I suggest you look at a teardown of the Cube. It was pretty much had a regular-looking PC board in a somewhat novel case. The Cube also made severe performance compromises to run fanless.
A lifetime, let us note here, is a very long time for us.
So this discussion is about the definition of a "long time"? I think 50 years is not that long to establish a completely new industry in a completely new place. How long did colonization of the New World take? And that was on Earth, with people already living there. Give it time.
And what else? That's not much to show for half a century of activity.
It's not like it has been 50 years with no commercial exploitation. Most launches now are commercial. There are several space tourism companies now chugging along. There is a private enterprise trying to mine an asteroid. There are more and cheaper space launch companies springing up. Just because you consider 50 years to be a long time does not mean we should give up.
My point is that a designer considering concrete would have allow for the possibility that the concrete might get mixed wrong and not last 1000 years. With stone this would not be a concern.
And that's if someone even wanted a concrete structure that lasted 1000 years. The stuff is ugly IMHO.
We have vastly superior quarrying and transportation technology compared to the Romans (or Egyptians). If you were interesting in building something that would last 1000 years, you would probably choose stone over non-reinforced concrete, if not for aesthetics then because you would have trouble guaranteeing the mix.
Remember that there is some selection bias going on here. The Roman concrete that didn't last 1000 years is long gone.
That works great for new development when there is a local monopoly. My area, like most of the older Philadelphia suburbs, was initially developed by the railroad companies. They made very little money on passenger service, but made boatloads selling real estate around newly installed commuter rail.
I don't think they would have bothered if they didn't own a large swath of land around the rail line, though. That would just make a competing developer rich.
How can you say that when there are hundreds (thousands?) of commercial satellites floating around? When we have private companies starting to engage in space tourism? "Half a century" is not even a single lifetime. My dad can remember Sputnik, to say nothing of my grandfather, who had fought a World War by then. Many (most?) of the bridges you drive over are from the same era, depending on where you live.
Seriously, I bring my daughter into the men's room because she is too young to use the restroom herself. I think we are putting too much weight on this stuff. A gay man can get his jollies in a men's room, or a gay woman can hang out in the ladies' room, I suppose, but in practice it isn't a real problem.
I'm not going to flame you because I came at this from the same direction. I discovered that I was wrong. You are correct that transgendered people have a mental-physical mismatch, and you can certainly describe this as a mental problem and be accurate, if perhaps insensitive.
That said, there is no treatment available that works better than sexual reassignment surgery. I feel that the minor adjustments that we need to make to accommodate these people pale in comparison to what we do to accommodate people with physical handicaps, and we should probably help them if we want to see ourselves as compassionate. If a person who is obviously a dude wants to behave as a lady, the least I can do is go along with the ruse if it means they are more likely to be happy and less likely to commit suicide.
Like any condition, if an option someday arises that works as well or better than surgery, they should definitely pursue that - but in the meantime, just have some compassion for someone with a very difficult life.
I'm betting that using random volcanic ash is probably just as risky as hunks of granite or marble.
I'm typing this on a marble countertop in my kitchen that is probably pumping me full of radiation, but then I worked out in the sun all day and I KNOW I got a lot of radiation:)
I'm not sure that steel rebar would care much, but the lime makes concrete so alkaline that glass fiber breaks down - so there might be an opportunity to go with composite rebar. On the other hand, I'm betting that even with "only" 10% lime, it is still really alkaline. The pictures from the news release linked in TFA show a lot of lime.
I completely agree that this will turn into a big pork fest. That said, I feel that it's worth it because it will eventually boot-strap the private sector.
The value of the material in the asteroids is only high when compared with the cost of launching the same materials to orbit. Private industry won't go after asteroids unless someone is building big stuff in space. You can't build big stuff in space affordably without materials. Chicken and egg.
If the ingredients are more expensive, the cement will be more expensive. For instance, the Roman variety calls for more aluminum and less sand. They also mention unspecified "minerals" as being present in Roman cement that are not normally present in Portland cement.
I'm not pooh-poohing their efforts, I'm just skeptical that lime-ash concrete as used by the Romans will lead to breakthroughs. I think their work is very interesting, and any kind of discovery like this lets us better-understand our world. It's just that if you make concrete much more expensive, other materials start to make more sense. For instance, if I'm making a big breakwater, eventually a giant hunk of stone will be more economical than concrete. The scientists involved seem to be chasing the carbon angle, since the Roman lime was baked at a lower temperature and yet they still made decent concrete. If we could learn to do that, that would indeed be nice...
I'm pretty sure the Roman concrete is still very porous - especially given the way they say it cures by water creeping in and activating the reaction. Here is the press release, which has much better detail than TFA.
I hear ya, but if I'm an artist that is going to build a 5000-year building, I'll go with big blocks of attractive stone. This stuff would likely be super-pricey.
It won't be worth patenting, if they even found anything new recipe-wise. Most concrete is steel-reinforced, and most of the failure you see is the rebar corroding. It's not hard to imagine how a lime-volcanic ash mixture would make this unsuitable for steel-reinforced concrete.
Slashdot Mirror
I suggest you look at a teardown of the Cube. It was pretty much had a regular-looking PC board in a somewhat novel case. The Cube also made severe performance compromises to run fanless.
Guns don't kill people, toddlers kill people.
You should start a White House Petition to fund your magic rock. Mine has permanent magic that keeps the Earth from flying off into space.
4 by terrorists on US soil.
The programs are working!
A lifetime, let us note here, is a very long time for us.
So this discussion is about the definition of a "long time"? I think 50 years is not that long to establish a completely new industry in a completely new place. How long did colonization of the New World take? And that was on Earth, with people already living there. Give it time.
And what else? That's not much to show for half a century of activity.
It's not like it has been 50 years with no commercial exploitation. Most launches now are commercial. There are several space tourism companies now chugging along. There is a private enterprise trying to mine an asteroid. There are more and cheaper space launch companies springing up. Just because you consider 50 years to be a long time does not mean we should give up.
My point is that a designer considering concrete would have allow for the possibility that the concrete might get mixed wrong and not last 1000 years. With stone this would not be a concern.
And that's if someone even wanted a concrete structure that lasted 1000 years. The stuff is ugly IMHO.
We have vastly superior quarrying and transportation technology compared to the Romans (or Egyptians). If you were interesting in building something that would last 1000 years, you would probably choose stone over non-reinforced concrete, if not for aesthetics then because you would have trouble guaranteeing the mix.
Remember that there is some selection bias going on here. The Roman concrete that didn't last 1000 years is long gone.
That works great for new development when there is a local monopoly. My area, like most of the older Philadelphia suburbs, was initially developed by the railroad companies. They made very little money on passenger service, but made boatloads selling real estate around newly installed commuter rail.
I don't think they would have bothered if they didn't own a large swath of land around the rail line, though. That would just make a competing developer rich.
How can you say that when there are hundreds (thousands?) of commercial satellites floating around? When we have private companies starting to engage in space tourism? "Half a century" is not even a single lifetime. My dad can remember Sputnik, to say nothing of my grandfather, who had fought a World War by then. Many (most?) of the bridges you drive over are from the same era, depending on where you live.
I'm open to suggestions. It certainly is nasty in there.
Gah... concrete roads. I'm from NJ originally, you are giving me flashbacks! Bu-bump-bu-bump-bu-bump-bu-bump...
She's not staring, she's squinting ;p
Wow, that must cause hell at the restrooms... :)
Seriously, I bring my daughter into the men's room because she is too young to use the restroom herself. I think we are putting too much weight on this stuff. A gay man can get his jollies in a men's room, or a gay woman can hang out in the ladies' room, I suppose, but in practice it isn't a real problem.
I'm not going to flame you because I came at this from the same direction. I discovered that I was wrong. You are correct that transgendered people have a mental-physical mismatch, and you can certainly describe this as a mental problem and be accurate, if perhaps insensitive.
That said, there is no treatment available that works better than sexual reassignment surgery. I feel that the minor adjustments that we need to make to accommodate these people pale in comparison to what we do to accommodate people with physical handicaps, and we should probably help them if we want to see ourselves as compassionate. If a person who is obviously a dude wants to behave as a lady, the least I can do is go along with the ruse if it means they are more likely to be happy and less likely to commit suicide.
Like any condition, if an option someday arises that works as well or better than surgery, they should definitely pursue that - but in the meantime, just have some compassion for someone with a very difficult life.
I'm betting that using random volcanic ash is probably just as risky as hunks of granite or marble.
I'm typing this on a marble countertop in my kitchen that is probably pumping me full of radiation, but then I worked out in the sun all day and I KNOW I got a lot of radiation :)
Non-reinforced structures can also be made out of things like huge blocks of solid rock, which tend to also last a long, long time :)
I'm not sure that steel rebar would care much, but the lime makes concrete so alkaline that glass fiber breaks down - so there might be an opportunity to go with composite rebar. On the other hand, I'm betting that even with "only" 10% lime, it is still really alkaline. The pictures from the news release linked in TFA show a lot of lime.
LOL, I'm presuming it's some bound form of Al. :)
I completely agree that this will turn into a big pork fest. That said, I feel that it's worth it because it will eventually boot-strap the private sector.
The value of the material in the asteroids is only high when compared with the cost of launching the same materials to orbit. Private industry won't go after asteroids unless someone is building big stuff in space. You can't build big stuff in space affordably without materials. Chicken and egg.
If the ingredients are more expensive, the cement will be more expensive. For instance, the Roman variety calls for more aluminum and less sand. They also mention unspecified "minerals" as being present in Roman cement that are not normally present in Portland cement.
I'm not pooh-poohing their efforts, I'm just skeptical that lime-ash concrete as used by the Romans will lead to breakthroughs. I think their work is very interesting, and any kind of discovery like this lets us better-understand our world. It's just that if you make concrete much more expensive, other materials start to make more sense. For instance, if I'm making a big breakwater, eventually a giant hunk of stone will be more economical than concrete. The scientists involved seem to be chasing the carbon angle, since the Roman lime was baked at a lower temperature and yet they still made decent concrete. If we could learn to do that, that would indeed be nice...
I'm pretty sure the Roman concrete is still very porous - especially given the way they say it cures by water creeping in and activating the reaction. Here is the press release, which has much better detail than TFA.
I hear ya, but if I'm an artist that is going to build a 5000-year building, I'll go with big blocks of attractive stone. This stuff would likely be super-pricey.
It won't be worth patenting, if they even found anything new recipe-wise. Most concrete is steel-reinforced, and most of the failure you see is the rebar corroding. It's not hard to imagine how a lime-volcanic ash mixture would make this unsuitable for steel-reinforced concrete.
I didn't feel that I needed to say that, it is so blatantly obvious. These numbers all only work if you are already paying for internet.