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  1. Re:OS 10 crash on Serious CGI Bug in MacOS X Servers · · Score: 1

    Sorry, but no process however badly written should be able to kill a system so bad it needs to be power-cycled. Yes, a runaway process might consume too many resources and slow the thing to a crawl, but it should still be possible to reboot it!

    I've encountered times when runaway processes made the system so slow that it becomes almost necessary to reset the system. Stuff like a program spawning children while in a busy loop or something like that can make the system slow down so much that it becomes unresponsive.

  2. Re:MD5 salt? on Ask Slashdot: Securing Web Servers Against Cracking · · Score: 1

    Does the system us a salt value with the MD5 passwords? If not, why not? If they don't, one would be able to make a dictionary of encrypted passwords and do bulk checks against it.

    The description of the md5 format is in the gnu info page for glibc. Basically the password format is listed as $xxxxx$yyyyy where the x's are the salt(I think its 8 chars long) and the y's are the hashed password. The info page suggests randomly getting a salt using something like /dev/random

  3. Re:Assumptions on Leech Neuron Computers · · Score: 2

    By the same token why not have the "brain" separate from the "body"? The "body" would have a sort of pre-processor that would decide what to send to the main "brain". This would act sort of like an autonomous nervous system to handle "reflexes" and similar things that couldn't handle the latency of remote communication.

    There are a lot of advantages in having the brain attached to the body. If the brain was in a separate location, you would have to worry about communications between the two. What happens when the communications link between the two gets broken for some reason or another? If the brain were connected to the body this is not a problem.

  4. Re:A whole new can of worms... err... leeches on Leech Neuron Computers · · Score: 1

    They are opening up a whole new can of worms with this one. It starts out small and innocent. It will be interesting to see what the outcome of it all is. Anyone remember that movie "The Matrix"? Yeah, that's right. At the turn of the century the people of the world rejoiced as they celebrated the birth of the AI. And what happened next?

    Well considering that they barely got the computer to add and are now trying to get it to multiply, it'll be a while before we have to start worrying about these computers taking over the world.

  5. Re:Ethical questions? on Leech Neuron Computers · · Score: 1
    They use Leech neurons because they've been more extensivley studied than most other types of animal neurons, probably because Leeches don't have a whole lot of them...

    Actually its probably because leeches are cheap and easy to get. It would be an advantage to have more neurons because that way you could do more experiments with just one animal.

    Aside from that the leech neurons are probably pretty close to neurons in order animals since otherwise they probably wouldn't be studied that well. Not many people are interested in studying leech neurons just to find more information about leech neurons. However if you could extrapolate this information to neurons in other animals (including humans) ...

  6. Re:Checklist on Ask Slashdot: Securing Web Servers Against Cracking · · Score: 2

    * MD5 crypted passwords. Don't know if this is supported on RH, but Debian 2.0 or better does. This is a wonderful feature, it's settable in /etc/login.defs. It allows passwords longer than 8 characters (standard shadow limit), and to the best of my knowledge there are no password crackers which will crack MD5 hashed *NIX passwords. There's also lots of other fun stuff to mess with in login.defs, btw.

    Crack 5 does MD5 encrypted passwords and it came out in 96 so its been out there for a while. Actually, for crack you need to follow the instructions for free/open bsd md5 passwd files, but other than that it runs perfectly well. In this respect I think the *BSD camps do have better security features since they seem to have had a lot of the security stuff linux is adding now for a while.

  7. Re:Yuk on Massive Bandwidth over Powergrids? · · Score: 1

    All this is exactly my point. If we would spend the money to research solar, we would come up with better efficiency, enough to make it viable outside of "hot" places.

    Efficieny doesn't matter if you're getting more cloudy days than sun days. Even assuming this isn't a problem, I can think of several instances where a power grid is necessary. For example, take a 20 story condo, I'm pretty sure the building is using up more energy than can be produced by solar panels covering the roof of the building.

  8. Terraforming probably will not work on Mars 3D- and you don't need the glasses · · Score: 1
    yes we can terraform mars, first introduce plants so they will produce oxygen and absorb co2, then an atmospher will be created, then...

    Unfortunately I believe Mars has too little mass to mantain an atmosphere of the necessary density. I think that the current theory is that mars had a atmosphere but a lot of the ligther molecules flew off into space since the gravity was not strong enough to hold them in the atmosphere. I think a similar problem will occur if we pump new N2, and O2 into the atmosphere.

    Even if we are able mantain the atmosphere with continual infusions, the loss of the molecules will represent a continual drain on the planet's resources. This will probably require continual resupply to the planet.

    It'll probably be better in the long run to create enclosed environments for habitation, preferably underground so that the radiation exposure is lower.

  9. Re:What about here gametes? on Cloned sheep shows signs of premature aging · · Score: 1
    Interesting point. But wouldn't it just be like having offspring when one is older in life. If someone sired offspring when they were 70 would their offspring have an older "genetic age"? I don't think so. The only problem that I can see is that Dolly may reach an age where she is too old to have offspring- three years earlier!

    At least for egg this isn't the case. The eggs are produced during fetal development and meiosis is halted just before the first division. They stay this way until ovulation when the cells divide and ovulate. That's why older women have a greater chance of birth defects, their eggs have been around longer and have a greater chance of being damaged.

    For sperm, I'm not sure what the development is like, but I suspect that it involves some type of way to prevent/reverse the degradation of the telomeres.

  10. Dictionary Computer on Australia Admits to sigint · · Score: 1

    The question is how much processing capabilities do those dictionary computers have? Those stations have to be capturing terabytes of data every day and I'm not sure how well the computers can process the data.

    Then again a big farm like at Fermi can handle quite a lot of data, so it's not inconceivable that they get enough processing power from their computers to handle it all. However they have to get quite a lot of data so they probably can only search for selected things rather than just go "fishing" for terms like CIA. nuclear bomb, etc.

  11. Re:So, according to the article, we're still guess on Age of Universe Derived · · Score: 1

    he emphasis is mine. Is it the media or the scientists that make these proclamations seem so cut and dried, like, "whew! now that's settled!" when in fact, there is so much guesswork, any conclusion is just not certain? I think it's the scientists, but they should know better.

    I think a lot of the emphasis is due to the media. I think a lot of scientists realize that these are just one of several data points out there and will admit that.

  12. Not an accelerator on Students Build Reactor For Scavenger Hunt · · Score: 1

    My guess is that the dumb shit reporter couldn't tell the difference between an accelerator and a reactor. You *can* produce plutonium with an accelerater, just not very much. During the Manhattan project this approach was examined but it just wasn't capable of producing the volume of fissionable material needed for a bomb.

    The thing was not an accelerator. I was there and talked to Fred and Justin about it. First of all, there was no power going into the shed they had it in, an accelerator requires alot of power to run plus there were no magnets around.

  13. Re:What amount of Plutonium is Safe? on Students Build Reactor For Scavenger Hunt · · Score: 2

    hus the production was probably theoretical, and not actually tested for (although if theory says its there, you're pretty safe in assuming it is there). With the plutonium confined to the interior of the sample, you're not going to ingest it.

    Actually the were able to conform decay from the uranium atoms that they predicted were produced. So given the physics involved, there was no reason to assume the plutonium atoms were not being produced. Of course they only had about 8000 atoms of uranium so they couldn't have more about a few thousand plutonium atoms. You would get more radiation from a particle shower coming off of a cosmic ray hitting the atmosphere so it is relatively safe.

  14. Re:Will the Gov ban it? on Students Build Reactor For Scavenger Hunt · · Score: 4

    Lessee... kids got instructions on how to make bombs on the Internet... kids make bombs... kids kill a bunch of people... Government bans said instructions from the 'net. College students learn how to make plutonium in school... college students make a working nuclear reactor, in a day, from scratch... will government ban that from schools?

    Look it wasn't a working breeder reactor. It took Thorium to Uranium and then to plutonium. It took Justin and Fred(the guys who built it) about 2 days to build it. However they started with 4 grams of thorium(alpha source) and got about 8000 atoms of uranium(neutron source) after a day and about 100 atoms of plutonium. Plus it took more energy to sustain the reaction then it producded. All in all, it wasn't a viable way of producing large quantities of uranium or plutonium since you have to separate a very messy mixture.

  15. Re:Honorary Doctorate on Linus To Recieve Honorary Doctorate · · Score: 1

    I guess I'm lucky to be at a unversity which has never given an honorary degree out. We also have a tradition of having the commencement address given by faculty only. Clinton asked to speak at this year's commencement and there was a big debate about whether we should have refused. In consolation, I believe that he's not going to be listed as the official commencement speaker, that honor goes to a Bio prof, Elaine Fuchs. And he's definitely not going to get a degree, the administration response was that we only give degrees for academic work of the highest caliber.

  16. Re:Sounds like a match made in heaven on Chain Letter on AOL fools TV station · · Score: 1

    Unfortunately AOL doesn't endear themselves to the technically inclined when they repeatedly run a commercial where the actor says:
    "Why would I need America Online? I've already got a computer!"
    Which is analogous to the statement: "Why would I need a road? I've already got a car!"


    The two statements are not analogous. A computer can be used quite productively without AOL or even an internet connection. It may be hard to imagine but people get along just fine without one. A car doesn't really have much of a purpose without roads to drive it on.

  17. Re:Chess on Task Processor Found in Human Brain · · Score: 2

    Admit it, the human brain is not all that good when thinking purely mathamathically. Computers are.(for now anyways)

    I disagree entirely. Numerically computers may be bettter but mathematically no. Computers aren't very good at proving theorems and coming up with new ones(the theorem provers out their really aren't that great despite a few interesting successes). Mathematics consists mostly of proving theorems and coming up with new ones. Thats what math people have been doing for the last 200+ years. Frankly from my experience with my math profs, I wouldn't trust them to multiply two reasonably large numbers without making a mistake.

  18. Re:Humans already are programmed =) on Task Processor Found in Human Brain · · Score: 1
    Look at commercials, advertisements, and marketing as functions of programming a person. Look at movies as ways in which to program a person to act, behave, and believe. Saturday morning cartoons program kids in what is 'right', 'wrong', and 'okay', and our politicians, our news agencies, our TV, they all program us towards what is socially acceptable and unacceptable.

    I'm not too sure how much these things really affect us. Sure they have some influence but not the influence that you seem to attribute to them. These techniques seem more like nudging the mind in certain directions, they don't work all the time and they can't change the mind significantly.

    However you have to agree that we don't have the ability to compel people to carry out complex tasks in a way we tell them to. I believe this is the sense the original poster used it in.

    Actually alot of this seems to be a semantic problem. We use the word program in at least two different senses(cs, general usuage) without distinguishing between the two. Ills such as racism, sexism, ageism, etc, can all be traced to unwanted side effects of social programming, unless of course you believe those are fundamentally built into the human psyche.

    I'm not sure that these problems are the result of social programming. People seem to have a inborn need to classify objects in the world around them in order to predict and understand the world around them. We put all objects that resemble each other in a certain category so that we can use our experience with one object in the category to explain other objects in the category will work. Although the way people classify each other seem to be social(race, class, etc.) it seems to happen universally. So, I think that this is probably a result of our need to classify.

  19. Re:Megahertz and cache... on Task Processor Found in Human Brain · · Score: 1
    I don't think that's a good way to look at it when you don't even know how the 'pictures' are stored.
    Wagenaar did a study on long-term memory: his conclusion was that there are a lot of things you forget: even the events that are (were?) important to you.


    I know that models of how long term memory work are currently lacking. I believe the current models(aplasia and mammalian hippocampus model) predict long term memories of about a few hours based on the phosophorylation of receptor gated channels.

    I agree that the mind probably manufactures a lot of the detail we seem to remember(I'm not sure whether this applies to those who have "photographic memory" since I'm not sure what having such a memory entails). I remember reading about psychological studies where people recalled an event from their childhood with a lot of detail despite the fact that it never happened. As I pointed out, using a computer model to explain the brain's function is not necessarily a good thing. I would definitely hesistate to say that the brain has X +/- Y bytes of storage. I was just trying to show the poster that the brain has quite a lot of storage(certainly more than the equivalent of 2 MB).

  20. Re:Megahertz and cache... on Task Processor Found in Human Brain · · Score: 2
    nteresting. If the brain does indeed have its own CPU, what speed does it run at? And how much cache?

    The short term memory of most people is about 7 things(numbers, names, etc.). The long term memory is open to debate but is pretty considerable. Consider how much bytes storing something like a picture takes and multiply that with all the memorable images we have in our minds.

    Speed wise, signals travel along neurons at about 30 m/s. People have estimated that the depth of a typical path has to be a 100 neurons or less to get a reaction time of about half a second to a second that is necessary to carry out a conversation. However a typical neuron is connected to several tens or hundreds of thousands of other neurons so the brain is massively parallel.

    All this assumes that the brain functions in a similar fashion to computers which is not necessarily a good assumption to make.

  21. Re:Most powerful brain additive on Task Processor Found in Human Brain · · Score: 3
    This does scare me a bit, however. After all, if the brain is a computer, that means it can be programmed. And if it can be programmed, you know a virus can be written. Or worse, Billy will decide to port Windows to the brain.

    Whether the brain is a computer is still a subject of considerable debate. The researchers seem to have located the region of the brain that allows people to jump back and forth between tasks. However, this does not mean that the brain handles this in the same way that computers do.

    Even if the brain were to operate like neural networks (the cs/math versions not the bio ones) do, the possibility of programming it would be in doubt. Currently no one really understands how a trained neural network operates or how to actually program it directly aside from randomly assigning the connections a weight and then training it. And this is for relatively simple neural networks with maybe 5 layers, the brain is considerable more complex. It'll be a while before we fully understand it, let alone be able to consider programming it. We don't even know how long term memory is kept/created and the only models around only explain memories that last for a few hours.

  22. whoa, who's acting threatened? on Students Opting Away from high-tech Degrees? · · Score: 1

    Okay, name me somebody at your company with a PhD who still codes worth a flip. Yes they exist and are good; I've just never seen one in any place I've worked.

    Just one sample does not give an adequate basis for generalization. A lot of Ph.D.s have written alot of good code. Just for example, Linus, Knuth, Ricthie,Kerningham, etc., etc. The better universities require solid scholarship and research to get a Ph.D. and in alot of cases this requires things like implementing an compiler, software to do robotics work, vision research, etc. However if the Ph.D. was in something like algorithims in finite groups then I could see that person not being a good programmer.

  23. Screenshots don't do this game justice. on Mac Q3Test Shots · · Score: 1

    All in all, I was very impressed with how well the engine performed on my system (B&W G3/300, 16MB Rage128, 64 MB RAM) even with virtual memory on. Q3Test requires 70MB of RAM and I only have 64MB real memory

    Is there anyone else that thinks there is something wrong when a game demo requires 70MB of RAM? Is the code that complex or is it really that bloated?

  24. How much space? Format? on Bootleg Movies for Download · · Score: 1

    So how much space does that require? What format is prevelant for movie downloads?

    The version of the matrix that I watched was a mpeg file. It was about 1.4GB. Someone I knew was sharing it using windows sharing and I was able to watch it over the network. The quality was pretty good except for it was a little dark. There was no music however as the article said. It was definitely not something that someone captured using a camcorder since the movie filled the entire window and there wasn't any border or anything like that around it. I think that it was probably captured off a digital copy since there was a small white Z in the upper left corner and about half way through the movie someone fiddled around with the sound settings and sent all the sound to the left channel and then the right channel before restoring it to normal stereo mode.

  25. HOWTO Bust Script Kiddies? on Script Kiddy HOWTO · · Score: 1

    reinstall? sheesh, the only reason he got in was because you forgot to do the security upgrades.. now you're reinstalling the os without any security upgrades?

    Actually it's probably the best course of action since you don't know which files were replaced/added with backdoors, especially if you don't run something like tripwire. I believe the procedure is to reinstall and immediately apply all the security patches then bring the server back online after restoring data and securing.