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  1. Re:Typical and misguided on A Way to Save Hubble? · · Score: 3, Interesting
    Shuttle mission cost half a billion dollars in the past. How much would it cost to build a robot to do the simplest things to extend Hubbles life?

    What exactly would Hubble need to keep working? Boosting to a higher orbit, because its current orbit is decaying? And Hubble's gyroscopes are wearing out, and will need replacing.

    So, how expensive would it be to build a robot that gently grabbed ahold of Hubble, gently boosted it to a higher orbit?

    Would it be possible for a robot like this to use its own gyroscopes to keep Hubble stable?

    Yes, I know there are also new lense modules, and similar, but they would require an astronaut to install them. Well, maybe they can wait until the safer replacement for Hubble is ready.

    Could the robot have enough fuel to move Hubble to orbit next to the ISS?

    There is supposed to be a replacement for Hubble, that may be ready in ten years or so. But it might not be ready. And it might not work. Hubble works. Maybe they should keep Hubble until they know the replacement works...

  2. Re:Definitely ISS debris on Space Station Slowly Falling Apart? · · Score: 1
    I am thinking out loud here...

    Fasteners and labels that come loose will, initially, be moving at the same velocity as the ISS, agreed?

    During the 18th Century, during the days of sailing ships, ships could be becalmed for weeks. And they would be floating in a cloud of their own debris, kitchen scraps, empty casks, and, um, " admiral brown ". A ship the size of the USS Constitution would have a crew of 400. Imagine how much "admiral brown" she would be circled by following just a few days of no wind.

    If the debris seen from the ISS had the same surface to mass ratio as the ISS presumably it would just stick. But the ISS is hollow, and it has these big solar panels. So it would a fairly extreme drag, compared with mundane items like fasteners and labels.

    What happens to debris with a different drag than the ISS? If it has less drag it remains in a higher orbit than the ISS. If it has more drag than the ISS then it will migrate to a lower orbit than the ISS.

    If the debris is in a slightly higher orbit or a slightly lower orbit than the ISS then its period will be different. The way I see it the ISS will diverge from its debris. And the debris would form a smear, not a cloud.

    So, when could a peice of debris impact the ISS at any kind of velocity? It seems to me that the debris might impact the ISS when it lapped the ISS, or vice versa. If their orbits diverged enough for, let's say 10,001 orbits of the ISS to take the same time as 10,000 orbits by the debris, then they would be over the same position on the Earth, at the same time. Would the debris be in a high enough orbit to completely miss the ISS? By my back of the envelope calculations, the relative difference in orbital velocity would be something like 4 km per hour.

    If it took fewer orbits for the ISS to lap the debris, the relative difference would be greater. But with a greater difference in relative velocity there would be a greater vertical displacement.

  3. gambling on the future of carbon sinks on Arctic Ice Holds Much CO2 · · Score: 1
    No one ever compares the actual amounts of energy or chemicals, nor do they estimate the CO2 sinks in the world that are natural.

    There is the trap of killing the messenger, upon hearing bad news. You aren't falling into this trap, are you?

    So, what are these carbon sinks that you want us to gamble on?

    It seems to me that most carbon sinks that are put forward only work in the short term. Can we lock carbon up in forests? Temporarily, maybe. Forests burn. Or trees fall down, and decay, and their carbon is released as CO2 as they rot. If we harvest the wood, and build something out of it, like a house, well that house gets burned down, pulled down, termite infestation, dry rot. What is the average life-time of a house built today?

    This is not a long term solution.

  4. swapping out as a diagnosis technique on Good, Affordable PC Diagnostic Software? · · Score: 3, Interesting
    swapping out can really suck as a diagnostic technique. More precisely, it can really suck if not done very thoroughly. Horror story follows.

    There was this little mom and pop computer shop, where I bought some stuff, and my buddy bought a whole computer, circa 1993-94. My buddy paid $800 for 16 megs of RAM. And he paid $250 for a honking big tower case, with wheels, and hinged panels, and almost a dozen external bays.

    That honking big case was a honking big mistake. He never populated those bays, and it was too bulky to carry on public transit. Well, I had a car, and he didn't. So, when he had hardware problems he would beg me for a lift.

    I can't remember how many trips we made to this store. A bunch of them concerned his flaky hard drives. The fellow replaced the drive, at least once.

    Well, one time my buddy asked me to take his computer to this store for him. And this time I watched the owner's diagnostic technique. The first thing he did was take the drive out of the big honking case, and put it in his test rig. He also confessed to me that he wasn't replacing the drives any more, he would just test it, and if it was okay he was telling my buddy he had replaced it.

    When I got the computer back to my buddy's place, I opened it up myself. I found that one of the pins on one of the power connectors had come loose. So it was only making intermittent connection. And this was causing intermittent problems.

    Diagnosis through swapping out components failed here.

  5. Another reason for Ellison to be agressive on Harlan Ellison Can Sue AOL Under DMCA · · Score: 1
    Here is another reason for Ellison to be agressive in his pursuit of the unauthorized copies of his work. Various correspondents here have made unkind comments about Ellison's character, suggesting that his is being greedy and unreasonable, and already has enough royalties.

    Well, when I looked at this recent article on electronic copyrights in the most recent RISKS digest I was reminded of the Ellison story.

    The author of this article objected because the stolen version was corrupted, and, in his opinion, inferior, to his original. And additionally because his original was unattributed.

  6. Cannibalizing hardware found put out to the trash? on Which Screw Goes Where? · · Score: 1
    Been there, done that.

    The last time I did this I found a pile of 486s put on the curb of the main street of my city. It was a couple of days before Christmas, so even though it was about 9pm on a Saturday night I was passed by a lot of pedestrians. I was sure that a fair number of them thought I was doing something illegal.

    I am not sure whether a bored cop wouldn't have seen it the same way.

    They each contained 40 megabytes of 72 pin RAM -- hard to get a hold of for a reasonable price, if you rebuild older computers. And they contained 1.2 Gig drives. Puny by today's standards. But not worthless.

    I carried one computer home, and took the RAM and hard drives from two others. Worked fine. The drives had no bad sectors.

    When I cannibalize an older computer I always screw the case back on. I wouldn't want some kid to get cut on the sharp edges found inside.

    As per usual no effort had been made to erase the contents of the hard drive. However the cases had been sprawpainted with fluorescent orange spray paint.

    Should the owners of these computers have been worried that they were throwing out toxic waste? If I cannibalize parts should I worry that I should be assuming some of the burden of making sure the computer gets put into the appropriate waste stream?

    These computers also contained their original 100 megabyte drives. Disconnected. Clearly whomever put in the 1.2 gig drives had been too lazy to deal with them at the time.

  7. Allision sensors anyone ? on Expert Says Glass Is Major Threat to Birds · · Score: 1
    Maybe what is required is an allision sensor ? When it detects that a bird is at risk of alliding with a window it flashes a light, hoots a horn, or some other thing that might warn the bird away.

    (What is an allision? When something bumps into a stationary object it is an allision, not a collision.)

  8. Re:What about radio control? on Robots for No Man's Land · · Score: 1
    So have the control operations well distributed...

    I suspect that the scheme of robot armies shares the same fundamental weakness as a National Ballistic Missile Defense. Namely that the countermeasures to defeat it would be a lot cheaper than the weapon itself. Maybe you can keep the controllers safe back in HQ. I suspect that it would be very easy to disrupt the communication with remote controlled robots. What about flares that dispensed chaff? Tactical nukes? Not only does a nuke generate an electro-magnetic pulse, that can burn out nearby electronics, but I believe the mushroom cloud itself is highly ionized, and disrupts radio communications.

    Your suggestion reminds me of a Scientific American article. Scientific American did an article analyzing the command and control system for America's nuclear armed minutemen missiles. IIRC The minutemen are organized into groups, with 10 silos and five of those deeply buried command bunkers.

    That old movie Wargames, and many others, have shown us the countdown system, where the two officers in each bunker break out the safe, make sure that the command code matches the one in their secret binder, and then both turn their keys at the same moment.

    Well, the mission of the officers in the bunker also included a protocol to follow if they were cut off from headquarters. There were conditions where they were required to launch their missiles if they lost contact with HQ, to deal with the situation where HQ has already been destroyed.

    The authors of the Scientific American article were critical of poorly thought aspects of this protocol.

    IIRC the five bunkers were hooked up to all ten silos. And, I think one of the problems with this system was deciding what to do if an even number of surviving bunkers could not agree on what to do.

  9. Re:Friendly fire due to misuse of GPS? on Robots for No Man's Land · · Score: 1

    I read somewhere that something like 20% of the GIs used to inflict something like 80% of the enemy casualties, because most GIs didn't really aim at anything, just fired in the general direction of the enemy.

  10. Friendly fire due to misuse of GPS? on Robots for No Man's Land · · Score: 1
    ...almost all friendly fire casualties in Afghanistan and Iraq are due to idiots who misused their GPS...

    Really? Interesting. And yet haven't there been friendly fire casualties in earlier wars. I read figures of the rate of friendly fire casualties in previous wars. As I recall, I was shocked by how high they were... IIRC close to half the rate in Gulf War 1. And those earlier friendly fire incidents preceded the use of GPS.

  11. Caring about the Geneva Convention on Robots for No Man's Land · · Score: 1
    You have triggered one of the bees in my bonnet. The popular film Courage under fire portrays a serious war crime.

    Heroic Meg Ryan is the plucky pilot of a medevac helicopter -- one clearly marked with a prominent red cross. Yet she instructs her door gunner to fire upon an Iraqi tank.

    This is a war crime.

    The convention is that a tent, a ship, a truck or a helicopter bearing the red cross is an unarmed noncombatant. The convention is that those in a red cross vehicle are all working to preserve life. You are not supposed to fire on them, because they are working to preserve life. And you are not supposed to fire on them because you are supposed to be able to rest assured that they are unarmed, and can't fire on you.

    So, why the heck does her medevac helicopter mount a machine gun? And why the heck is she giving the order to attack?

    As I exited from the theatre I said to my companion, someday soon there will be a war, where the red cross will not be respected for being non-partisan, and they are going to be shot at. And this film be a contributing factor.

    I didn't hear of a single movie review where someone pointed out that her heroism included committing a war crime.

    So, maybe you should include America in those nations that don't care about the Geneva convention.

  12. Re:Does war become cheap? on Robots for No Man's Land · · Score: 1
    Except that these private armies brought misery upon the rural populations that populated the warfare areas; the quarreling lords often didn't have enough money to pay for the soldiers so these would redeem their take on loot and spoil. Your description makes it look like some kind of World Football Championship peasants followed on TV. Nah, they had their villages put ot flames, the wives raped and the livestock eaten... and epidemics and summary excecution... war is war... close to home... across the world... an aseptic radar image or a rotting trench... I'd like to live without it.

    Yours is a common view. But I did some reading about this change. And I believe you are mistaken.

    War was hell on peasants. But modern war, of which an example would be the wars arising from the French Revolution, was much worse.

    The occasional times when the lord didn't have enough money to pay their soldiers, and the soldiers would strip the peasants bare of food? This became the standard operating procedure.

    Think "animal husbandry". Those quarreling lords thought of the peasants in a way similar to the way a farmer thinks about livestock.

    So, their wars were characterized by limited goals; fought by small, "professional" standing armies; who were fed by a "baggage train".

    The armies of the new French Republic were not fed by a baggage train. Stealing the peasants food was not the result of an occasional breakdown in the lord's finances. This was standard operating procedure. When they began an operation the troops were issued with a string of super-hard breads, one for each day.

    One of the side-effects of not dragging their rations along with them was that the French Armies could march about 50% farther per day than a conventional army. This was very important. Manuevering for position prior to the fight is half the battle. This is one of the explanations for their early successes.

    Your petty prince could only maintain a small standing army. A standing army is expensive. They eat like horses, even in peace-time. Maintaining one a lot bigger than your neighbours, during peace-time, could cost you the next war, because it would drain your treasury, and you wouldn't have the cash to pay for a real fight when it came to war.

    A professional standing army took a long time to train. But this was important. You needed them to be very disciplined. One of the reasons was you needed them to be disciplined enough not to go wild if you won a battle, and kill all the peasants. Your victory was worthless if the land you won was empty of peasants, because your army killed them, or starved them.

    Another reason that the war of your petty princeling could be harder on the populace than a modern war is that when modern wars are fought over an idea then they get more brutal. Nationalism, patriotism, communism, GOD -- people are more brutal when they fight for these ideas. Perhaps braver too, more willing to give their lives to the cause.

    As to the question whether a smaller army, composed of highly trained volunteers with high morale, is better than a larger army composed of conscripts with low morale... Well, they say Generals always want to refight the last war. That high morale volunteers were better than a larger body of low morale conscripts, do you think this was a lesson of Vietnam?

    Fighters willing to give their lives? I would say they would all be fighting for an idea. It makes them dangerous opponents. It would be a mistake to think "islam" here. Timothy McVey's group, the Tamil Tigers, the IRA -- these groups can all find members willing to go on suicide missions.

    I am going to repeat something important. War is Hell, even the smallest ones, if you are one of the innocent bystanders who ends up suffering. And they all have my sympathy, no matter what size the war they suffered in.

  13. Re:Battletech : 2010 on Robots for No Man's Land · · Score: 1
    The US army's stryker only come equipped with a machine gun. The USMC uses the same basic vehicle, as does the Canadian army, and the Australian army, equipped with a variety of weapons. The army's strykers don't mount those turrets because the extra few inches mean they won't fit in anything but the largest transport aircraft. With the little machine gun turret they fit in the standard, more common, medium sized transport aircraft.

    Note particularly the recon mast carried on the Canadian vehicle I have linked to.

  14. We don't live in a 3 body universe on NASA to Reconsider Hubble Decision · · Score: 1
    Of the five Lagrange points, only L4 and L5 are stable enough for their to be a risk from accumulated dust and rocks. The Lagrange points are solutions to the three body problem .

    But we don't live in a three body Solar system.

  15. Re:Need paper receipts on Maryland Electronic Voting Systems Found Vulnerable · · Score: 1
    The legislature is considering a measure requiring a paper backup to verify computer vote totals. "I want to have confidence beyond a reasonable doubt," said Del. Anne R. Kaiser (D-Montgomery). "How else do we do it?"

    The legislators have it wrong here. The paper should not be a " backup ". The paper should be the ballot. The voter sees it. It provides the audit trail. But then the voter surrenders it.

    Municipal elections here, in Toronto, use a ballot that is letter sized. When you surrender your ballot, it is in a sleeve, to protect your privacy, and fed into a scanner, which tabulates the vote. But the paper ballot is still the final arbiter. As it should be.

    What is the value of using a machine at all then? Well, in addition to reporting to HQ earlier, the scanner can determine if the voter made a mistake, like voting for two candidates at once, and be given an opportunity to submit a correctly formed ballot. I don't know if this step is performed -- because of the tradition of voters purposely submitting a spoiled ballot, to register that they do not respect any of the candidates.

    Internet voting? Voting by phone? Personally, I can't see these working so long as we practice the secret ballot. The voting receipts that some correspondents have suggested eliminate the idea it is a secret ballot.

  16. Re:Ummmm....bad idea economically on Growing Your Own Gold · · Score: 2, Insightful
    Um, if gold were as common as, say, iron, or aluminum(*), don't you think we would still be using it? It would still make beautiful jewelry. It would still be an excellent conductor heat and of electricity.

    (*) Thirteen percent of the Earth's crust.

  17. Georgius Agicola said it first on Growing Your Own Gold · · Score: 4, Interesting
    I have a copy of De Re Metallica, the 2nd book on metallurgy and related arts published outside of China. Rather I have a translation of it.

    Written in 1556, by a German, in Latin -- it covered labor management, metal working, ore processing, mining and prospecting .

    Agricola explained that gold grew in the ground, like the roots of trees. So, he said it first.

    (The first book was entitled Pirotechnia, written in Italian, in the city of Siena, in 1540, by one Vannocio Biringucio.)

    (I know Agricola doesn't sound like a German name. His real name was Georg Bauer. Like Nicholas Copernicus he translated his name into Latin. People did that back then.)

  18. Re:You win, don't pay on "DVD-Jon" Demands Compensation · · Score: 1
    ...Also, if the little guy sues the big corp, and loses, the little guy's lawyer gets $0, and the little guy doesn't owe anything).

    Hey! Doesn't that sounds a lot like Darl's business plan?

    [1] Launch frivolous far-fetched lawsuit, with extremely nebulous justification, just because someone has deep pockets.
    [2] Attack anyone who points out the fanciful nature of your suit.
    [3a] If the suit fails, your firm is bankrupt, so you don't have to pay damages, or your lawyers.
    [3b] Make enough of a nuisance of yourself that the deep pockets settle with you, just to shut you up. Yeah! Profit!
    [3c] In the unlikely chance you win -- Yeah! Even bigger profit!

  19. American democracy... on Machine Vision Patents Thrown Out · · Score: 1
    You Americans! You are so funny . You like to talk like you have the franchise on understanding democracy, yet so many of you don't understand it at all.

    When a guy runs for office, and he is able to say something new, something other people aren't talking about, and get the public to consider and debate the issues he raised, then his campaign is a success.

    Dean got people talking about the war. So his campaign was a success.

  20. Re:Question for a rail enthusiast... on A Modest Model Railroad · · Score: 1
    The Musuem you speak of is the Museum of Science and Industry in Chicago...

    Thanks for the suggestion. Here is the actual link. (You had a spelling error in your link.)

  21. Re:A True Historian on A Modest Model Railroad · · Score: 1
    Now don't hold back! Tell us what you really think!

    What? He's a gun toting nut case that loves himself,

    Ah. A gun nut. That is not that uncommon in the States, is it?

    thinks he can channel the gods (especially the god of sex)

    Channeling the god of sex. Hands up everyone who would channel the god of sex, if they could?

    seems to think that he is the most important person in the community without actually having done much that is useful?

    I think ESR's biggest contribution are the articles he wrote, which came at a key moment.

    Now I didn't agree with one passage from his Halloween document. The original leaked Microsoft memo said (paraphrasing) " Linux doesn't have the same vulnerabilities as our traditional enemies. One weakness however is that the Linux volunteer's efforts are driven by their egos, and their egos can be turned against them. "

    I thought this was a perceptive criticism -- one to be taken very seriously. But ESR discounted it without addressing it at all.

    Good thing Linus is a sweet-natured modest guy.

  22. Waste silver is valuable on Is Your Silver-based Thermal Paste Really Silver? · · Score: 1
    I worked in an old-style (pre desktop publishing) publishing house. We used the old style phototypesetters, the ones that used photopaper that had to be developed in a dark room. And we had special recycle bins that were only for used or waste photo paper. The silver on it made it valuable -- worth recycling even back in the days when few things were recycled.

    In addition heavy metals are toxic waste. Here is a web-page devoted to Argyria -- the medical term for silver poisoning. What the heck are you doing throwing something out that is both toxic and valuable?

  23. Lab testing expensive? on Is Your Silver-based Thermal Paste Really Silver? · · Score: 1
    Lab testing is expensive. I doubt the margins on this product are huge, so it's not economically viable to test every batch in an external lab.

    Is it? Perhaps, at an official lab where someone has the right certification to write you up a formal report -- one that could stand up in a court of law.

    But the fine article describes the OC people borrowing some equipment from their local jewelers. How expensive would it be for OCZ to take a couple of tubes over to the local jewelers every so often, and ask him or her to do an informal test?

  24. Pressurizing the oil deposit with waste CO2? on US Army Pursues Hydrogen Fuel Concepts · · Score: 1
    One of the complications with the oil industry is that to maintain the pressure within the oil deposit they pump in something else. They are never able to fully extract all the oil from an oil bearing deposit. The "gusher" that is so photogenic occurs when the deposit is under high pressure. But there will still be lots of oil down there, once the pressure has dropped.

    So they pump some other fluid into the deposit to keep the pressure up. Water is what is commonly used. But fresh water is at a premium nowadays too. And oil is commonly found in arid environments.

    Experiments have been done pumping carbon dioxide gas back underground to keep up the oil pressure. Great idea, except how do you ship a high volume of CO2 to the well-head? Well, if you produce CO2 at the well head, as a byproduct of extracting Hydrogen, there you are.

    Who knows, maybe in a thousand years we may find a use for all that CO2 we stored?

    As for the difficulty in shipping a gas back from the wellhead? A difficult problem. I believe that there are still oilfields that burn off the natural gas that comes out with oil, rather than capture it and transport it back to be put to a useful purpose.

  25. Re:Digital watch a step backwards on Forgotten Electronics of the 70s and 80s · · Score: 2, Interesting

    I read that all countdown timers, in all the Bond films that featured them, were always stopped showing 0:07 seconds remaining.