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  1. Not such a big deal to write one on Developing Attractive non-GUI Apps for Unix? · · Score: 2
    About 12 years ago I wrote a set of routines in mixed QuickBasic / assembly which implemented a windowing system like this. It had routines which would automatically size and center a window for an informational message, put up the equivalent of input boxes, and even supported scroll/select/edit lists. It was recursive (window over window) despite the fact that the language I wrote it in wasn't. As I recall this all required less than 1,000 lines of code.

    The main assembly language support consisted of routines to read/write a line of video in and out of string variables, which had to be presized. Everything else was written in BASIC and ran like blazes on a 286.

  2. Wrong thought experiment on Stepping Closer To The Space Elevator · · Score: 2

    If the elevator is severed from its counterweight it will accelerate as it falls. Take a bullwhip, hold it by the handle, and spin in a circle so that the tip is "orbiting" you. Suddenly stop spinning. Let us know how tightly the whip wraps around you (analogy of impact of the cable) and whether the tip hurts when it hits you.

  3. Re:I agree with "Red Mars" on Stepping Closer To The Space Elevator · · Score: 2
    In one of the Gateway books by Fredrik Pohl, they actually have a space elevator that is blown up by terrorists (the ground station) and the loop ends up feeding into a huge man-made lake and vaporizing it

    No, the device which is destroyed in Heechee Rendezvous is a Lufstrom loop, a way of launching orbital vehicles which stores massive amounts of kinetic energy in a loop like a conveyor belt which travels at orbital velocity. Relatively small amounts of this kinetic energy are extracted by each launch (riding the loop to orbital velocity by a linear induction setup) and are restored by low-impulse continuous power sources (presumably nuclear).

    The amount of energy released in the collapse of a space elevator would vaporize a lake the length of the Equator.

  4. Re:Very neat... on Stepping Closer To The Space Elevator · · Score: 4
    If the rope were cut at the bottom, the whole assembly would be shot into space and never seen again.

    Wrong. Cut at the bottom, the whole assembly would enter Earth orbit. The question of whether parts of it would ever hit the Earth would depend on the solutions to a hell of a lot of differential equations.

    If it were cut at the top, the weight would fly out, and the rope, although no longer able to lift objects, would continue to stay aloft because it also has outward momentum.

    Wrong. Cut at the top, the rope would not have enough outward momentum to hold its own against gravity. That's why there is a counterweight.

    The only potential problem is if it were cut in the middle. Even in this case, only half of the rope would come back to earth.

    Very astute. Except...

    the only effect would be a few miles of super-strong rope falling down on whatever remote location they build this thing at.

    True if by "few" you mean about 10,000. Hint: There is no equatorial location on Earth that is not within 10,000 miles of an ocean.

    Re-read (Re? Oh well, make that just "read") the finale of Red Mars and get back to us.

  5. Re:Very neat... on Stepping Closer To The Space Elevator · · Score: 2
    I think you're a little confused... if it collapsed it could possibly strike something on the earth, or cause damage to spaceborne objects in its path, however there's nothing even close to an engineering reality at the moment that could tear the earth in two.

    OTOH you should read the end of Red Mars and imagine what the falling elevator would do when it hits an ocean. Not a pretty thought... more than enough energy there to slosh the entire Pacific and Atlantic across the continents, wiping out our entire civilization in one stroke. Makes the K-T impactor look like a popcorn kernel by comparison.

  6. They have to ask you to leave first on Big Blue's Big Blue Eyes Are Watching You · · Score: 5
    They cannot charge you for trespassing even if you enter the very same store where you were banned, much less another store in the chain somewhere else in the country, unless they first ask you to leave and you refuse.

    If they hold you and file a police report without giving you a chance to leave then they have broken several big fat laws (false police report, false arrest, civil rights violation) and it would be well worth your while to retain counsel, because you can sue their asses off.

  7. What nobody else wants (or will say)... on Open Source Programming Language Design · · Score: 5
    Truth to the hardware. Really.

    I have been involved in something close to a war with the very bright, inspired, but slightly misguided developers of firmware for a device I use every day for about 6 years. The firmware was written in C++. The day I saw it (back in '95) I said "This is the best product in our industry in more than a decade. If only it was faster." It implements a smart, well thought-out language for newbies to use to program this embedded peripheral in the environments where it will be most used. (Think truck drivers providing input.) Everything rocks except the fact that the smart, well thought-out synthetic development language can only execute about 200 instructions a second.

    OK, this is on a 20MHz 80186, but I learned on a 4MHz 8080A. I know there's a 6-level interrupt system but this is still really bad..

    Fast-forward. I have sold a *lot* of these beasties. But the competition have moved forward, and now while they still aren't as smart or well thought-out, sheer processor improvements have made one or two of them very fast. Lately I had an application that had to be very fast. I made a comment about going to the competition. This melted enought ice to cause the sea level to change. After some bantering, I suggested that I might benefit if I could download x86 machine language code as part of my pidgin programmin' language file. To my everlasting amazement the factory guys agreed and worked out a primitive API with me.

    11,000 lines of code later I have an application running on this cool little box even its makers never realized was possible. Why? It's amazing what you can do when every low-level counter isn't coded in double-precision floating point and system stuff doesn't go through two layers of indirection (C++, dontcha know).

    Abstraction can be very useful but it can also be a very short dead end. I told this company in 1995 that it was cheaper to write assembly language software than it was to replace an 80186 with an 80386; today they have done the 80386 thing and still don't have the speed I've achieved in their older instrument with better code. Sure, lots of code can be done at high abstraction with little or no loss -- but when you do all the code that way you lose a sense of what the machine is actually doing. I really don't like languages that obfuscate what is really going on to create some "virtual environment" where efficiencies are not apparent. It is very easily to get yourself into situations that look reasonable but where exponential resource requirements develop.

    The best computer languages IMNSHO are line based, not character based. They have line counts somewhat related to object code byte counts. They have a human parsing-time somewhat relatable to processor parsing-time. Sometimes this makes them harder to use than groovier languages that exploit human perception windows, but when you do learn to use them you will be able to write code that works and doesn't bog down a server farm.

    C was good at the fast thing but poor at the lines vs. characters thing. (Really, I think Dante's Devil has an extra fork sharpened up for whoever came up with the whole dumbass stream-of-characters idea.) C++ isn't good at anything except confusing people. The many other languages invented since 1985 or so are all trying very hard to be both C/C++ and the things C/C++ isn't.

    Someone mentioned what a tragedy it is that the objects in C++ have been hacked. Well, what else did you expect? OO itself is a totally cocked idea, and welding OO onto something once thought of as "portable assembly language" (ralph, ralph) is kind of like mating a monkey with an iguana. I'll admit it's a long time since I was in college but I was gabberflasted to find that an engineer who graduated in 1995 was unaware that 0.1 is an infinitely repeating "decimal" in binary floating point notation, so that 1/10*10=0.9999999 unless you round it off; and furthermore that the single-precision libraries account for this but that the double-precision libraries don't, because the doubles figure you can work out for yourself when you want to round off. It's all there in Knuth but who reads him any more when there's all this cool Java* and derivative crap running around?

    Oh well my rant for now. Karma down 3 from what, eh? It's late and I'm still dealing with this fscking stomach flu. Bah. If it can't be done in 1802 assembly is it really worth doing, I say.

  8. Not that amazing on Clear Computer Cases · · Score: 4
    Hard drives aren't hermetically sealed -- if you take one apart you will find a filter amazingly similar to the one at the end of a cigarette (and you know what gets through those, grin). The drive must contain air for the Winchester effect to lift the heads, and it's allowed to "breathe" so that if the hermetic seal were to fail humidity wouldn't become trapped inside. You would be amazed at how much water can get inside a "sealed" box as pressure changes pump the humidity-laden air in and the drier, post-condensation air out.

    The key to doing this hack successfully is to do it in a moderately clean place with little air flow to lift dust particles into the drive while it's open. Humidity doesn't matter; it's allowed to get in anyway so that it can get out when the air expands. Once you re-seal the drive you may have introduced a few particles, may even crash a few tracks. A good IDE drive will reassign these. Eventually the airflow across the platter is designed to flush this dust into the filter -- and you're right back where you started, maybe minus a few dings. Not at all the inevitable Kiss of Death you might expect.

    Now if you really want to kill the thing while it's open, light up a cig and blow smoke onto the platter while it's spinning -- death within 10 seconds, guaranteed.

  9. Re:Righter than you know on Fission in a Box · · Score: 2
    So what you're saying is, most of the energy produced by a fusion reaction go into the neutrons? I thought it was mostly gamma rays.

    Nope, it's the neutrons. There's a lot of energy output too -- thought not as much as you might think; the fusion reaction is actually a little less energetic than the fission reaction, but it scales in ways the fission reaction can't. And it makes all those damn neutrons, which aren't really what you want, but send them into a block of U238 and you get a very, very, very large boom for your buck.

  10. You do not have the slightest clue on Fission in a Box · · Score: 2
    More than 90% of the energy released in a hydrogen bomb is due to fusion.

    No it isn't. It's approximately 10% fission trigger, 10% fusion reaction, 80% induced fission in otherwise unfissionable depleted uranium thanks to the neutrons from the fusion. This is one of the most important lies that was exposed by Howard Morland when he exposed the "secret" of the H-bomb in The Progressive.

    In fact, because of the way its major fission reaction is triggered the H-bomb is dirtier than an "equivalent" mass of A-bombs. The fallout is more complex, the isotopes are more exotic, and it is just plain something you don't want to be around when it goes off. Or 1,000 miles downwind from, either.

  11. Re:Righter than you know on Fission in a Box · · Score: 2
    Would it be possible to make a mostly clean H-bomb by removing the depleted uranium? Just a thought.

    Yes, it would. It would be another animal entirely, though; the neutrons created by the fusion reaction have to do something. So when you replace the tamper in an H-bomb with something that won't fission, you get what is called a neutron bomb.

    I'm sure you've heard of them.

  12. Re:The Davy Crockett Tactical Battlefield Warhead on Fission in a Box · · Score: 2
    I'm puzzled. You claim 0.5 kiloton, they claim 0.01 kiloton in one place, 0.02-1 kiloton

    My figure comes from an interview with Ted Taylor in a photographic essay book At Work in the Fields of the Bomb which I can't seem to find right now so I can't tell you who the author was. Since Ted Taylor built the thing, I tend to think of that as a firmer figure than anything quoted in the linked site.

    It is entirely believable that the DC was scaleable, as an adjustment in the boosting would have the effect of radically changing the yield. Taylor was somewhat reticent in the interview (he was close-mouthed, for example, about the concept of levitation which is revealed in full in Richard Rhodes' Dark Sun: The Making of the Hydrogen Bomb). So there may have been this extra capability he couldn't reveal because of his security clearance, but the 500 ton figure is in the midrange of the "variable yield" figure.

  13. The Davy Crockett Tactical Battlefield Warhead on Fission in a Box · · Score: 2
    Hmmm, can't seem to find a picture of it on the Web. It weighs about 50 lb, yield 500 tons equivalent TNT, and fits in a bowling bag.

    Bombs like this need to be very heavily boosted with Tritium, which is both expensive and has a short half-life so they require relatively frequent maintenance. IIRC a guy named Ted Taylor is responsible for designing a lot of these "miniaturized" designs. They are an offshoot of the H-bomb/ICBM programs, and rely on some of the same technology as H-bombs.

  14. Re:What's new is the safety on Fission in a Box · · Score: 2
    Maybe someone who knows what the numbers really are can chip in here.

    The problem is that nearly all the byproducts of the fission reaction are themselves radioactive isotopes, with short half-lives, which means that until they decay they emit far more radioactivity than natural uranium with its 7-billion-year half life does. "Millions of times more radioactive" is in fact a pretty good description of their activity.

    These byproducts are not in themselves useful for further fission (they're the cracked halves of a U235 nucleus) but they are highly dangerous and need to be dealt with.

    Oh, let us not forget that a lot of these elements are also very chemically toxic even if they weren't radioactive. In Louisiana we call that "lagniappe."

  15. Most ignorant comment in the history of mankind on Fission in a Box · · Score: 1
    Don't worry about disposal. The nuclear material exists in nature now and we manage to live with it. There's no reason why we can't put it back with a level of safety equal to background radiation.

    The waste from nuclear reactors and reprocessing is in no way comparable to what is present in nature. It is very chemically toxic and emits far more radiation per unit time. By the same token its radiation will burn itself out in a relatively short term compared to geological radioactive sources, but it will still be worrisome to deal with for something like 100,000 years.

  16. Righter than you know on Fission in a Box · · Score: 5
    Fission power is what fuels the hydrogen bomb,

    This is for all the folks who told you fusion powers the hydrogen bomb:

    The H-bomb uses a fission trigger which supplies about 10% of its energy output. The prompt gamma rays from this blast are used to compress and trigger the secondary stage; this must occur before the mechanical blast rips the secondary apart.

    The secondary contains a stick of fission fuel surrounded by fusion fuel surrounded by a thick, depleted Uranium tamper. When the assembly is compressed the stick of fission fuel fissions, providing neutrons which...

    ...split the lithium-6 in the fusion fuel into tritium, which fuses with the deuterium in a fusion reaction which yields about 10% of the bomb's output. We are now up to 20% output.

    Finally, the incredibly huge mass of neutrons generated by the fusion reaction induce fission in the depleted Uranium tamper, yielding about 80% of the bomb's energy. Now we have an explosion. And 90% of the energy comes from fission, not fusion.

    The mantra about H-bombs being "clean" is just one of the many lies told by the nuclear industry to make itself look more useful than it really is. Richard Rhodes' books The Making of the Atomic Bomb and Dark Sun: The Making of the Hydrogen Bomb have many more details about how the current situation came about.

  17. Re:Why a TLD and not a protocol? on User-friendly Freenet · · Score: 2
    , you might as well distribute them in a way that browsers can give the correct error message ("protocol not supported" instead of "host not found").

    While I haven't used it, I suspect that freeweb does give you correct error messages. Since the proxy is running on your own machine there is no reason for it ever not to be found, thus "protocol not supported" would never come up. And once you have established connection to the proxy it can supply its own error messages by serving them up as local static webpages. (The amazing Proxomitron does this with DNS errors.)

    And the reason for doing it this way is universality. You do not have to create a different version for every browser's plugin scheme because it will work with any browser. Yeah, it's a little harder to use but it's very hard to break once you get it set up right.

  18. To refute this, and about 60 other points... on Radio Controlled Spy Plane · · Score: 1
    Stolen election? You must be joking...

    bushneverwonflorida.com

  19. Re:Point by point... on Radio Controlled Spy Plane · · Score: 2
    Then look up "LBJ" in the list of presidents...

    OK, so you have to go back 60 years. You know, I don't think things are likely to work quite the same way today as they did in the years just after Big Two.

  20. Re:Point by point... on Radio Controlled Spy Plane · · Score: 2
    The truth is we will never know FOR SURE who would have won, but it wasn't because the election was "stolen," it was because many parts of Florida used incredibly outdated voting equipment.

    Yeah, outdated voting equipment is what set up those police checkpoints near polling places frequented by blacks. And I guess it's those outdated polling machines that illegally removed tens of thousands of "felons" from the voting rolls -- again, predominately black "felons" -- who had never even been convicted of crimes. (And it's a total coincidence that that database was set up by a company which is also a big republican contributor.) And of course those outdated voting machines just forced the design of the butterfly ballot which gave us Pat Buchanan's startling performance in a county where you'd normally expect him to get about 7 votes.

    It isn't just about the recount. The Dems thought the recount would put it over the top, which it didn't (quite), but there are more than enough other irregularities for which there is no legal recourse to make it obvious that the will of the people was thwarted.

    And the Repubs weren't planning to play nice if the count went against them. I know some folks in the local political machine (they ran the smear campaign against Mary Landrieu when she beat Woody Jenkins out for the Senate by a few hundred votes). Calls were going out all night in preparation for a mass call for recounts, protests, and general dirty tricks. Then the count went in their favor and it all wound quietly down. (Well, mostly quietly. There was that little riot at the recount office, no doubt caused by the outdated voting equipment.)

    Yep, we're gonna call the Vile Pretender "Resident" until we get the chance to kick him out in 2004. Get used to hearing it.

  21. Re:Slashdot 101: NOBODY modded it up on Review: The Dish · · Score: 2
    maybe you shouldn't abuse the bonus.

    It's my bonus and I'll do with it whatever I damn well please. I don't play the game of posting under another account to "preserve my precious karma." FYI the system doesn't care if your karma is 43 or 50. There is plenty of room before the bonus is really in jeopardy, unless you really are a dedicated troll.

    I don't really take it personally when I get modded down, but it does annoy me when it's obviously due to ignorance on the part of the moderator. Really, that's worse than being modded down for disagreement IMO. Learn how the system works before sticking your fingers in its moving parts. Your fingers will thank you.

  22. HTTP proxy on User-friendly Freenet · · Score: 2

    Because the domain proxy is a proxy it will work with any browser at all. It will even work under Linux with Wine. The browser does not have to "support" anything except the standard redirection of HTTP port 80. Thus it is not browser-dependent or version-dependent.

  23. They did this... on Review: The Dish · · Score: 2

    ...for still pictures, many of which were taken with 2 1/4 inch format film cameras. But in 1969 videotape required both a huge machine and huge amounts of tape, for which there was no room on the mission. In fact, it was still pretty standard at that time for TV series to be distributed on 35mm photographic film, to be projected into a video camera for broadcast. The equipment was smaller and cheaper; the only perceived disadvantage was that you had to develop the film, and it was one-use. Needless to say, there was no room for a 35mm film movie camera on the lander either.

  24. Slashdot 101: NOBODY modded it up on Review: The Dish · · Score: 1

    ...because as you would know if you had read the FAQ, slashdot users with enough karma post at +2. I wish more moderators were aware of this because several times I've had my karma spiked because some butthead thought he was correcting another moderator's "mistake."

  25. Re:Point by point... on Radio Controlled Spy Plane · · Score: 2
    You're assuming he'll win his party's nomination again. Bush will not be the President in 4 years but there will be a Republican in the office.

    That would be pretty unprecedented. Offhand I can't think of an instance where a sitting first-term president didn't get his party's nomination to run again. While he is working hard to piss off enough people to accomplish this, I still think dubya would have to fuck up spectacularly to lose the 2004 nomination. The election is another matter -- I don't think he'd win if he had to run again right now, much less after four more years.

    OTOH in all likelihood whoever the Dems put up is gonna be just as bad -- pro free-trade, anti free-speech, pro-censorship, pro-anything-big-industry-wants (DMCA anybody?), and generally indistinguishable from either dubya or billC in the areas that matter to us. So you could say we'll have a republican wolf in democratic sheep's clothing, like we did for the last 8 years.