Actually, thinking about it, the pump at the bottom only has to provide a pressure differential big enough to stop the walls collapsing, and you put another pump at the top where its easier to service. You could probably do the bottom bit with an array of small motors with standard propellors on them. Put a few extra on to provide redundancy and make them robotically swappable/retrievable.
Also the reason you would have a pipe that big is that you definately want the flow rate to be low enough to maintain laminar flow. Turbulance would kill your efficiency.
Getting them to the surface would be easy, just attach a parachute and let them go in the tube.
Conservative assumptions:
1 Let's take your figure of 1% efficiency.
2 Assume equal amounts of warm/cold water, so deltaT = 7.5 deg.
Heat capacity of water is about 4.2 Joules/gm/degree
0.315 j/gm H2O
1 watt=3.17gm/sec
= 190 litres/min per KW.
You put the pump at the bottom, that way the pressure is slightly higher in the pipe than outside, and the walls are under tension , not compression. Its much easier to build that than a pipe that won't collapse under suction. Do it like that and 100m pipes are easy.
It's the energy cost. If you separate the colours it is much cheaper to re-smelt glass than to start from scratch with sand. The kicker is sorting the glass into colorless/green/amber.
That raises some interesting possiblities. If the reflections are directional then by using lasers in different locations you could display multiple ads while localising where they were visible from.
It would also lead to a whole new level of billboard hi-jacking - get your own laser and send a message to the world!
The downside is that such ISPs will have no ways to identify customers with infected Windows machines, disconnect them (or put them into some kind of "walled garden"), and tell the customers to clean up their PCs.
Why the hell not? This is something that they should either do in real-time or not at all. Why would you need six months or a years worth of logs to decide a machine was infected? If you can't tell within a few minutes then the infection is so mild it is the customer's problem, not the ISP.
The cost of de-orbiting material would come down a lot with industrialization of space. Cheap ablative heat shields and foamsteel wings and you can safely, cheaply and relatively gently land proverbial shitloads. Getting to space and building a manufacturing infrastructure is the expensive part.
It's only a 2.4% error at the kilo level. It compounds with each larger prefix, which is why it is now getting corrected.
kilo 2.40%
mega 4.86%
giga 7.37%
tera 9.95%
peta 12.59%
You've been reading too much fiction. There are no diamond asteroids, and even if there were, diamonds aren't worth much.
There are no radical new minerals out there either.
There are large amounts of various materials in the asteroids that could be useful, but it would take a lot of infrastructure lifted into orbit to even begin processing them. I think it is worth doing, and would eventually be profitable, but more through energy generation (SPS & microwave farm) and the removal of mining from earth than from directly selling exotic minerals.
The problem is with the scale of the rockets. Orion worked better with larger vehicle/payload combinations, up to thousands of tonnes of payload. Trying to launch that with chemical rockets would be difficult.
No. Done properly with relatively clean nukes and launched from mid pacific Orion would have had negligible radioactive residue, and would have launched massive quantities of hardware into space. Orion was killed by greenie FUD, not for any good reason.
Asbestos is nasty because of the shape of the particles. Its crystalline structure breaks down into tiny needles that are very difficult to cough up, and which just keep puncturing one cell after another.
Actually one of the main problems with hover technology is trying to turn corners. You can rotate the device about the Y-axis, but due to inertia it just keeps going in a straight line, only now you're going sideways. With the small hoverboards you could tilt them to introduce lateral forces in order to corner, but the amount of tilt needed isn't feasible for a full size car.
Actually one of the main reasons is the difficulty of building a reliable traction engine that can climb a circular column that tapers from a diameter of 100s of mm down to well below 1 mm. If you make it flat with a constant thickness, it is much easier to adjust for the changing width.
The way to look at cancer is not as a thing that is invading the body, but as a colony of things. They grow, divide, evolve and die. That is why it is generally fatal. The first chemo treatments will often kill >90% of cancer, but what survives is the cells that have mutated to be resistant. So the doctors prescribe a different chemo. Once again the susceptible cells die, but the colony goes on. There are basically only three ways you can permanently beat cancer: 1/ Sometimes you can cut it out - and get it all. 2/ Sometimes you can beat it down to the point where the immune system can beat it. 3/ Sometimes the cancerous mutation involves a weakness that makes a treatment 100% lethal to the cancer. But those are rare, mostly you are buying time not a cure. Back to the tangent, yes they are susceptible to replication errors, but in a colony those provide diversity for evolution to select from. That is one of the things that make cancer so nasty.
Slashdot Mirror
Well, I for one welcome our new dust mite overlords.
The middle of the deep oceans are practically lifeless. All the nutrients are along the coastlines and shallow seas and thats where all the life is.
Actually, thinking about it, the pump at the bottom only has to provide a pressure differential big enough to stop the walls collapsing, and you put another pump at the top where its easier to service. You could probably do the bottom bit with an array of small motors with standard propellors on them. Put a few extra on to provide redundancy and make them robotically swappable/retrievable.
Also the reason you would have a pipe that big is that you definately want the flow rate to be low enough to maintain laminar flow. Turbulance would kill your efficiency. Getting them to the surface would be easy, just attach a parachute and let them go in the tube.
Question: How many litres/min per KW
Conservative assumptions:
1 Let's take your figure of 1% efficiency.
2 Assume equal amounts of warm/cold water, so deltaT = 7.5 deg.
Heat capacity of water is about 4.2 Joules/gm/degree
0.315 j/gm H2O
1 watt=3.17gm/sec
= 190 litres/min per KW.
Seems pretty feasible to me.
You put the pump at the bottom, that way the pressure is slightly higher in the pipe than outside, and the walls are under tension , not compression. Its much easier to build that than a pipe that won't collapse under suction.
Do it like that and 100m pipes are easy.
It's the energy cost. If you separate the colours it is much cheaper to re-smelt glass than to start from scratch with sand. The kicker is sorting the glass into colorless/green/amber.
That raises some interesting possiblities. If the reflections are directional then by using lasers in different locations you could display multiple ads while localising where they were visible from.
It would also lead to a whole new level of billboard hi-jacking - get your own laser and send a message to the world!
The downside is that such ISPs will have no ways to identify customers with infected Windows machines, disconnect them (or put them into some kind of "walled garden"), and tell the customers to clean up their PCs.
Why the hell not? This is something that they should either do in real-time or not at all. Why would you need six months or a years worth of logs to decide a machine was infected? If you can't tell within a few minutes then the infection is so mild it is the customer's problem, not the ISP.
Once you take someones weapon away from them, you don't just merely use it against them, you beat the living shit out of them with it.
The cost of de-orbiting material would come down a lot with industrialization of space. Cheap ablative heat shields and foamsteel wings and you can safely, cheaply and relatively gently land proverbial shitloads.
Getting to space and building a manufacturing infrastructure is the expensive part.
It's only a 2.4% error at the kilo level. It compounds with each larger prefix, which is why it is now getting corrected.
kilo 2.40%
mega 4.86%
giga 7.37%
tera 9.95%
peta 12.59%
2.4% is tolerable, 12.6% is not.
You've been reading too much fiction. There are no diamond asteroids, and even if there were, diamonds aren't worth much.
There are no radical new minerals out there either.
There are large amounts of various materials in the asteroids that could be useful, but it would take a lot of infrastructure lifted into orbit to even begin processing them. I think it is worth doing, and would eventually be profitable, but more through energy generation (SPS & microwave farm) and the removal of mining from earth than from directly selling exotic minerals.
The problem is with the scale of the rockets. Orion worked better with larger vehicle/payload combinations, up to thousands of tonnes of payload. Trying to launch that with chemical rockets would be difficult.
No. Done properly with relatively clean nukes and launched from mid pacific Orion would have had negligible radioactive residue, and would have launched massive quantities of hardware into space. Orion was killed by greenie FUD, not for any good reason.
c - (epsilon)
:)
theoretically
Asbestos is nasty because of the shape of the particles. Its crystalline structure breaks down into tiny needles that are very difficult to cough up, and which just keep puncturing one cell after another.
Nah, it's a lot worse than being a galah.
If they hurt when you fall on them then the company that made them probably got sued into oblivion.
I have two axes, one of which I use to chop firewood.
No, when Microsoft creates a stable branch things will be equal.
Actually one of the main problems with hover technology is trying to turn corners. You can rotate the device about the Y-axis, but due to inertia it just keeps going in a straight line, only now you're going sideways. With the small hoverboards you could tilt them to introduce lateral forces in order to corner, but the amount of tilt needed isn't feasible for a full size car.
...and with the psychic group they don't even tell you where or when the meetup is.
Actually one of the main reasons is the difficulty of building a reliable traction engine that can climb a circular column that tapers from a diameter of 100s of mm down to well below 1 mm. If you make it flat with a constant thickness, it is much easier to adjust for the changing width.
The way to look at cancer is not as a thing that is invading the body, but as a colony of things. They grow, divide, evolve and die. That is why it is generally fatal. The first chemo treatments will often kill >90% of cancer, but what survives is the cells that have mutated to be resistant. So the doctors prescribe a different chemo. Once again the susceptible cells die, but the colony goes on.
There are basically only three ways you can permanently beat cancer:
1/ Sometimes you can cut it out - and get it all.
2/ Sometimes you can beat it down to the point where the immune system can beat it.
3/ Sometimes the cancerous mutation involves a weakness that makes a treatment 100% lethal to the cancer.
But those are rare, mostly you are buying time not a cure.
Back to the tangent, yes they are susceptible to replication errors, but in a colony those provide diversity for evolution to select from. That is one of the things that make cancer so nasty.
yes.