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Here's a question: as the earth's magnetic field is based significantly on the location of the magnetic pole, the strength of any electromagnetic field varies significantly depending on the incidence angle of incoming particles (ie to exclude solar wind) has anyone studied what impact this shift would have on earth's climate?

Looking at http://wdc.kugi.kyoto-u.ac.jp/... the pole has shifted 5x the distance recently as at the start of the last century. Does the northward shift of the magnetic field by 16-17 degrees with increasing speed track at all with increasing surface temps?

While I make a living with technology I still love old mechanical things and look back at how they were made and used. It's fascinating to see clockwork mechanisms with gears that had teeth that were hand-filed and laid out using a compass. The typewriter was a product of the industrial revolution and the complexity and the nuances of some of those design decisions, like the QWERTY keyboard we all know and love were products of that era.

It's sad when we lose a living link to that kind slide rule and french curve technology. Mr. Whitlock was probably so adept at what he did that he could identify a problem just from the description. I can also imagine a back room where there are boxes and boxes of spare parts gathering dust, just waiting for a broken Smith Corona or Olivetti to come through the door.

Sure, it's faster and easier now with modern technology but we all need to remember that technology and progress builds upon the prior innovations and in 20 years I'm sure people will probably laugh and these bulky tablets and cell phones we all cling to much like Smegle and his precious ring. I learned to type on typewriters, old clunky things that could jam your fingers and rip paper just by looking at it. I also remember the story of the neighbor's cat getting it's tail caught in the carriage. They wound up cutting it's tail off because they couldn't get it freed. Ahh the halcyon days of correcting fluid and carbon paper, a bygone era now replaced by MS Word.

As I tell my kids, when we lose a piece of our history we lose a little of ourselves.

This gamma ray camera from the same institute may be something related? It seems to use Scintilation from a dislocated electron (which gives away path and energy) combined with the point of impact of the gamma ray on a detector plate.

Actual web site of promoter. Even worse car-related web site of promoter. He's been plugging this since 2009 or so.

Laser-induced fission is quite feasible, and requires far less energy input than laser-induced fusion. Laser fission of thorium has been done on a small scale as a lab experiment. Thorium reactors have been built, with modest success.

A pure thorium reactor won't achieve criticality, because thorium has no isotopes that fission on their own. The fuel has to have uranium or plutonium mixed in to start the nuclear reaction. The laser concept seems to be to use a laser to get things going.

There's been some interest in accelerator-pumped thorium fission. It's been tried in Japan, but that group hasn't reached breakeven. It's a plausible concept, but so far nobody has been able to figure out a way to make it work.

Incidentally, this is not a "clean" process. It generates radioactive by-products where the accelerator beam hits the thorium, in addition to the usual nuclear reactor fission products. A car-sized version is a fantasy.

• Free tuition
• Monthly living stipend
• Japanese technology (my Master's right now is in music + robots)

Since I began here 1.5 years ago, they started ANOTHER program called "Global 30", which means they're recruiting 300,000 foreigners for research, Master's, and PhD's from now till 2020. All over Japan. Here's an example of the program from Kyoto University. http://www.opir.kyoto-u.ac.jp/kuprofile/e/courses/index.html There are lots of programs in different fields, at different universities (Waseda, Tokyo University, Osaka University), so just browse around for what you like.

No the rotational axis is along the North Geomagnetic Pole not the Magnetic North Pole. You've obviously confused the two.

Kids are taught to navigate via Polaris but it is not an exact measure of North.

• LablGTK. GTK on Windows. Yuck.
• LablTk. Tk is a toy GUI kit.
• OCaml-Win32. If you have to ask what's wrong with the win32 API, you've never had to use it in a language other than C.
• Some alpha or out of date binding of wxWidgets or Qt for OCaml.

OCaml programs aren't shorter than scripting languages, and they're limited to a curses interface at best. Together with its speed, OCaml gives off the impression of being a language you'd reach for when you write high performance, low interaction programs---like automated financial trading agents. Not many of us do that. And so not many of us use OCaml.

Why would they hire a physicist who dabbles in earthquake detection when they've got seismologists who do this full-time around, who know that radon levels are not an accurate predictor of earthquakes?

Because the many many seismologists who are paid to do their jobs obviously did not.

The earthquake science community looked at it and dismissed it decades ago as insufficiently reliable--some earthquakes aren't preceded by a spike in radon levels, and some spikes aren't followed by an earthquake,/quote> ...yeah, right, because all, these reports are obviously written by sci-fi writers

Have YOU even thought about what you are blabbering?

Well... lets not dignify your question with a response, shall we?

Well, there are also official repositories from skype
deb http://download.skype.com/linux/repos/debian/ stable non-free
Google
deb http://dl.google.com/linux/deb/ stable non-free
And Canon printer drivers
deb http://mambo.kuhp.kyoto-u.ac.jp/~takushi/debian ./

FYI, here's the video library.

Look closely at two comparable tests:

• Clip5 Limited-hold memory task (Human, 5 numerals, 210 mses)
• Clip6 Limited-hold memory task (Ayumu, 5 numerals, 210 mses)

There's a BIG difference in the testing: the human gets no cookies! <grin>

But seriously, I have to admit it is an intriguing test. What I would love to see, though, is another set of test runs which compared chimps with some serious gamers!

FYI, here's the video library.

Look closely at two comparable tests:

• Clip5 Limited-hold memory task (Human, 5 numerals, 210 mses)
• Clip6 Limited-hold memory task (Ayumu, 5 numerals, 210 mses)

There's a BIG difference in the testing: the human gets no cookies! <grin>

But seriously, I have to admit it is an intriguing test. What I would love to see, though, is another set of test runs which compared chimps with some serious gamers!

FYI, here's the video library.

Look closely at two comparable tests:

• Clip5 Limited-hold memory task (Human, 5 numerals, 210 mses)
• Clip6 Limited-hold memory task (Ayumu, 5 numerals, 210 mses)

There's a BIG difference in the testing: the human gets no cookies! <grin>

But seriously, I have to admit it is an intriguing test. What I would love to see, though, is another set of test runs which compared chimps with some serious gamers!

Commercial fusor devices can generate on the order of 109 neutrons per second ...
whos not reading the links?

And Bussard's claim:

These four definitive tests showed true Polywell potential well trapping of ions at ca. 10 kV well depth (with a 12.5 kV drive), with total DD fusion neutron output of ca. 2E5 nts over a period of about 0.4 msec; giving an average fusion rate of about 1E9 fus/sec - over 100,000 times higher than the results achieved by Farnsworth/Hirsch for DD at such low energies, and 100x higher than their best with DD even at 150 kV (Ref. 3)


If you can buy a commercial fusor with 1E9 neutrons/sec driven at 12,5kV then please provide a link to it. Otherwise it's irrelevant as we are talking about "at comparable drive conditions".


Where is the math? The charge density in the core can't be significantly far from equilibrium.

That does not mean one can assume that the charge distribution is uniform.

If his math is correct we would get much larger yields from the pure fusor devices.

Have you been following research on multiple potential well formation then? Yoshikawa has some very interesting simulation and experimental results. He goes as far as noting:

The results strongly suggest that the high neutron production rate should be attributed to not only the well depth but also the unstable behaviour of the potential, i.e. the intermittent peaking of the density in the centre region. A numerical simulation reveals that IEC possesses a favourable dependence of fusion reactions on the injected ion current for the application to a neutron source or a fusion reactor.

  He's not alone in looking at the effects of multiple potential well formation on fusor efficiency either. People at Illinois University, University of Wisconsin, and LANL are all quite interested.


The biggest loss in high energy plasmas is from Bremmstrahlung radiation from electrons, the ions thermalize via ion-electron collisions. Even Bussard claim that. Non equilibrium systems make it worse by having low energy electrons, and this pushes the probability of colliding with one up...
Oh I don't have my calculations handy, but i could dig them out. They are not publishable because its been published more than once or twice.


And what ion and electron density and velocity distributions would you have used? Calculating Bremms for a plasma with oscillating density distributions is quite device specific. All the harder when virtual cathode and anodes come into play. You can't just average it out and then say good enough. You most certainly can't go dismissing experimental results on such a basis. Even if the experimental results are just for a 0.4msec pulse, that's interesting enough results to maybe see how the confirmation test goes. Thankfully it's been funded so we should get some experimental data to work out what the density and velocity distributions might look like in a year or so.

The dumb shit has obviously never heard of Riemannian geometry or the fucking Riemann metric tensor

einstein was awarded the nobel prize for his brownian paper. relativity, published the same year, was all but ignored.

source:
http://www.bun.kyoto-u.ac.jp/~suchii/einsteinBM.ht ml

The challenge is to rip those oxygen atoms from the silicon and calcium atoms. This is hard because they are tightly bound. Moreover, I doubt NASA would be interested in any process that consumes some other non-moon-available chemical (trading 5 lbs oxygen for 10 lbs of a reducing agent). I suspect that some sort of electrolysis might do the trick, but even that might be outside the power budget.

I see nothing wrong in your C++ version, while your ocaml version clearly sucks: you are memoizing using a complex key, and an association list, meaning that accessing memoized information costs a lot.

If you are concerned by performance, you should use a complete cache, like in your C version.
FYI, I uploaded an ocaml translation of your C code. It doesn't use mutable state except for memoizing, and uses pattern-matching on lists, and recursion rather than for loops, but otherwise it follows closely your code. Performance should be very similar.

http://wwwfun.kurims.kyoto-u.ac.jp/~garrigue/garde n2.ml

Ah, btw heres a link to a model airplane project that flew using microwave-transmitted power

If you have a mech that's approaching 20 ft tall, then you can have a cockpit that allows a full range of motion for the pilot in a full-body haptic feedback harness. (See this site for a full-arm haptic harness.) Short of a direct neural interface, this is the only way you're going to provide force-feedback. If you don't have force-feedback, then you won't be able to control a bipedal humaniform robot well enough to do real combat.

But if you dispense with dynamic balance, then you can build mecha on tracks like these Japanese guys did for real! T-52

For one thing, you seem pretty unclear about what my other points are. (That the control technology already exists to do this, and that it's decades old. And that this guy doesn't seem to appreciate the control problems.)

You're putting words into my mouth. No one's damning him. But his project is not going to produce anything that looks like *combat* unless there's some pretty sophisticated dynamic balancing capability.

Imagine that mecha A and mecha B are fighting. A is not dynamically balanced and has no haptic feedback from its limbs, but B is dynamically balanced by a human pilot getting feedback through a full-body haptic interface. B grabs mecha A's arm and gives a good tug. If mecha A was a human being, then it would sense the amount of force exerted through its arm, then shift its feet or stumble to keep its center of gravity over its feet -- perhaps even slacken its arm to prevent the transmission of the impulse. But since mecha A has no dynamic balance, it can do none of this. If mecha B pulls hard enough, then mecha A's left foot might even be levered entirely off the ground, and the pilot would have no immediate feedback.

Contrast this to what happens when you grab a human's arm a give a tug. If you stop and think about it, dozens of things all happen at once as a reflex to keep you from falling over. A mecha with haptic feedback can leverage this naturally evolved ability. Maybe the monster truck crowd is going to be impressed because of all the heavy metal, and the clashing of big clubs on steel, but the perceptive ones will notice that combat without balancing capability look like a couple of toddlers duking it out.

Without balancing tech on the level of Asimo, I'd rather put my money on a non-bipedal robot like the
T-52

Maybe rather than having go back and forth continuously for fuel it'd be more economical in the long run to build a reactor on the moon and have energy transmitted back to Earth via microwaves. Something like this http://www.kurasc.kyoto-u.ac.jp/plasma-group/sps/y amasaki-e.html

I use O'Caml for about two years now, and I like it immensely. I also know Perl. When I compare the two, I'd say the problem with O'Caml for scripting is that it's more cumbersome to write regular expression matches in O'Caml than in Perl. And I have to say being able to write regular expression matching easily really is the key to many scripting tasks that I'm aware of (not necessarily what I do).

There is a remedy though. O'Caml comes with camlp4, a Pre-Processor-Pretty-Printer, which basically lets you customize the syntax of your program and add syntactic sugar. I imagine a variant of O'Caml language based on camlp4 that puts regular expression matching in syntactic sugar will make it very suitable for scripting.

In fact, I itch over this idea badly that I might do it. If I have the time. ;-)

For the issue of libraries, O'Caml actually has an OpenGL binding before PHP does! Haha.

When a core melt-down happens, there is not a damn thing on this planet (that I know of) that can the molten (and getting hotter by the second) glob that used to be the core.

It has been theorized that if this happens, the molten core will burn through the earth until it reaches water.

part(s) of the core of Chernobyl 4 melted down. (though i'm not entirely sure if this was due to a runaway reaction producing too much heat, or due to external heating from the graphite moderator fire started by the steam explosion. nor am i sure which would be the worse thing.)

what basically happened was that the molten core material had to melt its way through its containment (what there was of it). in the process, of course, it became diluted with molten whatever-it-had-just-touched matter. this can't go on forever without the core matter going subcritical; the "china syndrome", melt-through-the-planet scenario presupposes some mechanism for the fissile material to stay homogenous and concentrated, and i for one can't think of any.

I vividly recall a physics professor of mine, about 25 years ago, who worked on fusion, saying: "It will be almost impossible. The neutron flux for efficient, continous power generation is so intense that no known materials could sustain the exposure". He talked about materials getting brittle- the materials in closest contact with the fusion core would fail (in weeks, months) and there was no cost effective way to deal with that for long term, stable, low-cost power generation.

Well, if you look at the topics of a conference (11th International Conference on Fusion Reactor Materials) in Japan just a few weeks ago, that problem has not gone away yet.

Every microwave I've ever taken apart just has the series of control parts (timer, switches, fuse) and the magnetron\waveguide assembly part of which is a feedhorn pointed directly into the cooking cavity.That's all it is. The metal chassis of the microwave reflects or grounds out the RF. The problem is not only does a microwave operate very,very close to the 2.5 gig band just like 802.11 spec it also has a crummy "see thru" screen on the front with holes punched out just slightly smaller than 1 or 2 mm. Just small enought to keep wavelengths around 10-12 centimeters and below inside the box and anything above that escapes. The magnetron is noisy, it emmits spurious rf across the spectrum. The FDA has emission standards for the later model ovens. 5 mWatt/sq.CM at any point within 10 CM of cooker! Most new microwaves do a lot better than that. Solution: obviously make better sheilding inside the box, maybe a wire webbing. (I wonder what's up with pacemakers?)

Mining itself does not make sense as a first step. The first step is power generation. We need to place a few microwave transmitting solar power stations into orbit first. Then we could use some of that energy to drive lasers that would push materials into space at a low cost. Then we could use those technologies and materials to build bases to mine from.

The benefits of this sort of progression is that when the power satellites are not being used to push spacecraft they can be used to generate almost 100% clean energy with no chemical pollutants, particulates, radioactive waste, damming of rivers, or CO2 emissions. The power stations would pay for themselves quickly and would actually have the space program generating revenue rather than just being a cost.

This site also has some interesting information on beamed-power research.

There are even competitions!

This site also has some interesting information on beamed-power research.

There is a discussion about this on Lambda the Ultimate.

These links don't require registration :-)

According to the West Legal Dictionary, in the US, US law generally views monopolies as harmful and points out that generally speaking - monopolies are illegal.

There are only a few times when monopolies are granted, two of those times are when Patents and Copyrights are granted (which is why the big fight in the Supreme Court was so important and why it was so very important for the Supreme Court judges to knock down the extensions Congress put into place). Other times are when someone owns the rights to a single thing (like an oil well), or holds the patent on a process (like making Apple Computers).

Abusing your monopolistic power is not only illegal, but it is sometimes very hard to prove. So there you are right. However, Apple has abused their monopoly in the past. It is just that they got burned several times in court battles and since then they have become more sensitive to acting in non-monopolistic ways. Not that this won't change in the future but at least for now they are acting quite decently for a monopolistic company.

I'd vote for Jobs. He's not my #1 pick, but I think he might be better than what we have already. Not that GWB is horrible or anything but his grim determination to invade Iraq no matter what just doesn't sit right with me. It is like he has lost focus of the fact the UN guys are not finding any kind of a smoking gun (and yeah I know - they hid them. But with all of the technology we have shouldn't we be able to track down where everything is located? I mean, look at how well satellites can see underground rivers. If we can see that why can't they just locate suspicious underground areas? They used satellites to locate cities also. So what's the deal?

(I know - off topic. Sorry - got into a rant.)

Rogue is an ancestor of sorts to Net Hack, hence the term "rogue-like games"

More information, including a timeline, can be found here.

This is a really interesting opportunity for some high-tech to be applied to a real non-military situation. Robin Murphy came here to UCSD and talked a few months ago, and she actually brought (and we got to drive) the tracked one with the flippers in front.

Those things are not easy to drive. One of the most difficult things is getting a perspective on where the robot is in relation to it's surroundings (very rough rubble). This is an ongoing research area for many robotics teams, and one we have been working on also.

The submitter mentioned something about autonomous robots, I think they don't fully understand the difficulty of the problem which robotics researchers are working on. Navigating uneven building wreckage autonomously is an incredibly difficult problem, in general. Especially under the conditions of the WTC rubble. There may be some small parts of the process which can be automated, but I doubt it would be useful in this situation anyway. They were using the robots as probes to discover what was inside areas where it was dangerous for people to be there, so a human is already "in the loop". The real use of these systems is for remote visualization (i.e. show me what's in there) in hard to reach areas.

They didn't specify what types of cameras are being used, but this is a mostly visual problem from my understanding. Most robots have standard rectilinear camera views that are forward facing, unfortunately operation of these platforms is difficult becuause of the restricted field of view and inability to see on the left, right and behind the robot. Multiple cameras helps, but adds significant complexity and disjoint views. A technology which really makes this easier is an Omni-directional Video sensor (which has a 360 deg. field of view around the sensor). These are ideal for "immersed" applications like this, and they literally give the operator a view of the entire space around the bot (except for directly overhead) and allow you to determine the robot's orientation relative to obstacles easily. The same data can also be unwarped and used to create a perspective or panoramic view of the area in real time. A pair of these and stereo software (which also has been done in our lab, [shameless plug over]) can provide a full depth-map of the area. The ODVS has the difficulty of limited resolution (same CCD, larger fov) but this can be supplemented by a Pan/Tilt/Zoom rectilinear camera.

Really the interesting part of research in this direction is the remote operation and visualizations that help the perator navigate through the area to achieve it's goal. This is what my thesis is on, actually.

More info: UCSD CVRR Lab The Page of Omnidirectional Vision and our source of ODVS. Also check Vstone (in Japanese, may need to run that last one through babelfish or something).

Mobile Robots are cool. We even have one that pulls cables for us in the drop-ceiling of our lab... we're slowly working on a web-page for that new one.. I have a cool video for it already but it's HUGE (100M or so). Anyway, I'll shut up.

The Korteweg-de Vries (KdV) equation is a good example

u_{xxx} + 6uu_x + u_t = 0

which describes very similar types of waves (albeit in one dimension). A selection of the solutions can be found here.

I guess that the reason for the quoted "devastating effects" is that solitons are comparatively stable waveforms, which are much less prone to dissipation and dispersion than smaller waves which remain within the regime where the real equations of motion of the water are close enough to the linear wave equation. Soliton waves can travel long distances in relatively unchanged form (and hence still carry all of their initial energy when they finally do hit the coastline).

One of the first recorded experimental observations of a soliton was a bow wave of a boat that John Scott Russell followed for several miles on horseback before losing it in the twists and turns of the canal somewhere near Edinburgh, Scotland. IIRC solitary waves under these conditions do behave somewhat like the KdV solutions.

Cheers, Mark
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