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User: lars_stefan_axelsson

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Comments · 1,248

  1. Re:Bad Idea on Protecting Our Parents' PCs? · · Score: 2
    It's a crock of shit. I happen to have Asperger's syndrome (i.e.: "high functioning" autism), diagnosed and all, and my parents are not particularly technical. There are also plenty of completely non-technical people who have autism and related conditions,

    But the article didn't say that. It said there was a statistically significant difference. Big difference, and plenty of room for lots of "completely non-technical" to be affected.

    The idea that autistic people are statistically better with computers and technology than the general population is a myth.

    Well, it didn't say that either. It specifically said that those diagnosed with Aspbergers were usually of normal or above normal intelligence, while those being inflicted by other forms were usually on the opposite end of the spectrum.

  2. Re:Article Text (slashdotted) on A Quick Look at Longhorn Build 4053 · · Score: 1
    That's excellent, since that's the application I use the most when using Windows on my PC...

    Well, I've had to "reboot, reboot and reinstall" so many times lately, that the WinXP installer is getting to be annoying.

    Running windows the installer is one of the most used applications.

  3. Re:3 times the highest frequency being measured on Cheap PC Oscilloscopes - Any Recommendations? · · Score: 1
    Nyquists sampling theorem says that you need MORE than twice the frequency. If you have exactly two samples for one cycle of a sinewave, you can't reconstruct it. However, if you have 2.1 samples - you can.

    Actually, you need just twice the sample rate. If you have two samples for a cycle of a sine wave you can reconstruct it. Even if you happen to sample at the zero crossings. See this postingfor a crash course in what's going on. (And I do mean crash.)

  4. Re:Available in Netherlands for a long time on Qwest To Offer 'Naked DSL' · · Score: 2, Interesting
    In Holland, KPN and resellers of their local loop have offered DSL service without POTS from a long time.

    Available here in Sweden also. I now get DSL via Bredbandsbolaget, and they also provide IP telephony (via a Cisco analog to IP box).

    The best thing about the arrangement (except the cheaper phone service) is the higher sound quality of the phone, we have crappy lines where I live, and the fact that I got about 0.5 mbps more bandwidth. Since I don't have to use the extra line filter anymore the whole bandwidth of the copper pair is available to do DSL. The bandwidth reserved for telephony is used only when someone is using the phone.

  5. Re:Um, it's called x86, dude on Linus on Intel's 64 bit Extensions · · Score: 1
    If x86 is so horrible, why doesn't PowerPC totally crush the x86?

    It does. In mips per dollars, mips per transistor, mips per watt; just about any measure you'd like to apply, but raw speed. And that's just because there's no competing with the kinds of sums that Intel (and AMD) can plow into the next generation development. Like Intel stated in the early ninties: "The processor war is over, we've won. We've spent more money on development tools for the next generation chips than all the RISC manufacturers have sold chips for, combined."

    There's just no competing on absolute strength with Intel/AMD. You cannot afford to build the fab-lines they can, so even if your design is superior you won't be able to manufacture it using a competitive technology. You've lost the absolute speed crown there already.

    As an analogy, us Swedes have consistently turned out very good fighter aircraft, the latest being the JAS 39 Gripen, a modern unstable multi role fighter/bomber that's clearly superior to e.g. the F-16. And the rest of our arms development is also up there with the best. So why on earth couldn't we lick your asses or even the Russians (we haven't been to war since 1809 and are generally friendly people, so this is purely hypothetical)? Easy, we haven't got the resources. As a matter of fact we haven't even got the resources to sell the damn thing abroad since such deals aren't made on merit alone. There's no competing with the kind sweetned deal that the US can put together.

    Good designs are a dime a dozen.

  6. Re:Speaking of Volvos... on 4 Years Later, The Mozilla Tide Has Turned · · Score: 1
    My dad works at GM (I think my grandfather also did)--I still drive GM cars.

    Well, Volvo was bought by Ford so that's not an option. But SAAB is completely GM owned these days, so you really don't have any excuses. :-) Deep down you know you want a yellow 9-3 Convertible. :-)

  7. Re:Any still running? on More on IBM 75GXP Drive Fiasco · · Score: 1
    Does anyone still have one of these? I purchased two 30 gig 75GXP's - first one died after about 2 months. The second after 6.

    Yeah, I bought a 46GB one and it initially lasted well, for almost three years, but now it's been RMA:ed 3 times. I now only use it for scratch space. I'll try the firmware upgrade that was mentioned earlier. The last RMA:ed drive didn't last two months.

    I've bought three Seagate Barracuda's since, and one Western Digital. Won't touch IBM/Hitachi with a ten foot pole.

  8. Re:Farewell to the Soyuz on Russia Working on Soyuz Replacement · · Score: 2, Informative
    Dobrovolsky, Volkov and Patsaev died on descent because the outer atmospheric valve opened too early, and the cosmonauts were only wearing shirts. This had been fixed in two ways: the valve had been reworked, and everybody now must wear light spacesuits during liftoff and descent.

    Well, it was actually 'fixed' before that mission, when the crew wore space suits. The reason they didn't for that mission was that with three people on board they just couldn't fit the extra bulk of the space suits of the era. They wanted (for political reasons) to fly a three man mission and the expedient was to just cram them in regardless of the risks.

    So it was a gamble brought on by political pressure that didn't pay off. (That and the fact that the valve was badly designed. The manual shut off handle took two minutes to close the valve, but the craft bled off air at a much faster rate. It wasn't supposed to be open anyway.)

  9. Re:There is a fomerly privately owned MIG-23 in OH on Navy Jet eBayed - Some Assembly Required? · · Score: 1

    Haven't found it on the net. I saw it years ago on some Discovery show. I just did a search, but it didn't turn up much, sorry. Maybe you'll have better luck?

  10. Re:There is a fomerly privately owned MIG-23 in OH on Navy Jet eBayed - Some Assembly Required? · · Score: 1
    Duh. The tri-foil on the nose cone is warning about the radiation from the radar, not from nuclear weapons.

    No, not even really close. The symbol is there so that the deck crew could differentiate between the A-6 and the EA-6B while in the circuit. The EA-6B is a lot heavier, and hence they need to dial in the heavier weight in the arresting gear.

    This is now done by other means, so it's not been used for quite some time. However, the EA-6B crews seem to think it's a cool symbol, so I'm told you'll still see it though it's not 'regulation' these days.

    If you were in a position directly in front of the radar such that radiation would be a problem, you'd risk being sucked into the intakes anyway, so that would be your immediate worry. Not that they'll run the radar on the deck anyway, for other safety related reasons. Ever seen the video of the Sidewinder that flys of the rail being set off by the air search radar on the carrier? The missile does a 180 and comes back to hit other aircraft parked on the deck.

  11. Re:Assembly AND Military Experience Required on Navy Jet eBayed - Some Assembly Required? · · Score: 1
    In order to engage the AIM-9 it has to be sticking out in the breeze so that the IR sensor can get a lock on the target aircraft.

    I'm not arguing about the F-177 either way (though I remember the speculations about anti-awacs capability in the eighties) but while the preferred mode of operation of the Sidewinder is to acuire a lock before firing, it's not strictly neccessary. The AIM-9 (from the first version and on) will happily fly off the rail when the launch command is given and track any target that comes within it's seeker cone until it runs out of fuel.

    One of the more famous AIM-9 deployments was cobbled together to work that way. In the Falklands a British Nimrod ('AWACS') aircraft came accross it's Argentinian equivalent. None of them had fighter cover, and none of them had any ordonance, so they resorted to flying agressive circles around each other. The British woved to never let that happen again, and fitted the Nimrods with a make shift Sidewinder mount that consisted of bolting the rail to the outer portion of the wing, wiring the firing circuit to a switch in the cockpit, and using a felt tip pen to draw a circle on the cockpit glass to give the pilot an idea of the seeker field of vision, and that was it. The Nimrod of course lacked the electronics to make even rudimentary use of the seekers feedback (even the growl). Naturally they never saw another plane in the sky.

    In the old days the Sidewinder was even packed with a make shift rail in the crate, so that ground troops could fire it in an airdefence capacity. That never worked terribly well, but could be done, and offset the indignity of being bomed freighting a load of air-to-air missiles without having much to shoot back with.

    The main problem with an F-117 deployment must be the neccessity of a rail, I've never heard of a modification to the AIM-9 to allow drop firing, but if anybody knows otherwise, I'll be happy to be corrected on that point.

    P.S. And what's up with the bold quoting man, you're hurting my eyes. :-)

  12. Re:Again correct me if I'm wrong, but on Hack Your Car · · Score: 1
    Using RPMs does give you work / time, but make sure you keep your units consistant.

    Oh, no problem, we're using the SI system over here. :-)

    Yes, seriously, my friends at Volvo/SAAB who design cars really speak in 'rads' i.e. radians per second, when talking angular velocity (as it's a better engineering unit than Hertz, saves you a lot of multiplications by 2*pi), so no 'rpms'. They also use Nm and sometimes even kW for power. That last one seems the hardest to get rid of, most people will still speak of 'horsepower'. To make matters more complicated it's of course a different HP than yours; ours equal about 736W, and I seem to remember that a US HP is ca 745W. All clydesdales 'over there'? :-)

  13. Re:Again correct me if I'm wrong, but on Hack Your Car · · Score: 1
    So you're agument is that HP=Torque*RPM...I'll be more than happy to show you that the true equation is hp/lb. Or Bragging rights=C/D

    I don't really know what my 'argument' was, but it's a fact that power = torque * angular velocity. That's how physics work I'm afraid.

    Now, it you need to get a car (or motorcycle) going you need to accelerate, and as Newton realised, F=ma, i.e. a=F/m. So indeed, a lower mass will let you accelerate faster. Now, a higher force will also let you accelerate faster, and how to we get the force? By following the torque (Nm) through the gear train via the radius of the wheel to where the rubber meets the road. That's provide you with the 'fulcrum' by which to divide your torque to get your force. Substitute your own antiquated units of measurements to taste.

    All else being equal, for acceleration at a higher speed, you'll need a higher torque at a higher angular velocity, i.e. a higher max power output (i.e. HP). In reality, as wind resistance increases with the square of the speed, you'll reach a point where you won't be able to accelerate further as you won't have the force available to push you any faster (if the engine management system hasn't cut in already, or something else has limited you). So roughly, torque/weight = acceleration, max power = top speed. (Given sensible gear ratios and wheel sizes, I'm not arguing that a Caterpillar dump truck would outrun a BMW).

    There, you made me write a small book on the subject anyway.

    And regarding your motorcycle against my Volvo V70 drag race, I'm pretty confident I'll win, since I'm in Sweden, and the roads are snowed over and icy this time of year. Studded tires beat motorcycle every time, higher torque per weight or not. :-)

  14. Re:OK I'll bite on Hack Your Car · · Score: 1
    I could be mistaken, but I thought that Torque was the "response/sensation" like the car wanting to do a wheelie whereas Horsepower was the actual rubber meets the road (as in go fast).

    Well, in a word 'no', but it's a qualified 'no'. Power (HP) is just torque times rpm. It's the torque that gets you going, so for good acceleration you want high torque over as large part of the rpm curve as possible (since shifting takes time, so more gears won't really help you). That's not really possible however (if you don't go electric, they're much better in this regard) since e.g. maximum power output will put a limit somewhere near the top end of the rpm range. It'd take a book to explain this in more detail, and incidentally many good books have been written on the subject, so hit your local library (or Google).

    So if you reread your statement you'll see that there's actually some truth in it, but I'm not necessarily for the right reasons, you also have to factor in rolling resistance, aerodynamic resistance, gearing etc.

  15. Re:The tides have changed.. Positive outlook on 4 Years Later, The Mozilla Tide Has Turned · · Score: 1
    Wow, that really is rather different than the American system, where we aren't necessarily required to even take driving courses as long as we can pass the driving exam.

    Well, in fairness, the obligatory part is small, basically only the winter driving school. (Which is held in simulated conditions on a track, so it's actually great fun). You can in theory take the test without having had formal training, but they make it bloody difficult to pass if you try, so in practice most if not all, have gone to driving school.

    The downside is that we have a population of drivers that's more skilled than the average American, and take that as a reason to drive faster and with smaller safety margins. Americans are much nicer to each other in traffic. You are more like "Hey, everybody's got to get to where they are going", here it's more "Hey, I have to get where I am going!". I've driven in Boston, which is supposed to be bad by US standards, and it's peanuts to where I live in Sweden. We still have a lower death rate (about half as many as you do per capita), but OTOH you drive more, and have more urban areas. It's still a small net advantage, but not by much.

    What people fail to see is that diverting our economic energy away from needless infrastructure and into more important developments would be a net gain. Building more roads because we have too many cars, and tying up workforce in building and repairing those cars makes for jobs that don't necessarily advance the economy. We really don't export cars. It's an economic overhead--a net loss for the economy, IMHO.

    Well, my wife is an environmental science major, and I'm pretty 'green' myself, so I'm in defening agreement with you on that. But OTOH, I'm from Trollhattan; my father (and myself) used to work for SAAB until he retired, and my wife currenly works for Volvo cars. Their major markets are as you know the US, so I have mixed emotions on the subject of you guys buying fewer cars. Could we settle on you buying fewer Japaneese imports, and buying more Swedish brands instead, while lowering your total consumption? :-) :-)

    Yeah, we're off topic alright.

  16. Re:The tides have changed.. Positive outlook on 4 Years Later, The Mozilla Tide Has Turned · · Score: 2, Interesting
    Do you really mean the ignition system, as in, how the engine computer signals the ignition module, and how the ignition module triggers the ignition coils, etc...? (Or, in the case of a car with a distributor, how that whole mechanical scheme works...?) Or did you mean the ignition switch--that thingy you put your car key into, and turn to start the car?

    Speaking of the Nordic countries, he meant the ignition system. Granted it's a 'dumbed down' version that's taught in driving school (and required knowledge to pass the driving test) but you're supposed to know about the car's major technical systems, especially safety related ones. The driving examiner may ask you to do a basic safety check of the car (about the level of a US road worthiness inspection, without the exhaust check, obviously), and may test you on hypothetical scenarios on the lines of "The car starts to act like this, what do you do?"

    And if you take the test in a car with automatic transmission that becomes a requirement for your drivers license (as in your license will have the words "automatic transmission required" printed on it). As a result everyone knows how to drive 'stick'. The option of taking the test in an automatic is really there for those with handicaps, as you'd in practice be deemed not fit to drive if you were physically capable of driving a manual tranmission, but couldn't manage to learn how.

    Driving in the US is a basic right (more or less), here it's a privilege.

  17. Re:It is not the language, it is the paradigm. on Learning Computer Science via Assembly Language · · Score: 1
    They must have some pretty powerful pants, those guys.

    Well, come to think of it, shouldn't it be the other way around? If you can beat the pants of the competition, that's not much of an endorsement is it? Pants rarely put up that much of a fight.

    Then again trying to dress my 10-month old, I can almost swear that he's got his clothes somehow in on it, his pants in particular actively resisting. One such young boy shouldn't be able to put up that much of a fight on his own. :-)

  18. Re:Enjoy reading his stuff on Wolfram's New Kind of Science Now Online · · Score: 1
    By "taking classes" do you mean attending lectures or giving them? If attending, which is what I presume you mean, how does that prove expertise?

    Well, both actually, but teaching is not part of the formal requirements.

    Taking a course (what I might have erroneosly referred to as 'attending') entails passing an exam of some sort, and that 'proves' your expertise much as it did when you were an undergrad. So it's not a separate exam as part of the curriculum, it's exams as part of course work.

    In much of Europe there's required number of exams you have to pass as part of your requirements. Here in Sweden if it's an undergrad course, you have to pass with distinction.

  19. Re:Enjoy reading his stuff on Wolfram's New Kind of Science Now Online · · Score: 1
    At most of graduate programs, there is a series of written and oral qualifying examinations to demonstrate broad knowledge and expertise in the field.

    At most American graduate programs.

  20. Re:Enjoy reading his stuff on Wolfram's New Kind of Science Now Online · · Score: 3, Insightful
    The point of a PhD is original research, not taking classes.

    While that's true the way it's written, I'd say: To do research is a necessary, but not sufficient requirement. A PhD is about gaining expertise in a field of science, and advance the knowledge of that field by doing research (and publishing it, or at least have it publically scrutinised). To prove the 'expertise' part (but not necessarily atain it) you're usually required to take classes.

    Note that there's in general no way to skip the first point, by being clever. It takes work even if you're the brightest SOB to be walking around today. The world is full of smartarses of all levels of intelligence that know only of their own ideas, without as much as a clue about anybody elses, past or present.

    In my humble opinion, the first part is really the tricky part these days, with so much being published. Staying abrest of your field, so that you can correctly value the judgements of your contributions to the field (or your ideas before they become contributions) is a bit of a chore, and it's easy (too easy in fact) to miss that vital piece of information that puts your work in a whole new light (such as "that's been done before").

  21. Re:It is not the language, it is the paradigm. on Learning Computer Science via Assembly Language · · Score: 1

    :-)

    I'm more into whitespace these days though. :-)

  22. Re:It is not the language, it is the paradigm. on Learning Computer Science via Assembly Language · · Score: 1
    2a. Pure functional (Haskell/ML/Pure lambda calculus)

    Small nit (well, not so small if you're in the functional programming camp). ML (SML, O'Caml etc), are impure functional languages. I.e. they support assignement and mutable data (O'Caml is even object oriented). Haskell is about the only non-strict purely functional language around these days (though Miranda hasn't exactly died).

    If you're interested, check out O'Caml, which has a nice compiler producing code on par with 'C' for some benchmarks. Lots of good documentation (even a book) on line.

  23. Re:It is not the language, it is the paradigm. on Learning Computer Science via Assembly Language · · Score: 1
    I've written sizable programs in LISP and Prolog. I've used formal specification languages. That era is over.

    We love it when you think it is. It enables us to beat the pants of the competition. (Yes I also work for the Ericsson GSN division.)

  24. Re:Linux x86 assembly? on Learning Computer Science via Assembly Language · · Score: 1

    I learned assembly as an undergraduate at Penn State (before attending a year of grad school at Drexel), but what I got out of the course had far more to do with understanding architecture (something not relevant for most developers, but much more relevant for hardware engineers).

    I'd never thought I'd say this, as I've been into computer security and dependability for the past 7-8 years or so (and yes, am doing research into the former, and have taught assembly langage programming at university). But that's all fine and well until you factor in the performance requirements.

    With today's complex architectures and higher and higher level languages, paradoxically you need to know more about the architecture and how your high level description is distilled down to it if you are going to have a chance to reason about efficiency. It's not for nothing that modern applications spend as much as 90% of their time i chache misses.

    Now, you left a loop hole with 'most developers'. To start and argue that I'd point out that most developers are employed by major industry, i.e. they don't build a product for the end cosumer (like MS Office) but instead develop systems that will be used in house, or as part of a larger product, such as a telephone switch. I'd still say that 'most' developers need an understanding of how their code is going to do memory and speed wise. (One of my pet peeves with the otherwise excelent language Haskell, it's bloody impossible to reason about memory usage).

  25. Re:different? on Folded Newtonian Telescope · · Score: 2, Funny
    I built a six inch DOB with my daughter see photo at bottom of page

    I gotta say though; she doesn't look too happy in the picture. Maybe you should have gone for the 18 inch DOB after all? ;-)

    Seriously though, nice pictures.