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On the contrary, see Meeting the Challenge: Training an Aging Population to Use Computers

Try your local public library. Most have taken up the challenge to get older adults on computers.

These techniques seem like brute force schemes to deal with the thermal resistance of chip packages -- you have to cool the heatsink to -110C in order to keep the "intel inside" at less than +60C). Why not use backside thinning. to bring the hot circuits of the processor within microns of a high coolant flux chamber. Backside thinning could get the coolant to within 10 microns of the junctions. If the CCD people can thin a massive 2k x 2k CCDs (the die is bigger than 1" square), I'm sure an enterprising overclocker could thin a Pentium.

Out in the Kuiper belt and the Oort cloud there are thought to be as many as one trillion objects - most small 1 to 10 km chucks of ice.

The really interesting question is, what is the mass distribution ? (I.e., how does the number of objects scale with their mass ?) This is basically unconstrained by real data. All such cosmic mass distributions are steep, but many (for example, planets in the Solar System, Asteroids in the Asteroid belt) are dominated by the most massive bodies.

If this holds true in the Oort cloud, in particular, there could be some pretty big objects. Even a Jupiter sized object might be able to hide from the Infrared surveys (the best way of detecting such an object).

I think ultimately the question is whether there is a single continuous "initial mass function" of isolated objects or not. The best idea as to how stars acquire their initial mass is that turbulence in the interstellar medium, which exists on all scales, establishes a power-law distribution of initial masses. Every once in a while, you get a very strong shock which passes by inside a giant molecular cloud and forces the collapse of a large region which then goes on to form a massive star. But more typically, you form stars more like our sun. And just as rare as massive collapses are very small mass ones which go on to form isolated brown dwarfs and free-floating planets. If this model holds up to be true, then we are all mincing words in our definitions of isolated systems, since they are all manifestations of the same universal formation process.

However, to avoid the difficult question of formation mechanisms, an IAU working group of some of the most respected people in the field established a working definition to define by fiat what it means to be a brown dwarf, and a planet. Extrasolar "planets" are those objects orbiting a star which are beneath the deteurium-burning limit -- regardless of how they are formed. "Brown dwarfs" are defined to be those which burn deuterium but not lithium, and "sub-brown dwarfs" (NOT free-floating planets!) are defined to be those isolated objects which do not burn deuterium. Even the working group itself admitted that this definition was not satisfying to a single member of the group, and so it is likely it will be replaced at a later time with something more physically-motivated. The "planet/planetismal/KBO" distinction was pushed back to our own solar system, since it will be some time before anyone sees anything that small in another system.

Also of interest is the following link, which gives a history of previous claims for additional planetary members of our solar system : SEDS.

Out in the Kuiper belt and the Oort cloud there are thought to be as many as one trillion objects - most small 1 to 10 km chucks of ice.

The really interesting question is, what is the mass distribution ? (I.e., how does the number of objects scale with their mass ?) This is basically unconstrained by real data. All such cosmic mass distributions are steep, but many (for example, planets in the Solar System, Asteroids in the Asteroid belt) are dominated by the most massive bodies.

If this holds true in the Oort cloud, in particular, there could be some pretty big objects. Even a Jupiter sized object might be able to hide from the Infrared surveys (the best way of detecting such an object).

I didn't word that well. Have they kept things quiet about potential disasters for one reason or another? You bet.

Okay, I'll bite. What do you have in mind?

You've obviously never bothered to look up the answers to that question yourself, because it took me one google search and a ctrl-f to find the answer - they were only exposed to the radiation for four hours each time, and they were protected by the spaceship.

This is exactly what I'm talking about.

Not exactly kosher to follow up to one's own posts, but...

Here's a PDF with the abstract for the Mars Ball. 1988 was the year in question.

Quoth the Reagan^Wposter:

Now, am I crooked? Or do I just think that whatever SCO's chances, some fool is going to come a long later and be willing to pay a lot more per share for this stock than I did, allowing me to sell it at a profit before the trial is over and walk away.

That's exactly what the market is betting on.

A lot of people feel that, win or lose, IBM will buy SCOX out. Either way, the stockholders get paid. That's why their stock hasn't tanked . . . yet. Now, when it becomes obvious that the game is up and SCOX will neither win nor be bought out, well . . .

Everybody, including Mel Gibson and his dog, know that God sent down an asteroid to earth, to clear the way for the creation of Man.

Think about it -- a sugar pill can help alleviate pain (and help heal a wide range of disease) with ZERO side effects. Isn't that the ultimate goal of any pharmacologist? This is an area of research we should all embrace, though it requires an open mind to do so. The mind has far more control over our body than medical science has been willing to admit.

More on Integrative Medicine

China tried same result in 1970s. Each small village and rural family had to produce X steel amount to meet national goal. Result was pathological disaster.

Don't mod the above off-topic, it's still about space! I submitted this story yesterday and it was rejected :( so here is probably the only place you're going to see it and it's really interesting imho! Cassini is entering the final phase of its 7 year journey to saturn and starting now will be sending back images and other measurements at a "rapid and steady pace". In a few months Cassini will enter orbit around Saturn after performing what should be a spectacular ring plane crossing.

Proof that there exist some functions with unobfuscatable properties (for some definition of unobfuscability) need not imply that practical obfuscation is not possible.

Christian Collberg has done some very interesting work on obfuscating programs at a high-level by densely intertwining their control flow and data accesses with a parallel heap-pointer-intensive computation. Sort of like a separate thread, with the key point that lots of dynamically allocated memory must be used to defeat analysis. This both obfuscates the original program and also helps in tamper-proofing (the original program can be modified by the compiler to rely on the values computed by this alternate thread).

Separating the main program from the inserted "thread" is much harder than checking and skipping some branch instructions in a decompiler or SoftICE. Static pointer analysis is an NP- hard problem for compilers, which makes de-obfuscation of this kind probably not practical.

Y.

Deimos and Phobos, while closer (23459 and 9378 km) to Mars than Luna is to Earth (about 384400 km), also have much smaller masses (1.8e15 and1.08e16 kg) than Luna (7.35e22 kg). [source]

Tidal forces (being a function of gravitational differential) are an inverse-cube function on distance, and linear with mass, so that would be a tidal force about 1/99th that of which we're used to. (Disclaimer: I am not a Physicist, but I share a house with one.)

While this is Mars, the concern isn't completely insane. If the rover's in position to get a 1% response from the Martian equivalent of the Bay of Fundy, we'll be needing yet another Mars probe, and someone at NASA should be needing a new job for putting it there.

What the Law Says:
The distribution of copyrighted materials over the Internet for which the distributor (any server - including your computer) does not have permission can be a violation of federal criminal law, a law called the Digital Millennium Copyright Act of 1998 (DMCA). Most of the music, games or videos downloaded through file-sharing programs like Morpheus or KaZaA lack permission of the copyright owner. And, those very programs that you use to download material, automatically open file-sharing services from your computer. So, without your knowing it explicitly, by downloading the program and the files your computer is programmed to share files back out into the international Internet community. You are therefore liable to be in violation of the DMCA, even if all you did was download a single song. Each criminal offense carries with it a minimum fine of $30,000 and a potential jail sentence.

Perhaps there are better ways to spend our research dollars now: http://medusa.as.arizona.edu/lbtwww/lbt.html

The main thing I'm thinking is that you need to be able to send lots of people at once. What's the crew capabilities on the Seawolf? I didn't check.

(I'm quoting this fact file.)

The Seawolf has a crew complement of 12 officers and 121 enlisted personnel for a total of 133 crew members. She's certainly no slouch. :-)

I suppose if we're just talking about a passenger shuttle craft, it doesn't have to be as big as all that in order to carry lots of people. The reason the shuttle has to carry so much 'dead weight' is because it has to support the crew for awhile when it gets up there, but if it could just go straight to orbit and dump its payload of passengers, it can probably be a bit smaller and still carry plenty of people.

Actually, a large portion of the shuttle's weight is allocated to its cargo. I've been in one of the shuttle mock ups and they have MASSIVE cargo bays (about the size of a school bus). According to one source they can carry up to 8,605 kg (18,970 pounds) of mass to the space station when the bay is pressurized. Assuming an average weight of 200 lbs. per person, plus another 3 tons for a special passenger module for the cargo bay, you could carry about 64 people per flight. Throw in a little extra weight for various incidentals and you could probably arrive at a reasonable figure of 50 passengers per flight.

The Seawolf is actually pretty small compared to a deep-space vehicle, I think, because of that one small thing. Sure, you could stick some ion drive units on there powered by the nuclear plant, but how fast would it go, then? How long would it take to accelerate? That's the real question. :)

Small? At 353x35x40 feet, she'd be plenty large for a space born vehicle. In comparison, a two bedroom camper with kitchen and toliet is 40 feet long and about the width of a conversion van. Since a peaceful space vehicle wouldn't need so many crew (no battlestations), it would be as good as a luxury liner.

As for thrust, the Prometheus for the JIMO mission thrusts about 1 newton per second (one kilogram of acceleration per second) on a 10 megawatt reactor. According to the navy's specs the PWR/S6W reactor on the Seawolf can put out 220 megawatts of power. Assuming a linear increase in power, that would give our fictional Spacewolf a thrust of 22 Newtons.

Of course, I doubt that the military would be happy with 22 newtons of thrust. They'd probably want a more powerful fission drive. Options include NERVA, GCNR (Gas Core Nuclear), Nuclear Salt Water, and Orion drives. All of those have a very high thrust in exchange for a lower Isp than Ion drives. However, their Isp is still significantly higher than today's chemical rockets, and yet they can produce comperable thrust.

I'm curious enough about this that I'd be interested in seeing a breakdown of how much each component and system of the Seawolf-class sub weighs. I don't want anything classified, of course, but if someone can give this information I'd really be interested in seeing it.

I seriously doubt you'd get anywhere near those specs. However, if you strip out the weapons, the ballast tanks, the screws, the reactor rotors, the sonar and reduce the crew, you'll probably be able to save yourself a good fraction of the weight. Space versions of some of the above would have to be installed in orbit, but you're probably still saving yourself a bundle.

Of course, all of this is just facts and figures. None of this means that launching a Seawolf into orbit is a good idea, bu

It appears that there is actually very few areas on Mars that aren't at least some what rich in H20. Frozen or not, we can melt it, Nuclear reactors are good at too:) The map shows that only a few spots here and there are red(have no H20). Most of the Planet is at least green (there are medium levels of H20) and the rest of it is blue or purple which means that its saturated with the stuff. Not that the finding by ESA was pointless.It is indeed great news and its always good to confirm our data.I just figured I'd point this out because I don't know about the rest of the slashdot crew, but it sure excites me that people (maybe me too) might be living on Mars in my lifetime.
Regards,
Steve

If one thinks of quantum computing as a kind of parallelism, then maybe so.

More specifically, Wein's Law.

AU: Astronomical Unit, defined as the radius of the Earth's orbit, appprox 93M miles. Used for convenience and because when you get such large values that change all the time, people get sloppy. :)

Mars' orbit is ~1.6 AU from the sun. (See Bode's Law.) This means that Mars can be as little as 0.6 AU's or as much as 2.6 AU's depending on where the planets are in their orbits relative to one another. Communication times therefore would range from about 4-5 mins to 20+, one-way.

The spacecraft are relatively slow to travel, since they coast the whole way. The path they take is a long leisurely curve so that less rocket fuel is required. There's a good animation of the path at Nasa (MPG, MOV.) So the timing of the launches is chosen for when the locations of Mars and Earth give the easiest launch (least energy required) and communications is secondary.

Hope this helps.

The short time I knew Gene Shoemaker
- famous now for his comet and asteroid impact discoveries and theories,
you could tell his early dreams of being the first scientist to the moon were still a motivation
- helping others reach out to space...bringing space closer.
A health problem prevented him from completing his lunar assignment during Apollo.
He did run the geology program for the missions.
And Gene eventually made it to the moon - posthumously.
- the only human whose remains are partly *buried* on another world... so far.

Putting telescopes on mountaintops solves a quarter to a third of that problem, since a good hunk of the atmosphere is below you . Adaptive Optics solves another big hunk of the problem. And until we can fabricate the space telescope in space it will be possible to build earth based telescopes much larger for much less money.

I think you will find that it will be easier to grind a spherical primary mirror rather than a parabolic one. Look here for implementation instructions. there will neet to be a resulting adjustment to the secondary optics to compensate for the difference in shape. but the grinding process will be much simpler.

I'm talking about the fact that there are several ground-based observatories that consist of multiple telescopes (Keck, Magellan, VLT, LBT), and that one of the goals of this design is interferometry. None of these telescopes is currently planning on doing optical interferometry, because it's just too hard. They're all working on infrared interferometry, and even that is very difficult to accomplish. Especially with mirrors mounted independently, as all except the LBT are.

I just saw that the U of A is offereing a course for Objective-C/Cocoa. Unfortunately you have to be in the CS major to take it. Not much listed about the course, but here it is in all its.... glory?

emacs in action

Anybody who has ever gone beyond darkroom 101 knows that the best photographers do some of their best work with subtle manipulations in the dark room. Adams' zone system is all about remapping the intensities in the original scene onto a pleasing span of whites to blacks in the print. Adams himself said that "Dodging and burning are steps to take care of mistakes God made in establishing tonal relationships." Digital cameras and image manipulation programs only pickup where the relatively crude processes in the darkroom leave off.

Anyone who claims that photography is about objectively and accurately portraying the real scene knows very little about the nonlinear properties of human vision, film, and image reproduction systems and they know even less about art.

Not unless the generally accepted definition of spam is changed. Currently, spam is considered to be the inappropriate attempt to use a mailing list, or USENET or other networked communications facility as if it was a broadcast medium by sending the same message to a large number of people who didn't ask for it. Mass junk E-mail. -University of Arizona Library

Since telemarketing is a one-to-one call, it probably wouldn't be covered without some sort of alterations to existing laws.

When scientists look for life out side the solar system, why don't they focus on moons of Jupiter like planets instead of finding Earth like planets.

Actually, they have looked for moons around extrasolar planets that eclipse their star. The main example (so far) of the "transiting technique" is HD 209458b, a hot Jupiter in a 3-day period. This transit has been observed using Hubble, with a sensitivity that would allow one to detect Saturn-like rings or moons as small as twice the size of Earth. None were found. More information here.

Of course, a 3-day period planet's moon would still be unable to harbor life as we know it (too hot). But these are the first steps being taken to look for such objects. As more transiting planets are detected, this technique will tell us a lot about moon systems around these planets.

Moons of giant planets in temperate zones may indeed be the key to finding life-sustaining bodies. Our own Moon stabilizes the rotational axis of the Earth, which prevents many extreme climatic changes. Compare this to Mars, which has no large moons (only two small ones) that lead to the same stability. A giant planet would have a similar affect on the dynamics. This is just one example of how a second body (in our case, the Moon) aids the development of life. One can ponder how much the probability of life drops off if such a body does not exist, though I'm not sure anyone has a convincing answer, yet.

We can barely image planets that are twice the size of Jupiter and you are suggesting we should image MOONS!?

So far, scientists have been unable to image any extra-solar planets at all. The planets have been detected indirectly--by looking at the effects of the planet on the star. An overview of these techniques. Astronomers have directly imaged brown dwarfs, which are somewhat like both planets and stars. We can't yet image exoplanets, but we can still learn a lot about them.

Direct imaging of planets may be made with the Keck Interferometer in Nulling Mode (a similar setup is being designed for the LBTI in Arizona, and the European VLTI), or with "Extreme Adaptive Optics", or finally with the Terrestrial Planet Finder.

It is even possible to quantify that processing power to something not beyond reach of current computing technology given some assumptions about how exactly [the] brain operates.

there not a piece of single experimental data in the literature that suggests the universe is not computable because minds do funny things.

Penrose tends to the belief there are some non-computational processes that in the universe and they may underly consciousness.

"With apparently genuine humility, Penrose emphasizes that these ideas should not be called theories yet: be prefers the word 'suggestions.'"

there is no uncomputable component in the system

I don't put much faith in AI, either.

I think I left my brains floating in this VAX.

All thats needed are the Navier-stokes equations, for the wind, and the heat equation for the temperature. Predicting the rain is rather simple given the temperature and pressure everywhere. The only problem is due to chaos, so inaccurate measurements will give very bad predictions. No geology is required, All thats needed is 19th century physics.

- Better Earthquake, volcano and other natural disaster prediction

This article states:

At present, we can determine which areas of the Earth have the most potential for damage, but we cannot determine within a short time when a major earthquake will occur. We know from historical records and observation how often many faults move, thus we can tell which are due to move next. However, we can only guess with an accuracy of +/- 50 to 150 years; not very useful for evacuating towns before a quake. Narrowing the window of earthquake occurence to a few hours or days would be extremely useful, but at the same time is the hardest part of earthquake prediction.

It doesn't sound terribly useful to me.

More accurate mapping

If you are talking about GPS, that was from the space program, not geologists. The techniques used before were millenia old.

Geology has saved millions of lives, billions of dollars and created millions of jobs.

The advances you list have not saved millions of lives, and probably not billions of dollars either. If any come close why didn't you list them?

Creating jobs does not mean its useful. If people were paid to sit around and do nothing, would that be useful? We could have full employment, while still having people starving, with nothing produced.

On one hand you have a model including a 14 billion year old universe, and on the other you have a 6000 year old Earth...

Well, here's some very basic data for you, you stupid piece of shit.

Or, instead of getting some clue, maybe you should just DIE ! YEAH YOU HEARD ME BITCH, I WISH YOU'D BE FUCKIN' DEAD !

Maybe not. But, I have an idea of how good it should be, and we're not there. Don't take offense if it seems to me that you have no idea how bad we have it from just a few short years ago.

Until you've seen the face of a person terrified at the idea of meeting any police, or a person shaking after getting a ticket, or a person afraid to talk to anyone in government, then you should talk.

I can guess by your lack of experience that you're without a permanent tan and haven't been pulled out of line by airport security for having one. Not through any fault of yours, as we are all birthed in our skin by chance. I would submit that freedom isn't a state of being, but a continuous struggle against those who hypocritically only value their own rights while disregarding yours. Freedom isn't very anything. It simply is or isn't happening. It can start or it can stop. The freedom to access a lawyer when your arrest has been categorized as a "terrorist action" has stopped.

We are free. We are very free. You can walk up to the White House and picket it. You can drive your truck with a rifle in the back. You can say what you want on the Internet. You can read the books you want.

Anyone can do any of the things you've mentioned and more. It is simply a matter of the consequences that becomes the deterence to those activities. Even expressing yourself on the internet can be a dangerous proposition. To keep this reply short and educational, I'll simply point you to a source you can learn from.

Even if another terrorist attack occurs, do you think they're going to take these liberties away? No. The government won't. In fact, they can't. Because people like myself speak up and let people like you know what is going on.

You're statement has a naivete that is almost charming. On the other hand, it is also a sad indictment of our public schools' failure to teach history in any meaningful manner. This failure is one the reasons why historical events repeat themselves in such tight, short cycles in the U.S., which is reflected so heavily in our foreign policies.

Our founding fathers knew what they were doing a hell of a lot better than you give them credit for.

I give them all the credit. Many of them are my heroes. Unfortunately, they are dead. The dead cannot defend their dreams. Its up to you and me to defend them at home, so that bad things don't happen to other people.

= 9J =

Do you mean a Dyson Sphere? link Actually, scientists have been planning since 1991 to blow up the moon, so maybe the sun is just the next step.

The original poster made a comment about never getting to play with watermarking code. Along with some informative papers about software watermarking, obfuscation, tamperproofing, etc and uses for such techniques, there is an implementation on the SandMark website.

The paper cited in the first link is from a professor I once had.

On his website I found his full article, if you want some details about watermarking techniques. It's has a lot more meat than presentation slides.

This sounds like The Garbage Project

Penrose is no idiot, but when he says that he is out of his area of knowledege and way out of his depth.

The Titan Probe does indeed have cameras. It will take images all the way down once it passes the cloud deck and it even has the capability for rudimentary color images. Titan's beaches are in fact, just what we may see.

The Titan Probe does indeed have cameras. It will take images all the way down once it passes the cloud deck and it even has the capability for rudimentary color images. Titan's beaches are in fact, just what we may see.

Planet X is an proposed tenth planet with an orbital period of less than 1000 years. When Pluto was discovered, astronomers thought that was the planet that was responsible for Uranus' orbital perterbation. Then in the 70's and 80's Uranus' orbit didn't quite sync with predictions that accounted for Pluto. The discrepancy suggested that there may be yet another object lurking in the Kuiper belt.

In any event, the the two hypothesis are addressing different issues. A good write up can be found here.

I assume (based on this article) that we've been watching the skies for 100 years, and that this has been the closest pass in that time. That means that any give year we have a 1 in 25,000,000 chance of an impact.

Based on this simple history it's apparent that there have been 2 impacts of similarly sized asteroids in the past 500 years. Either A) my impact probability is off by 5 orders of magnitude or B) this has been a quiet century for near-misses. That kind of statistical variation is unlikely, so what's wrong with my numbers?

Assuming that we've only been able to accurately record near-misses for 20 years drops my probability of impact to 1 in 5 million. Based on that answer there should have been 1/10000th of an impact in the past 500 years. My answer is still off by 4 orders of magnitude. Assuming independent asteroids of 1m volume I go down to 1 order of magnitude error.

I'm going to keep thinking about it, but I have to do a problem set now. I'm interested if anyone sees a flaw in my logic or math, or simply has comments.

High [sic] Definition Porn
YES!
oh, and Star Trek will look nice as well.

There are 2 unusual lessons from the development of digital video. The first lesson is that pornography is the driver of improvements in video equipment -- from VCRs to HDTVs. Adult video is something that you simply must see -- with the eyes. If the resolution improves by 50%, then the porn video becomes 50% better. Adult video is a multibillion industry if you measure all the videos produced in the world.

The second lesson is that there is simply no justification, whatsoever, for allowing H-1B workers to work in the United States of America (USA). Allow me to explain.

We are all familiar with the comparison between the UltraSPARC III and the SPARC64-V. The management of Sun Microsystems says that it absolutely must have H-1B employees in order to build the "best" microprocessor, the UltraSPARC III. By comparision, Fujitsu hires almost exclusively native employees (i. e. Japanese citizens) and used native employees (not foreign workers) to build the SPARC64-V. It implements the same insruction set that the UltraSPARC III implements but significantly outperforms the UltraSPARC III on 3 key benchmarks: SPECint2000, SPECfp2000, and TPC-C. Please verify the performance characteristics of the SPARC64-V at the web site for SPEC and the web site for TPC-C.

Another interesting example is high-definition television (HDTV) Please read "The History and Politics of DTV".

The typical foreigner claims that H-1B workers help to give American companies a technological edge to create whole new industries. The typical foreigner claims that foreign workers helped the Americans to leapfrog the Japanese in the area of HDTV. The Japanese had established an HDTV standard prior to 1989 and had begun broadcasting HDTV programs by 1989, but this standard was based on analog techniques. In the 1990s, the Americans developed an HDTV standard based on digital techniques. The foreigners claim that foreign brainpower helped the USA to leap ahead of Japan.

Not really. Once the HDTV standard based on digital techniques was established, the Japanese (and the Koreans) commercialized the technology. Most of the HDTV products that you see in the USA are manufactured in Japan (and Korea).

The lesson here is that, "even if" terminating H-1B employment may diminish American innovation and simultaneously increase innovation in India (for example), the Indians may not be able to effectively commercialize the technology. Given the superiority (e.g., low rate of software piracy) of Western society, the Americans would be able to out-commerialze any innovation that appears in India before the Indians achieve commercialization.

The phrase "even if" is used because there is simply no evidence to suggest that terminating H-1B employement will diminish American innovation. Innovation is a hard thing to predict -- for the very reason that creativity is hard to predict. For example, Japan was initially ahead in HDTV by using analog techniques in the 1980s; at the time, many "experts" predicted that the USA would fall permanently behind in HDTV technology. Nonetheless, the USA raced ahead in HDTV by using digital techniques. Now, Japan is ahead again by pushing the envelope of HDTV technology to create ultra HDTV.

... from the desk of the reporter

But of course it must be smaller than a planet.

Really?

Pluto is smaller than seven of the solar system's moon according to here( Moon, Io, Europa, Ganymede, Callisto, Titan and Triton) and its a planet.

Wow that's an ugly place to pick for a vacation:
phobos