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  1. Re:Stereolithography machine hype on Open-Source 3D Printer Lets Users Make Anything · · Score: 1

    It's not a mass-production technology. However, these devices (or more likely, the fourth- or fith- generation removed of these devices) could well be a wonderful personal-production technology.

    Consider: need a new pair of shoes? Load a design into the house-hold replicator, push the button, come back later and pick it up. Or more likely (as an intermediate stage, if nothing else), go to the shoe store, select a design from the variety available (having previewed in-store display models), adapt with measurements from your feet, push the button, and come back a little later and pick it up. Or watch as it's made "before your eyes".

    This is starting to roll out in specialised areas. For example - go to the music store, buy your tracks and have it burnt on the spot (bad example, I know). Or to a book store, buy a book and get it printed and bound for you. It's got lots of advantages for retailers, mainly in that they need less storage space (equates to less rent), and they don't have unsold inventory that they need to shift at sale price or return.

    Prior to the Industrial revolution, most things were either made locally, or very expensive specialist items, or not available. Personal manufacturing systems will result in a shift back to this model, with an even greater focus on intellectual property rights.

  2. Re:Might be just a scam! on Scientist Are Working to 'Steer' Hurricanes · · Score: 1

    The purpose of the thought experiment was merely to show that the energy levels required aren't out of reach - even if ten or hundred times as much was needed, it would still be achievable (though even more impractical).

    However, as a practical level, I think this would be a bad idea - the cyclone exists because of an energy imbalance (too much heat in the water), and is very efficient at correcting that imbalance. Case in point: when Cyclone Larry hit northern Queensland, Australia, in 2005, it cooled the local Pacific ocean enough to give the Great Barrier Reef a couple of more years of life (it's dying due to warming ocean waters). Breaking up or steering a cyclone will mean that the energy imbalance doesn't get corrected - so you just get another one, possibly a bigger one.

    If we want to avoid big cyclones, we should look into ways of correcting that imbalance earlier, with less devastating effects.

  3. Re:Might be just a scam! on Scientist Are Working to 'Steer' Hurricanes · · Score: 1

    Yes, but that's my exact point - the huge natural energies provided by the Earth's environment (including the Sun) can be manipulated by relatively small amounts of energy - of the level that humans can manipulate and control.

    It's actually the global warming debate in microcosm - yes, humans can change the environment.

  4. Re:Might be just a scam! on Scientist Are Working to 'Steer' Hurricanes · · Score: 1

    A one degree Celsius temperature difference, over an area of a few hundred square kilometres, would steer a hurricance. We know that humans can generate many times this difference - the thermal plume of any city is considerable larger.

    It takes one calorie of energy to heat one gram of water by one degree C. One gram of water is one millilitre of water, or one cubic centimetre (approximately). A square meter of surface area, to one centimetre of depth, is 10000 cubic centimetres - 10 kilograms of water.

    There are one million square meters to a square kilometre, so every square kilometre is 100,000 tonnes of water (to one centimetre depth). It takes a million calories to heat a tonne, so it's going to take 100 billion calories to heat a square kilometre of water.

    One calorie = 4.184 joules. So we need 418.4 gigajoules of energy to heat. 1 joule/second = 1 watt. So we need 418.4 gigawatts to heat that water in one second, or 418.4 kilowatts to heat that water in 1 million seconds (11.5 days). More practically, it's 6.97 megawatts to heat it over the course of one hour, or a bit less than 500KW to do it in a day. So we need, to heat a hundred square kilometres of ocean, in a day, about 50 MW. (As we're using solar, it will actually take about two days)

    You can buy, commercially, 1KW solar panel arrays, which take up about 3mx3m - they're about $10,000 each. You need 50,000 of them - $500,000,000 if you don't get bulk lots (yeah right), and they'll take up approximately a square 670 meters across. They're only about 5-10 cm thick, so you get lots of them in a relatively small volume for transport, though assembly will be a pain - I'd look at automating it if possible.

    In short, there is nothing about these numbers that make it impossible - impractical, probably, but far from impossible.

  5. Re:Might be just a scam! on Scientist Are Working to 'Steer' Hurricanes · · Score: 4, Informative

    Not really.

    Cyclones have insane energy levels, true, but they are still storms and winds, and they obey natural laws. One of these laws says that they drift based on pressure differentials in the surrounding area - ie, if the air pressure is higher to the north than the south, the cyclone will head south.

    Air pressure is related to temperature; hot air rises, which will make the air pressure go down, while cold air sinks, making the air pressure go up (*warning: highly simplified explanation!*).

    Besides, this technique is what already causes cyclones to break up - when they hit land, the temperature grade becomes very uneven, because land absorbs heat differently to water. This creates an asymmetrical bulge or dip in the cyclone - which is bad for what is basically a rotating disk of air. This asymmetry forces the cyclone to rip itself apart - usually by sending storm systems deep inland. Nor does it take a huge difference to do this - cyclones are chaotic, unstable systems: science speak for saying that a small push can send it into a different state.

    For an easy analogy - imagine a motor biker rider. The motor bike, going at 100MPH, has insane amounts of kinetic energy, compared to what the rider could normally attain. But the bike is an unstable system - a small nudge of energy (rider shifting balance, for example) can make the bike change direction. Of course, get this wrong, and disaster strikes - too much energy causes the bike to fall over.

  6. Re:Been there, done that on The New Moon Race · · Score: 1

    Not to mention that even if there are no mineral resources on the Moon (unlikely; it's made out of material peeled from the Earth's mantle, which is where we get all our mineral resources today), then it's still a great place for a base to go and intercept asteroids from. And we know that there's tons of resources in asteroids.

    Yeah, the Chinese will probably do it dirtier than the US would, and they'd spend lives to do it. Blood is the standard currency for these sort of endeavours - look at the lives lost building, say, the first East-West railroads in the US. Or the Panama canal. The Chinese have the technology to do it, the political will to do it, and see value out of doing it. So it's no surprise that they will do it.

  7. Re:What did Debian do for the US DST change? on Debian Refuses To Push Timezone Update For NZ DST · · Score: 1

    Except that the tzdata2006p-1 package was released to stable on Nov 28 - a couple of weeks _after_ the previous release. So it didn't make the release, but they put it into stable anyway. From the 2006 news archive, the 3.1 update occurred Nov 6, with the next one going out in Feb. This set a precedent - timezone data was worth backporting.

  8. Re:What did Debian do for the US DST change? on Debian Refuses To Push Timezone Update For NZ DST · · Score: 3, Insightful

    Ah... found it (and in a link from the FA, as well... go figure). The US DST changes, according to this bug report went into tzdata2006p - which, sure enough, got the changelog got pushed to stable Nov 28.

    So that does beg the question - if it's okay to do it for the US, why not NZ?

  9. What did Debian do for the US DST change? on Debian Refuses To Push Timezone Update For NZ DST · · Score: 1

    Near as I can tell, the US DST change went into tzdata2007d - so it's not in the one in stable either (unless I got the timeline wrong).

    So - what did Debian do for that? If they left it in volatile, then the NZ guys haven't got anything to complain about, really - at least the Debian folks are consistent (in this scenario)

  10. Re:After a minute and a half on Google. on Space Rope Trick Experiment Goes Awry · · Score: 1

    Except that the temperature ratings for the material are in an atmosphere - not a vacuum. Thus, the two points aren't related.

  11. Re:After a minute and a half on Google. on Space Rope Trick Experiment Goes Awry · · Score: 2, Informative

    Not really, because temperature in space doesn't work the way you seem to think it does.

    If it's -20C on Earth, a human will lose heat fast. Why? Because the heat will transfer from the person to the surrounding air via conduction.

    In space, there's no air (duh). That means you don't lose heat from conduction - only via radiating. Furthermore, if this experiment was done in sunlight (probably), then rather than losing heat energy, the line would almost certainly have been gaining it.

  12. Re:Heh on The Pirate Bay Files Suit Against Big Media · · Score: 2, Insightful

    1) They're already off the street - they're in jail. Killing them doesn't take them off the streets any better. (Assumption - if they weren't getting the death sentence, they'd have life without parole)

    2) I personally don't go for the religious argument, I admit - just thought I'd throw it in there.

    3) High security prisons can still make money, you know.

    4) You always have rights. Prisoners have some of their rights suspended, not all of them. Go re-read your constitution.

    5) Problems with the law also apply to the penalty - the penalty is part of the law after all

    6) I pointed out that death-row prisoners are high in minorities even compared to the population of prisoners who commit similar crimes. This isn't about how commits more crime; it's about the fact that a half-decent lawyer gets you off a death sentence unless you've done a really nasty crime.

    7) Again, problems with the system apply to the penalty. You shouldn't have a penalty that is so unevenly applied.

    I'm an atheist. I don't believe in God, I don't apply any special value to life other than mine. OTH, I believe in humility (you obviously don't, you arrogant nosewipe), avoiding making irreversible mistakes (last time I looked, nobody ever came back from the dead, not even Jewish carpenters), and a belief in the adage (that originated in the US) that "it's better to let a guilty man go free than send an innocent one to jail". And at no point did I say "People are special" or "Life is sacred".

    Actually, my biggest problem with the death sentence is that it doesn't work. It's always put in as a "tough on crime" measure - but it doesn't provide any deterrence. It doesn't save any money - the appeals process for most death row cases costs more than the life-with-no-parole option. It doesn't just get the guilty - too many death row victims have been vindicated after their deaths, and even the ones who get reprieved during the appeals process shows the problems with the system. And without exception, in the US, it's put in (and taken out) as a political stunt, rather than a serious law enforcement measure, with set goals for success or failure that would lead to rational debate.

    And, BTW, as someone advocating for a violation of the US constitution (the whole "lack of rights" bit), you are technically guilty of treason. Unfortunately, in the US, treason is only a capital crime for military members, so if you want to see yourself put to death, you'll need to self-enforce, so to speak.

  13. Re:Heh on The Pirate Bay Files Suit Against Big Media · · Score: 4, Informative

    What's wrong with the death penalty? Ah, let's see...

    1) Human error. Unfortunately, being innocent isn't a guarantee that you won't be convicted of a crime (especially if you are poor and black). So there's a chance that a person killed by the state was not guilty of the crime. With incarceration, you can set them free and compensate them somewhat for the mistake. With a death, you can't.

    2) The religious angle. Many religious types believe that incarceration gives the prisoner a chance to earn redemption and avoid eternal punishment. (This works both ways - one long-held reason for execution was to allow a higher judge to determine the right sentence)

    3) The economic angle. Contrary to general opinion, prisons can and do make money. That's one reason why private industry lines up to run prisons. Why kill off perfectly good slave labour? Remember - the advantage of slave labour is that the shirts made on Friday aren't worse than the shirts made on Monday!

    4) Human rights factors. The US is the only western country, and one of three in the world, that will execute children and the intellectually impaired. Okay, by the time the appeals process goes through, the child is now an adult, but killing someone for a crime committed when they were 12? Seriously.

    5) The scattergun approach. Look at the sort of things you can get the death sentence for in the US. Heck, if you're driving a car and a passenger decides to shoot down someone, you can get the death sentence.

    6) The racist angle. The vast majority of people on death row are racial minorities - way out of proportion with the general prison population, or even the subset who committed similar crimes. Why? Because juries are more likely to give the death sentence recommendation to blacks and Hispanics. The lack of an objective and impartial set of criteria makes the use of the death sentence subject to these distortions.

    7) The poverty angle. When was the last time someone who could afford their own lawyer got sentenced to death in the US? The fact of the matter is that far too many of these death sentence cases are handled by overworked public prosecutors. If you've got a competent lawyer, and a death sentence looks like a strong possibility, then you will nearly always end up doing a plea bargain, resulting in an incarceration instead (often for a lesser crime, like manslaughter).

    I could go on, but... I just don't want to. :)

  14. Re:What will the Chinese find on the moon? Rocks. on Will China Beat the United States Back to the Moon? · · Score: 3, Insightful

    Except you need to think about the military situation. However controls the moon will control the space around Earth. Without control of space, and near-Earth-orbit, much of the US's military might just vanishes.
    Goodbye GPS. Goodbye launch-detection-systems. Goodbye spy satellites.

    There's also a lot you can do with rocks. For starters you can throw them. Go read some Heinlein.

  15. Re:First ping on UK Police Cracking Down on Broadband Theft · · Score: 1

    Well, in Australia, the police can fine you for leaving your car unsecured.

  16. Re:Imaginary excuses. on Piracy More Serious Than Bank Robbery? · · Score: 1

    Why limit yourself to losses? It's worth noting that big selling movies and music have higher piracy rates. This seems to run counter to the logic that piracy hurts sales. In fact, the various bodies concerned have never been able to demonstrate high piracy rates having a measurable impact on sales except for when an overly-hyped product (which would probably have had high "first-day sales") is pirated before release, and is evaluated as a dud.

    Contrawise, there have been several documented instances of piracy being valuable marketing, resulting in increased sales.

  17. Re:What a Power Trip! on Is Videotaping the Police a Felony? · · Score: 1

    RTFA - it's not illegal to film police. It's illegal to file _people_ without consent, under that wiretapping law. Police have a particular exemption, for use in a particular circumstance.

  18. Re:Some Quick Thoughts.... on A Field Trip To the Creation Museum · · Score: 1

    Well, as far as Galileo is concerned, that is not the case. Galileo was being attacked by the Inquisition for his belief in heliocentrism. In order to avoid persecution, Galileo went silent on the subject for a long time. When Pope Urban VIII (a friend of Galileo) was elected, Galileo decided to revive the book he'd been writing - the Pope asked him to cover both pro and con viewpoints, and thus was the "Dialogue Concerning the Two Chief World Systems" published with Papal approval.

    The book had the side effect of highlighting the logical errors in the Aristotelian viewpoint. This made the Pope (who was clearly identified with the Aristotelian advocate 'Simplicius') the target of jokes. Pope Urban, pissed at this, removed the papal approval, and the the Inquisition _renewed their earlier attack_ on Galileo. Repeat after me - the Inquisition were after Galileo prior to the book being published.

    At his trial, Galileo was not required to apologise to the Pope. He was required to recant his position that heliocentrism was truth, he was imprisoned (commuted to house arrest), his book was banned, and all future books were also banned. The only book Galileo published after this was published (his best and most important - 'Two New Sciences' - the book that earned him the label of 'Father of Modern Science') in the Netherlands, where the the Inquisition had little power. Ironically, this book had very little in it that would have been offensive to the Church.

  19. Re:Just do this test for me... on A Field Trip To the Creation Museum · · Score: 1

    The US isn't the only country in the world to have freedom of religion, you know.

  20. Re:Exclusiveness on A Field Trip To the Creation Museum · · Score: 1

    Yes, but we didn't pay him to do it. :)

  21. Re:It's funny. . . on A Field Trip To the Creation Museum · · Score: 1

    Now, supposedly he wanted us to have free will.

    No, he didn't. That's why he warned Adam and Eve not to eat from the tree-of-knowledge.

    At best, free will is something "given" to Adam and Even when they were kicked out as a consolation prize. But God would have preferred for Adam and Eve to stay ignorant as the animals they named.

  22. Re:Confused on A Field Trip To the Creation Museum · · Score: 1

    This is an interesting point - Creationism vs Christianity. Let's run with it for a bit.

    Pretty much by definition, if you take the Bible as literal truth, you're a Creationist. If, in particular, you take Genesis to be more fable and metaphor than truth, you're not. However, in order to be Christian, you must believe that Jesus Christ existed, that he died on the cross as redemption for our sins, and that he was then resurrected (believing if Jesus was God or the Son of God is optional).

    So - what sins exactly was Jesus redeeming? Not the sin I would commit if I went out and killed my neighbour, that's for sure. No, Jesus was redeeming only the "Original Sin", giving people a clean slate to fill up as they felt fit. But what was the "Original Sin"? It was the sin of eating the tree of knowledge, that got Adam kicked out of the Garden. So if you are not a Creationist, and you don't believe in Genesis, what exactly do you think Jesus died for?

    Science and theology are not diametrically opposed. Science and Christianity - well, that's a different question.

  23. Re:Factually inacurate on A Field Trip To the Creation Museum · · Score: 1

    That's the gist of the Church of the Lightbringer (the slightly less controversial name for the Church of Lucifer). They argue that Lucifer, who was God's first creation, and placed above the angels, saw a potential in Man that Yahweh was actively suppressing. He took exception to this, and took the necessary steps to unlock that potential. Yahweh, pissed at Lucifer, kicked Lucifer out of heaven, kicked Man out of the garden, and started a massive propaganda war.

    According to the Church of Lucifer (who are _not_ devil-worshippers), God and Lucifer are engaged in an eternal struggle - God wants to keep Man suppressed and subservient, Lucifer wants to see the human potential realized, and Man to be able to join the ranks of the angels and have _true_ free will. One part of the evidence that they cite is the long history of various Christian organisations, from the Catholic church up, have of actively opposing scientific observations.

  24. Re:One thought on Chairbot Walks You Around While You Sit · · Score: 2, Interesting

    Correction - G8 has some rioters (no numbers given in the linked article) who decided to charge a police line. There's not even the remotest suggestion here that the police suppressed an otherwise peaceful protest. In an article linked from that article, there's a mention of how police used tear gas and batons to break up a group of rioters who "threw bottles, fire crackers, rocks and Molotov cocktails" and "broken up paving stones to use as projectiles and overturned and torched several vehicles". At least 146 police were injured by these rioters. As further evidence of the lack of police instigation, several other truly peaceful protests had no incidents.

    Peaceful protests don't break down into riots. Peaceful protests don't have the protesters being caught on film throwing Molotov cocktails and smashing up cars with crowbars.

  25. Re:10% of $product market... on A Million Zunes Sold · · Score: 1

    Pay attention to the math... I don't have to half the Zune sales, because I doubled the Apple sales.

    Furthermore, who says that Apple's "sales" numbers are "to consumer's pockets"?