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User: smellsofbikes

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  1. Re:unintended consequences... on Millimeter-Wave Weapon Certified For Use In Iraq · · Score: 1

    Boy are YOU an optimist. I hope you're right, but 'the best use' is rarely what happens. The US develops this, China reverse-engineers it next week, and I'll bet they won't bother with much training or lectures on restraint.
    Even in the US, it's really easy to imagine this being misused. If you have a bunch of peaceful protesters standing around blocking a road, well, hey, this won't actually *hurt* them, so why not use it? coz otherwise a bunch of police are going to have to go out and actually arrest people and take them to jail and get pictures published of them dragging people off -- very mediapathic -- whereas with this, suddenly everyone just decides they want to go somewhere else, fast. So much for a staple of peaceful protest.
    Plus, it's easy to imagine the equipment being miniaturized until it fits in a police car, or five, or all of them, and it's not like a crowd of people, no matter how pissed, can destroy a couple dozen police cars unless they're pretty heavily prepared for serious violence beforehand.

    It's not like any of this kvetching is going to change things: it exists, I'm sure it's going to be used. I'm just pointing out how it can be misused and as other people have said with respect to tazers, I'm sure it will, and as soon as the people who have them can manage it.

  2. Re:No way! on The Case for OpenID · · Score: 1

    >Stop requiring registration for moronic things! I don't want to give you any personal information to post in a damned blog!

    I don't want to have to carry keys to unlock my house and car doors...
    And I don't want to require people to give out personal information to post in my blog but unless I do so, it's filled with spam postings and morons gabbling about politics.

  3. unintended consequences... on Millimeter-Wave Weapon Certified For Use In Iraq · · Score: 2, Insightful

    On the one hand, it beats the hell out of using machine guns for crowd dispersal.
    On the other, because it doesn't (apparently) kill people, armed forces will be *much* more likely to use it to disperse people, instead of trying to do things that keep people from rioting. Technical solution to non-technical problem isn't a solution, it's a treatment.
    Any bets on whether this is already in use for interrogation?

  4. Re:Tailgating on Detecting Tailgaters With Lasers · · Score: 1

    I've known people with subcompacts to put big mirror segments in the back windows of their cars. It's only upsetting to people whose big lights are up high.

  5. Re:Tailgating on Detecting Tailgaters With Lasers · · Score: 1

    Uhhhh, I modded the car to burn propane?
    No! Solar! I glued hundreds of old calculators all over it and hooked their solar power cells to an electric engine...

  6. Re:Tailgating on Detecting Tailgaters With Lasers · · Score: 1

    Oh, so *you're* why I always store 300 kilos of concrete blocks in the trunk of my car.

  7. coilgun, spotwelder, cool laser-alignment tool on What's the Coolest Thing You've Ever Built? · · Score: 1

    I build a lot of stuff.
    It's easy to make a coilgun. You take a cardboard tube, like wrapping paper comes on, fill it with 1/8" welding rod of various lengths so it's solidly packed at the bottom and only maybe 1/3 get all the way to the top. You wrap an *enormous* bundle of transformer wire around the base, where the rods are solidly packed -- like 400 turns of 18 ga wire. You point it upwards, and put a ring (best if aluminum, okay if copper, so-so if steel) around the tube and slide it down to the bottom. Then briefly plug the coil into the wall. The ring will shoot off the end like a gun. For extra credit, use a 2N2222 transistor driving the coil of a big relay, and you can interface it to your computer to optimize the AC on time. Double extra credit for adding a big capacitor to tune it for maximum oomph. Mine will put big dents in 3/4" plywood.
    It's pretty easy to make a spotwelder. I used Kurt Bjorn's design, with my own construction techniques (ie scrap lumber) and the same transistor-and-relay interface that I use for the coilgun, so I can time the welds. It welds stainless steel like butter. I wrote visual basic and C programs that have lookup tables so I can tell it that I'm welding 14ga stainless wire and it'll know the right on-time to get a good weld. (Eventually this will be part of a LEGO-based welded chainmail making machine.)

    But I think the coolest thing I had a hand in was a laser system at a now bankrupt place. We were drilling thousands of tiny holes at once, by firing a large beam (10cm x 10cm) through a multi-lens element. The beam had to be perfectly perpendicular to the lens. We had an alignment tool that consisted of a 1024-element CCD and a laser diode, that we'd shine off the lens and see where it bounced against the CCD, so we had a precision of 1/2048. (Error is doubled because of the reflection.) It wasn't sufficient -- and we'd paid $4000 for the device. Well, the laser went through 7 mirrors before it got to the lens element, and the top of the lens element was flat... so I put a front-surface mirror on it, to reflect the beam directly back the way it came, and put an index card over the laser output, with a hole punched in it. So the laser goes through all the mirrors, hits the reflecting mirror on the objective lens, bounces *back* through all the turning mirrors, doubling its error with each bounce, and you see a nice spot on the index card where the reflected beam is. You visually align the spot with the hole in the index card, and you then have your lens perpendicular to the beam to an accuracy of the diameter of the hole divided by (the beam path length * 2^7). More accuracy than we needed, for a cost of a front-surface mirror (which we already had), a paper punch, and a recurring cost of index cards (because they burst into flame after about 20 seconds.)

    Right now I'm working on making a solar concentrator that'll boil water and drive a steam engine, since I have no shortage of sunlight and at high altitude water boils quickly. It's way cheaper than solar cells and it'll go "fphoof! fphoof! fphoof!" as it runs. It'll be awesome.

  8. Re:Mortar on Pyramid Stones Were Poured, Not Quarried · · Score: 1

    I was actually just reading some blacksmithing books that are kind of old -- when they refer to "the recent war" they mean the Civil War. One of the things I found interesting was that if you find a person who talks about different kinds of hammers, you'll see someone spell a round-ended hammer either 'ball peen' or 'ball pein'. As recently as 1880, they spelled that type of hammer 'ball pene' or 'ball pean'. Two completely different spellings, competing for #1. Anyway, in there a lot of blacksmiths were arguing that it was trace elements, by which they meant (although they didn't know it) molybdenum and chromium, that made steel hard, and that carbon was an unavoidable impurity from the blast-furnace process. (I don't think that oxygen-decarburization was widely known, if at all, at that point.) I'm just always surprised by how recent the vast majority of our knowledge is. As someone else said in this thread, it was only in the 1930's that we found how to make good concrete. You could find biochemists who argued that genetic information had to be carried in proteins into the 1960's, and geologists who said the idea of continental plates, that moved, was complete rubbish, well into the 1970's. We still know so little.

  9. Re:Mortar on Pyramid Stones Were Poured, Not Quarried · · Score: 1

    As I recall, the outer layer was marble or particularly white limestone, and must have looked incredible.

    If you read old alchemy stuff, it's amazing they ever discovered anything. Then again, before they knew what elements were, I can't imagine anyone doing any sort of research at all. They couldn't even agree on what sulfuric acid was, much less what its purity was. It's amazing anyone ever got anything useful done. I *think* I remember reading that as late as the 1870's people weren't sure that carbon hardened steel, or whether it was something else entirely and the carbon was just another contaminant.

  10. Re:Mortar on Pyramid Stones Were Poured, Not Quarried · · Score: 1

    That makes you wonder what sort of written instructions they had, if any, to be able to retain knowledge about precise mortar formulation. For that matter, imagine trying to make a precise formulation when your instructions are "one point five buckets of camel dung..." Ugh.

    One very good reason to have space between stones, to dry-lay stones in general, is for drainage. That's one reason it's still used (aside from simplicity) -- apparently, a dry-laid retaining wall will last longer in frost-heave situations because it'll keep the dirt behind it somewhat drier. (Says a friend of mine who does walls like this for a living.)

  11. Re:Thermal stress on Pyramid Stones Were Poured, Not Quarried · · Score: 1

    A: I wish I did: he died years ago. He had some fantastic stories. Both my grandfathers did, actually, about rebuilding Indian motorcycles with pieces of wood as engine parts while riding across the country, or getting arrested for appearing in public not wearing a shirt.

    B: Okay. Most people don't, and I probably should've just let it go. I wonder if there's a definition of brittle, now...

  12. Re:Thermal stress on Pyramid Stones Were Poured, Not Quarried · · Score: 1

    My grandfather told me about the first highways in Iowa, in about 1915. Laid with continuous concrete, in dead straight lines, between cities tens of km apart, during early spring. At the height of summer you'd drive along the highway a couple km, then pull off to detour around the head-height ridge of concrete from the thermal expansion, get back on the road, and keep driving. So it's not like engineers always think ahead... I see the same thing on bike paths pretty frequently, which (I think) is why newer bike paths tend to be sinuous rather than straight.
    by the way, asphalt is less brittle, but more to the point it's both plastic *and* elastic. I think concrete is only elastic and not very much of that.

  13. Re:A little insight on Pyramid Stones Were Poured, Not Quarried · · Score: 2, Informative

    Note that Navajo and Zuni (and many, many other prehistoric civilizations) drilled holes in stones using pieces of straw. Which are, y'know, six orders of magnitude softer than stone. They did it using abrasives. (sand and spit, as it happens.) There's no rule that the Egyptians couldn't do the same thing. It's quite possible to dry-fit stone, using nothing but other stones, to the point you can't fit paper between two of them: you hit the high points, rub the stones together, see where they rubbed, repeat until you're at the limit of resolution, which is determined by the surface marking compound. In their case they probably used the dust from the hammering. It takes a long, long, long time but it's very effective at making astoundingly tight walls. Now, it's a *lot* trickier to rub 2000 ton stones together. However, it's possible to make plates that are nearly perfectly flat, again limited by your surface marking compound, by the three-plate method. You rub plate A and B together until they look pretty flat, then plate B and plate C, then plate C and plate A. If you do that for long enough, all three will be true flat. (There is a possible exception to this, that a mathematician found, where you'll form weird saddle-shaped structures, but it doesn't occur if you randomly rotate the plates between matches.) Anyway, then you can use the plate as your indicator and build all your stone surfaces to be, well, arbitrarily flat.

  14. Re:Mortar on Pyramid Stones Were Poured, Not Quarried · · Score: 3, Informative

    I don't know that this answers your question, but people spent millenia dry-fitting stones by hammering down the high points (with other stones) and then rubbing the stones together. (People still make precision flat metal this way for machine tools. It's called way-scraping. Sorry I can't find a better link.) The point being, when they got done you had two rocks that were sufficiently flat that when put together they were within a dozen thousandths of an inch of each other -- you couldn't fit a credit card between them, and sometimes not even a piece of paper. (Common paper is pretty close to 0.002"/0.05mm thick.) So if you do *that*, then put a smidge of mortar in there and put the 2000 ton block down on top of the mortar, that might be responsible for it being only the thickness of aluminum foil. Which is a good thing: the thinner the adhesive, the better the bond, generally speaking.

  15. Re:So can someone answer something for me? on SCO Having a Hard Time In Court · · Score: 1

    Thank you: that's a great clarification.

  16. Re:It's my fault on Americans Drove Less in 2005 · · Score: 1

    I definitely lost the time I screwed up my knee and went to the hospital. The other times -- well, yeah, I got bruised, but that heals. Dents in their cars don't heal, those cost money. So I regard that as a win. They did something stupid (almost always either pulled out in front of me from a side-road to my right, or tried to pass-and-then-turn-right-directly-ahead-of-me; they were clearly at fault, so the incident cost them much more than it cost me. Sure, I'd like to take their stupidity when driving a lethal weapon out on their hides, but if I go chucking bricks through their windshields, then *I* get to talk to the police.

    Winning streak has been running since the hospitalization crash in '93, and before that, restitched part of ear back on in '83 in another pass-and-right-turn-directly-in-front-of-me, with about 15 dented and crumpled cars, with five or six broken windows, in what I'd call the 'win' column. So, maybe 15:2. (And in the ear one, the bike was repairable, and the financial cost was greater to the car owner than me. But still: that hurt like hell, so I can't call it a win.)

    Death to cars! Ride safe.

  17. Re:History of Violence on MPAA Kills California Anti-Pretexting Bill · · Score: 1

    What I was going to say, you said better.
    Beyond Borders was clearly not intended to be a blockbuster movie. As entertainment, it sucked. But three years later, I can remember parts of it with *far* better clarity than, eg. The Incredibles.

  18. So can someone answer something for me? on SCO Having a Hard Time In Court · · Score: 1

    As I read it, the judge has said that SCO can't slip new evidence in because the period to submit evidence to the court has passed, so anything they find now is not admissable for this trial.

    Does this new material give them grounds for appeal or even retrial based on new material? I assume that it'll be as nonexistent new material as all their nonexistent old material was, but how does the court system deal with this? Is there a way the judge can say that they've shown bad faith and as such it can be assumed that anything new they come up with will be just as vapory, and pre-emptively bar it?

  19. Re:It's my fault on Americans Drove Less in 2005 · · Score: 1

    >it doesn't take a nobel prize-winning physicist to know who wins the battle between an Escalade and a Schwinn.

    I guess that depends on what you mean by 'win'.
    Last time I had a head-on collision, it did total the bike. I also totalled the (cheap) car and spent some time in the hospital.
    But the last three crashes I've had, the bike suffered no damage, I had some bruises, and the cars involved had big ass dents (not (big ass) dents, but big (ass dents) because my hip and shoulder are what hits if I have a moment of warning) in side panels and in two cases broken windows. Total damage to me: some aspirin. Damage to car: in excess of $2000. I love that.

    Death to cars.

  20. Re:I definitely drive less on Americans Drove Less in 2005 · · Score: 1

    No, but vectorially speaking, the parent poster *will* have a headwind both ways unless there's an unusual wind pattern there. Canyon winds sometimes flow downstream in the morning and upstream in the evening, so if you're lucky you can get a tailwind both directions.

  21. big trucks on Americans Drove Less in 2005 · · Score: 1

    While I'm more or less sympathetic with what you're saying: I have a Subaru station wagon that gets about 30 mpg, handles beautifully on twisty icy roads, and I can put four bicycles or a spare Subaru engine block in the back. I often use it to carry 10' lumber or ladders, with the trunk lid closed. Plus, I spent another $400 and got a 4'x8' trailer, so when I need to bring home 20 sheets of 4'x8' plywood or drywall, it's no problem, and the rest of the year, I'm still getting 30 mpg.

  22. Re:What's next?? on Illinois Ban On Explicit Video Games Is Unconstitutional · · Score: 1

    But there again: one of my favorite places to stay, the Hotel Colorado in Glenwood Springs, CO, has an *enormous* version of that painting in the stairway, two stories high by about 15m wide, and nobody seems to mind boobs the size of medium-size children right out there in public -- or, I should say, the painting's been there for 70 years or so, so if people do mind they're not making much noise about it. I don't see that with any version of the David statues outside of art museums. Weird people in this country, man.

  23. anecdotal, I grant you on Apples Are For Grannies? · · Score: 1

    But literally ever grad student I know has a macbook, numbering about 15 people, in physics, biology, art criticism, comp sci, english comp, and chemistry.

  24. Re:What's next?? on Illinois Ban On Explicit Video Games Is Unconstitutional · · Score: 1

    Bad me: I was thinking about Boticelli's "Birth of Venus". I fail art class for today.

  25. Re:Why? on Ban On Louisiana Video Game Law Now Permanent · · Score: 1

    Modern American politics -- and presumably in other countries -- is at least partly predicated on the idea that politicians propose stupid laws that sound attractive to stupid people, to get elected, and then when those stupid laws are overturned on constitutional ground by the judges, the politicians are freed of any responsibility, so retain their popularity with the stupid people.