If China puts a man on the moon, then there's one more country that has the capabilities and know-how to launch
people into orbit. Now, we need to privatize that knowledge as well so corporations can get in on the game.
As soon as space launches become affordable (which would mean US$10/kg rather than US$1000/kg), then the world
can start using space for what it should be, additional space for the expansion of human life and enterprise.
Political posturing is a needless waste of taxpayers' money. Most people don't see the point in spending money
on the space program, so let corporations do it instead. They will do it better, more quickly, and, in the end,
more to everyone's benefit than NASA ever could.
Herein lies the biggest problem facing the environment and enviromentalists today. People
believe that solar, wind and hydroelectric power are "alternative" sources of energy. However,
these, along with geothermal energy are the only sources of energy available to our planet.
Fossil fuels were not deposited beneath the surface of the Earth like Uranium was. They were created
by life which is powered by the sun, wind, and geothermal heat. Fossil fuels took millions of years to be
produced and exist in only a limited supply and are found in currently very unstable regions of the world.
By burning these fuels we are doing the exact same thing that we would be doing by using Hydrogen in fuel cells.
We are releasing stored energy that was provided initially by "alternative" energy sources. So, in effect,
using hydrogen as a source of power for fuel cells would be the same thing as burning fossil fuels, but would
instead be more efficient, potentially more profitable, strategically advantageous (no middle east allies to worry about)
and would be indefinitely sustainable.
Apple is proprietary, true, but it provides products that users really enjoy to use, and is constantly innovating.
Just like most existing laser printers it could be configured to accept a huge variety of fonts provided by the publisher. The necessary fonts could even be included in the book's files.
standard copier paper is usually considerably worse...
Within a certain range, I am sure that the machine could be configured to use different weights and finishes.
don't forget the rest of the experience you would thus forgo...
On the contrary, bookstores would no longer have to stock multiple copies of individual books so they could have thousands and thousands of singly printed books available for the browsing! Think of how much of a bookstores shelfspace is dominated by 15-20 copies of the new Danielle Steel novel, etc.
Also, by using the machine overnight to print multiple copies of popular books, waiting times could be reduced dramatically. This machine seems to be an incredibly good idea, and I believe has very few drawbacks. It would enhance the typical browsing experience, cut costs to the publishers, enhance selection, allow greater access for new authors, and (presumably) save resources as well.