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Comment: We gotta get NASA to stop smoking crack.... (Score 1) 170

by rgbatduke (#48620231) Attached to: NASA Study Proposes Airships, Cloud Cities For Venus Exploration

and then writing science fiction. I don't even disbelieve what they say, it's just being said without any sort of consideration of either the cost or the benefit. Hey, I can write novels about mining the asteroid belt, extracting He3 from moon rock for fusion fuel, building orbital space cities, and settling the moon too, except that Heinlein and many others already did most of this, and all of their novels presuppose some method of getting around that doesn't cost a gazillion dollars and thousands of megajoules per kilogram moved. With that kind of cost, why hire crack smokers to write SF? There is a lot of work a lot closer to home that is ALREADY too expensive for the benefit.

In the meantime, time to write another SF novel: "The Floating Cities of Venus". Yeah, got a nice ring to it.

rgb

Comment: Re: Why does this need a sequel? (Score 1) 294

by Samantha Wright (#48593013) Attached to: Blade Runner 2 Script Done, Harrison Ford Says "the Best Ever"

...Not having any particular stake in this argument, are we quite sure that's Tyrell's intended meaning, something so mundane? I think Tyrell is more taking about stuff like this:

I have seen things you people wouldn't believe Attack ships on fire off the shoulder of Orion. I watched c-beams glitter in the dark near the Tannhauser Gate. All those moments will be lost in time, like [small cough] tears in rain. Time to die

...i.e., Roy's greatness and accomplishment as a person. At that point, Tyrell wants to sooth Roy and make him accept his place by calling him amazing. Simply saying "well, that's the cost of bein' so darn strong" conflicts with his next line: "And you have burned so very, very brightly, Roy."

Comment: Re:Efficiency??? (Score 1) 103

by rgbatduke (#48521813) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

You're probably right. Although I've had a standard transmission car go through 100% of its clutch plate and they are not cheap to replace. But what is? And how many cars have standard transmissions any more? And of those, how many go through a whole clutch plate before they die from some other cause. Toyota's magnetic regenerative braking system suggests that one "can" mass produce the requisite magnetic coupling, but there probably isn't a compelling reason to do it in this case.

Comment: Re:Efficiency??? (Score 4, Insightful) 103

by rgbatduke (#48513715) Attached to: Practical Magnetic Levitating Transmission Gear System Loses Its Teeth

The other point being that it could be designed only to replace the kinetic friction parts of a transmission, the parts that synchronize the system. The gearing itself can probably still be mechanical. Not having to replace clutch plates, for example, might be a nice and relatively easily doable thing.

Comment: Re:Sigh. Or rather Sci...Fi (Score 1) 153

by rgbatduke (#48456905) Attached to: NASA Offering Contracts To Encourage Asteroid Mining

Precisely! In fact, I'm thinking of rewriting Plato's Republic except replacing all instances of Philosophers with Science Fiction Writers. Think of the advantages! Instead of neurosing over healthcare and global warming we can have replacement organs, dinosaurs and space aliens! We can build our own space habitat! The Stars are Ours! No longer will mankind be limited by silly little things like physical law and economics, not with SF writers in control.

Best of all, SF writers tend to be pretty nerdy and (if we carefully exclude the horror contingent and zombie squad) inclined towards epic-heroic monumental happy endings. Life could never be boring with them in charge.

On to the asteroids! Don't worry about cost or whether or not the risks are worth the benefits! Damn the space torpedos! So what if another million or two of small children die of easily preventable causes this year! It helps reduce the rate of population growth, and how can that be a bad thing?

rgb

Comment: Sigh. Or rather Sci...Fi (Score 3, Informative) 153

by rgbatduke (#48450311) Attached to: NASA Offering Contracts To Encourage Asteroid Mining

Science fiction authors have totally solved this problem a zillion different ways. They all share certain features. First you go to the asteroid. Second, you set up some sort of mass driver on the asteroid or ion driver, ideally one that uses solar electricity or heat and not imported fuel, but if you don't mind a bit of radioactivity, propulsion by nuke is OK (Orion).

Depends on the mass of the asteroid as well, and how long you want to wait to get it home, and how much of it you want to have left when you get there. If you don't mind waiting a VERY long time, you could even use an angled light sail for propulsion. Third, you drive it home, or rather, have your fully automated computer tools do it for you. Fourth, you get it into Earth Orbit and then use it to threaten the hegemony running Earth, insisting that they send you dancing girls and exotic foods or you'll drop it on their heads -- it makes you way more money than actually selling the metal.

Optionally, you can have your robots smelt the asteroid in place first, using large mirrors to concentrate solar energy to melt the asteroid rock into slag plus metal, perhaps even collecting the slag (with a thin metal coating) to use in your linear accelerator or solar heated rocket as reaction mass. Some asteroids are really comet heads and might be covered with solid gases and ice and might support making real fuel on the spot as well. And fusion would no doubt shift the plan a bit as well.

But the final stage is always to drop them on Earth, not use them for good. Otherwise there isn't any real plot. Sometimes they don't even bother dropping them per se, they just fall by accident. But nobody can resist an umpty teraton-of-TNT explosion: not invading space aliens, not Dr. Evil, not the asteroid mining company's board of directors, not even the grizzled old asteroid miner whose sainted mother was put out onto the street to starve during the housing riots of 2057.

rgb

Robotics

Robots Put To Work On E-Waste 39

Posted by Soulskill
from the robots-disassembling-robots dept.
aesoteric writes: Australian researchers have programmed industrial robots to tackle the vast array of e-waste thrown out every year. The research shows robots can learn and memorize how various electronic products — such as LCD screens — are designed, enabling those products to be disassembled for recycling faster and faster. The end goal is less than five minutes to dismantle a product.

Comment: Re:Fucking magnets, how do they work? (Score 3, Informative) 26

You mean, as in "read a physics textbook"?

Seriously. Depending on how much physics you've already studied, the right place to start will vary. A passable (free) intro is in my free online physics textbook http://www.phy.duke.edu/~rgb/C..., or wikipedia articles. A good intermediate treatment might be Griffiths' Classical Electrodynamics. If you want the pure quill uncut stuff, J. D. Jackson's Classical Electrodynamics is excellent, but it is not for the faint of heart or the wussy of PDE-fu.

In a nutshell, parallel currents of electric charge attract; antiparallel charged currents repel, changing charged currents radiate electromagnetic energy, and there are electrostatic forces happening in there somewhere too, in the cases where the currents are produced by unbalanced moving charge. Oh, and there is a fair bit of twistiness to the magnetic fields (called "curl") and forces, and the currents in question in "magnets" (or the general magnetic susceptibility of materials) tend to be non-dissipative (quantum) nuclear, atomic, or molecular circulations of charge, not Ohm's law type currents in a resistor. Ferromagnets in particular are what is being referred to, and they are characterized by long range order and a "permanent" magnetization in the absence of an external field below a certain temperature.

Hope this fucking helps:-)

rgb

Comment: Re:Not exactly (Score 3, Interesting) 161

by rgbatduke (#48322563) Attached to: New Particle Collider Is One Foot Long

Besides, the invention of accelerators order of 12" in size is very, very old news. The Betatron:

http://physics.illinois.edu/hi...

is, as one can see, order of a foot in diameter and could produce electrons at order of 6 MeV in 1940. Yes, that is actually before the US entered WWII and long before the invention of the cyclotron. That is gamma ~12, or v ~ 0.997 c. So if the top presentation were at all relevant to TFA it would actually be boring. One might safely conclude that it is wrong and boring.

The betatron was damn near the first particle accelerator truly worthy of the name, and was just about exactly 12" in diameter (a bit larger than that including the frame for the magnets etc) as one can clearly see in the second photo on this page if not the first.

rgb

Comment: Re: How about we hackers? (Score 4, Insightful) 863

Yeah, I've done a fair bit of time as sysadmin of several networks AND enjoy the cool stuff that comes with change and improvement in hardware and software over time.

Systemd no doubt will have growing pains associated with it, but I still remember the "growing pains" associated with kernel 2.0 (the first multiprocessor kernel) and issues with resource locking and ever so much more. Anybody want to assert that this wasn't worth it, that "single core/single processor systems were good enough for my granddad, so they are good enough for me"? Server environment or not?

Decisions like this are always about cost/benefit, risk, long term ROI. And the risks are highly exaggerated. I'm pretty certain that one will be able to squeeze system down to a slowly varying or unvarying configuration that is very conservative and stable as a rock, even with systemd. I -- mostly -- managed it with kernels that "could" decide to deadlock on some resource, and when the few mission critical exceptions to this appeared, they were aggressively resolved on the kernel lists and rapidly appeared in the community. The main thing is the locking down of the server configurations to avoid the higher risk stuff, and aggressive pursuit of problems that arise anyway, which is really no different than with init, or with Microsoft, or with Apple, or with BSD, or...

But look at the far-side benefits! Never having to give up a favorite app as long as some stable version of it once existed? That is awesome. Dynamical provisioning, possibly even across completely different operating systems? The death of the virtual machine as a standalone, resource-wasteful appliance? Sure, there may well be a world of pain between here and there, although I doubt it -- humans will almost certainly keep the pain within "tolerable" thresholds as the idea is developed, just as they did with all of the other major advances in all of the other major releases of all of the major operating systems. Change is pain, but changes that "wreck everything" are actually rare. That's what alpha/beta/early implementation are for, and we know how to use them to confine this level of pain to a select group of hacker masochists who thrive on it.

On that day, maybe just maybe, systemd will save their ass, keep them from having to replace some treasured piece of software and still be able to run on the latest hardware with up to date kernels and so on.

I've been doing Unix (with init) for a very long time at this point. I have multiple books on the Unix architecture and how to use systems commands to write fully complex software, and have written a fair pile of software using this interface. It had the advantage of simplicity and scalability. It had the disadvantage of simplicity and scalability, as the systems it runs on grew ever more complex.

Everybody is worried about "too much complexity", but Unix in general and linux in particular long, long ago passed the threshold of "insanely complex". Linux (collectively) is arguably one of the most complex things ever build by the human species. The real question is whether the integrated intelligence of the linux community is up to the task of taming the idea of systemd to where it is a benefit, not a cost, to where it enables (eventually) the transparent execution of any binary from any system on a systemd-based system, with fully automated provisioning of the libraries as needed in real time as long as they are not encumbered legally and are available securely from the net.

We deal with that now, of course, and it is so bloody complex and limiting that it totally sucks. People are constantly forced to choose between upgrading the OS/release/whatever and losing a favorite app or (shudder) figuring out how to rebuild it, in place, on the new release -- if that is even possible.

I'll suffer a bit -- differently, of course -- now in the mere hope that in five years I can run "anything" on whatever system I happen to be using and have it -- just work.

rgb

Comment: Why bother... (Score 1) 272

by rgbatduke (#48250697) Attached to: A Library For Survival Knowledge

a) It's already done, and is called "wikipedia". The problem of accessing wikipedia after the solar flare in a few days wipes out human technological civilization is left as an exercise for the reader.

b) OK, so it's not really done, and is going to be even less done as paper books more or less disappear from the world and people stop learning how to read because their personal digital implant delivers content directly into your cortex in full sensory mode, all of which goes away when a nuclear war followed by a space alien invasion reduces humans to a marginal species living in abandoned mines and sewage tunnels and living on rats. Brevity is then the soul of wit. We need three things:

1) How to make and blow glass.
2) How to turn glass into lenses and lenses into microscopes and telescopes.

These two things are already sufficient. They extend human senses into the microscopic and macroscopic, otherwise hidden, Universe, and nothing but common sense and observation is required from that point on. However,

3) How to build a printing press.

is also good, provided that people can still read.

Oh, you want to rebuild civilization QUICKLY? Either we're restarting from a partial, not full, reboot (that is, we still have easy access to things like unburned oil and coal, iron, maybe a few undamaged nuclear power plants with the engineers to run them) or it's just not happening!

The problem, you see, is easy access to those resources. The more we deplete the Earth's crust of readily minable resources, the harder it is to reboot civilization on a collapse. We just don't have a lot of places where oil still comes oozing up to the surface of the Earth, for example, so why and how exactly are people going to go looking for it a kilometer or two down? How easy is it going to be to find any? Steel requires iron (still fairly plentiful, granted) and coal. Hmmm, easy coal isn't so easy any more. Easy copper, not so much. Easy aluminum? No such thing, needs massive amounts of electricity (although ore is still plentiful enough. Even making chemical reagents like sulphuric or nitric or hydrochloric acid (key to building nearly anything interesting) require sulphur, salt, electricity.

This is what is going to be tough. Bootstrapping directly from type 0 pre-civilization to type 2 civilization is going to be very difficult if we've depleted all of the easy pathways to 2 while we are type 1, even if we preserve usable copies of wikipedia, the CRC handbook, the library of congress science section, the entire proceedings of the IEEE, and a complete copy of all patents ever filed in the US patent office (and have people who can read them, and who have managed to learn calculus and build stuff). Hydroelectric power, maybe. Alcohol can drive simple motors. But going straight to nuclear or photovoltaics is going to be pretty much impossible, and going the coal/oil route we've followed the first time is going to be much, much harder.

The best thing, therefore, is to take care of the civilization we've got...

rgb

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