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User: tlambert

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  1. In my personal experience... on A C++ Library That Brings Legacy Fortran Codes To Supercomputers · · Score: 2

    In my personal experience...

    Most of the physics code in FORTRAN that I've dealt with are things like relativistically invariant P-P and N-P particle collision simulations in order to test models based on the simultaneous solution to 12 or more Feynman-Dyson diagrams. It's what was used to predict the energy range for the W particle, and again for the Higgs Boson, and do it rather reliably.

    The most important part of this code was reproducibility of results, so even though we were running Monte Carlo simulations of collisions, and then post-constraining the resulting pair productions by the angles and momentum division between the resulting particles, the random number stream had to be reproducible. So the major constraint here was that for a reproducible random stream of numbers, you had to start with the same algorithm and seed, and the number generation had to occur linearly - i.e. it was impossible to functionally decompose the random number stream to multiple nodes, unless you generated and stored a random number stream sufficient to generate the necessary number of conforming events to get a statistically valid sample size.

    So, it was linear there, and it was linear in several of the sets of matrix math as it was run through the diagrams to filter out pair non-conforming pair production events.

    So we had about 7 linearity choke-points, one of which could probably be worked around by pre-generating a massive number of PRNG output far in excess of what would be eventually needed, and 6 of which could not.

    The "add a bunch of PCs together and call it a supercomputer" approach to HPC only works on highly parallelizable problems, and given that we've had that particular capability for decades, the most interesting unsolved problems these days are not subject to parallel decomposition (at least not without some corresponding breakthroughs in mathematics).

    I converted a crap-load of FORTRAN code to C in order to be able to optimize it for Weitek vector processors plugged into Sun hardware, including the entire Berkeley Physics package, since that got us a better vector processor than was on the Cray and CDC hardware at Los Alamos where the code was running previously, but adding a bunch of machines together would not have improved the calculation times.

    Frankly, it seems to me that the available HPC hardware being inherently massively parallel has had a profound effect on constraining the problems we try to solve, and that there are huge, unexplored areas that are unexplored for what amounts to the equivalent of someone looking for their contact lens under the streetlight, rather than in the alley where they lost it, "because the light's better".

  2. We NEED space relics! on How Long Can the ISS Last? · · Score: 1

    Do we really need the relics of space age to hang around until they collide with something else and turn into bullets that make space even more dangerous than it already is, just so your grandchildren, if they're lucky and we haven't cluttered up the useful orbits, can have a "sense of historical understanding" like a devout christian looking at the Shroud of Turin?

    We NEED space relics!

    One "relic" I'm glad is still around is Buzz Aldrin. I still celebrate Sept. 9 every year (the anniversary of him punching Bart Sibrel).

  3. Do we seem a little too risk averse these days? on How Long Can the ISS Last? · · Score: 1

    I would assume the risk of catastrophic failure would preclude it's use as an on-site office. However, keeping it up would yield invaluable data as to what components do fail and how, as well as what parts and systems do hold up very well.

    Do we seem a little too risk averse these days? I would think that the "risk of catastrophic failure" would be enough to justify not building the damn thing in the first place, given todays risk averse climate.

    At the very least, even if a lot of it falls apart, the end of life plan should be to boost the thing to a Lagrange point, rather than deorbiting it.

  4. I think you are confused... on What Will Ubiquitous 3D Printing Do To IP Laws? · · Score: 1

    They will have no recourse, since it is the product designers and developers who own the IP. If they share it with the consumer directly, too bad manufacturer, you've become obsolete.

    I think you are confused... and so is the article... the "manufacturers" are the people who own the printers. Not to be confused with the designers, wjo come up with the designs which are manufactured by people using those printers.

    So yeah, the designers might want IP enforcement of some kind, but of course that already exists, in the form of design patents.

    But since we already have design patents available as an IP mechanism, there's really nothing that needs fixing here.

  5. Re:Contrary to the other posts in this thread... on Its Nuclear Plant Closed, Maine Town Is Full of Regret · · Score: 4, Informative

    From TFA

    But the plant faced serious allegations of safety violations and falsifying records around the time it was closed, according to the Nuclear Regulatory Commission.

    Well, yes, and I could allege you eat babies. That doesn't make it true. It would cost you a lot of money to prove otherwise, however. One of the common tactics to stall the construction of a nuclear power plant is to rely on the AEC forcing multiple redesigns during the construction process. Before anything is built at all, and then after each redesign, you demand an environmental impact statement, in case the answer is different, and there's another two years. Believe me, these groups are not averse to implementing what in Congress would be called "filibustering" in order to delay plants and increase their costs as much as possible to prevent them being built.

    Agency investigators found Maine Yankee relied on inadequate computer analyses to demonstrate the adequacy of its emergency core cooling system; “willfully provided inaccurate information” to the NRC about its ability to vent steam during an accident; and provided falsified records of safety-related equipment.

    There are enough conflicting regulations, and enough changes in regulations, that if you measured an office building built 5 years ago in California against current "earthquake ready" standards, you would find some "violations" where it would meet current code, were it to have been constructed that way last week. The important point to consider is that despite this, not one operational accident or failure as a result of these supposed issues.

  6. Re:Contrary to the other posts in this thread... on Its Nuclear Plant Closed, Maine Town Is Full of Regret · · Score: 3, Informative

    The 'backyard' for a nukulur disaster is in the hundreds of miles.

    Three Mile Island had a full core meltdown, and it basically didn't bother anyone. It seems the containment vessels contained things, just like they were designed to do. So Apparently in the TMI case, the "backyard" was limited to "inside the containment vessel". That's a "backyard" I can live with.

  7. Contrary to the other posts in this thread... on Its Nuclear Plant Closed, Maine Town Is Full of Regret · · Score: 5, Interesting

    Contrary to the other posts in this thread...

    It's doubtful that the activists who caused the closure actually live in the town; they are likely from out of area, and just uniformly against nuclear power for the sake of being against nuclear power.

    From the article, it looks like there isn't a NIMBY in town, and that the town is actually filled with PIMBY's ("Please In My Back Yard").

  8. Re:More importantly on Why Are Some Hell-Bent On Teaching Intelligent Design? · · Score: 4, Interesting

    If God did create us, how bad an engineer do you have to be to put a sewage outlet right in the middle of a recreational area?

    Assuming we were designed (a big assumption), it's a lot easier to credit engineering skill when you get a second degree burn, and you end up healing. Think about it; how would you handle a design requirement for an empty planet with no replacement parts readily available?

  9. "in the next century or so" on To Boldly Go Nowhere, For Now · · Score: 1

    "in the next century or so"

    Let me be the first to say (1) I don't want to wait, so (2) F-off.

  10. Re:Why bother at all on To Boldly Go Nowhere, For Now · · Score: 1

    Not exactly sure which planet you believe to be so much better than Earth. It may have some problems, but I'd still choose it over living on any other celestial body I'm aware of.

    It's like when you are driving and the guy in front of you is going substantially below the speed limit on the freeway: you want to be in any lane they're not in. If you change lanes, they change lanes in front of you, and you have to change lanes back to get away from their stupid.

    So your answer is "any planet the assholes are not on".

  11. Re:the taxi services have a right to be pissed on California Becomes First State In Nation To Regulate Ride-Sharing · · Score: 3, Interesting

    considering that a medallion in San Francisco can cost upwards of $200k

    http://www.sfexaminer.com/sanfrancisco/flag-might-drop-on-more-taxi-medallions/Content?oid=2193759

    -I'm just sayin'

    Only if they damn well show up when I call them, rather than taking nearby, more lucrative fares when they get flagged down on their way to me. If their dispatcher agrees on their behalf that they will show up, they need to damn well show up.

    If they don't show I, I really don't give a flying what they paid for their medallion (and most Taxi drivers in SF are contract workers, with the medallion being owned by the taxi company; the driver is just an employee with no benefits who has to follow radio orders).

  12. Re:Why is it called ride sharing? on California Becomes First State In Nation To Regulate Ride-Sharing · · Score: 3, Informative

    It's like how an SUV is called a "light truck" to get around more stringent CAFE regulations.

    Actually, no.

    According to 49 USCS 32901 [Title 49. Transportation; Subtitle VI. Motor Vehicle and Driver Programs; Part C. Information, Standards, and Requirements; Chapter 329. Automobile Fuel Economy], the term "work truck" means "a vehicle that--
    (A) is rated at between 8,500 and 10,000 pounds gross vehicle weight; and
    (B) is not a medium-duty passenger vehicle."

    So it's by weight. The Cadillac Escalade was intentionally redesigned to add 200 pounds to it to make it legally a "truck". And yes, it was to get around CAFE regulations, but it also reduces property taxes in most jurisdictions, since trucks are considered work vehicles. In addition, as a work vehicle, you can get a license plate as a commercial vehicle, which permits stopping/parking in loading zones.

  13. I have to laugh at complaining about devices... on Hulu "Kicking Back Into Action" Says CEO, Adding New Content · · Score: 1, Troll

    I have to laugh at complaining about devices...

    "The Wii UI is clunky"
    "It doesn't work with the Roku"
    "It doesn't work with the XBox"

    Has it occurred to you that it's your choice of device that's wrong? You buy a device for the content it can display; you don't subscribe to a content service because of the devices which decide whether or not to support it. It's be trivial to fix the 3 above listed issues, BUT the people who should be fixing them are the device vendors, not the content sites. Aren't you the same people who complain when Microsoft fails to support some aspect of HTML5 in IE, rather than complaining to the HTML5 web sites that they aren't supporting IE?

  14. You are wrong about the laser. on Ask Slashdot: When Is Patent License Trading Not Trolling? · · Score: 2

    Of course, the person who invented the LASER would never have been able to gat a patent with Reduction to Practice, and last I checked, the LASER was pretty damn useful.

    You are wrong about the laser. You need to read:

    The Laser Odyssey
    Theodore Maiman
    ISBN: 0970292704

    The original inventor of the laser almost lost out on his patent because he believed that there was still a "reduction to practice" requirement. The difference in the time to invention to reduction as a period of a bout 3 years.

  15. Re:So basically a revival of X-33/DC-X on DARPA Launches Military Spaceplane Project · · Score: 1

    Seems a bit redundant compared to simply reviving DC-X.

    Of course the DC-X and X-33 were prototype/technology demonstrators - with pretty much none of the capabilities that DARPA wants. They ask for Apollo, and you propose reviving Mercury. What exactly would this accomplish?

    The common wisdom is that you have to build Mercury before you can build Apollo; personally, I would have skipped the "technology demonstrator" phase and jumped right to building ships, but if you buy that philosophy, then the DARPA request is for another Mercury program before they get an Apollo program, and then the capability they want. So at the very least you skip yet another "let's almost build it than cancel it" Mercury style program.

    The X-33 fuel tank problems were never resolved, which means a new spaceplane is going to be about as viable as an X-33 demonstrator, for the same reasons, unless they resolve the storage problem.

    The DC-X demonstrator worked. The only capability that the DC-X lacks relative to their requirements is the ability to fly real real fast on a sub orbital flight to drop bombs or gather intelligence; instead you'd have to deploy other hardware or ceramic coated rebar once you got to orbit. Which is more or less OK, since it meets the unstated mission objectives.

  16. In fact, no. CDMA can be eavesdropped. on Obama Asks FCC To Make Carriers Unlock All Mobile Devices · · Score: 1

    Solution: get rid of CDMA.

    CDMA also has much better sound quality and security from eavesdropping than does GSM.

    In fact, no. CDMA can be eavesdropped.

    "CDMA (Code Division Multiple Access) is the digital telephone standard that was developed by Qualcomm and deployed by Sprint PCS and by Verizon. CDMA used RC4 encryption but the protocol doesn’t keep the keys secret, so in practice CDMA communications can be eavesdropped by a motivated attacker. In practice, though, it’s must easier to wiretap a CDMA telephone on the provider’s network. Today CDMA is used by the Sprint part of Sprint/Nextel and by Verizon."

    http://simson.net/ref/security_cellphones.htm

  17. Actually, that's an impressive vehicle. on Orbital Sciences Cargo Test Mission To ISS Launches Successfully · · Score: 1

    Actually, that's an impressive vehicle. If you look at the image gallery, the thing is very small relative to human scale for being able to get itself up to the space station. Here's hoping they can get their engine technology licensing and manufacturing issues worked out with Russia in order to keep this launch capacity beyong the remaining off-the-shelf engines currently in storage.

  18. Until 1880 this was not a problem. on Ask Slashdot: When Is Patent License Trading Not Trolling? · · Score: 4, Informative

    Until 1880 this was not a problem.

    Up until that point, there was a requirement of production of a working model, also known as a Reduction To Practice. After 1880, you could patent whatever, and get away with never having produced anything other than the speculation that your idea might be reduced to practice using some future engineering or technical ability which did not exist at the date of filing.

    One common alternative method of patent reform is to bring back this requirement, and to place the model in escrow. In the limit, this permits future study of the model, whether it be hardware, or a process patent for software. This would incidentally remove patent protection from soft processes, such as business model process patents, which people tend to find very objectionable as abuses of the patent system.

  19. Re:ZFS for Windows? on OpenZFS Project Launches, Uniting ZFS Developers · · Score: 2

    Windows isn't a very friendly development platform for Open Source, starting with the licensing requirements for tools and distribution restrictions on binaries derived from those tools when using header files containing substantial code, or runtime libraries.

    Well, the tools are free and there isn't a redistribution problem, never has been.

    Not according to this document; the runtime components are not redistributable. This is an Anti-WINE license measure:

    http://msdn.microsoft.com/en-us/library/ms235299(v=vs.90).aspx

    Now, you could argue that ZFS and Windows won't work unless MS does it because ZFS is the whole disk I/O stack rolled into one, and no driver is going to work with the kernel to allow the ZFS system to work in windows, but thats another story entirely. Theres no way to bypass the disk cache for instance, not in a way ZFS would be compatible with. ZFS must use its own cache, and directly access the raw devices, and provide the filesystem driver all rolled into one ... but spread all across the kernel, in order to get proper performance.

    Could get pretty close with some good hacks though, such as FUSE.

    This is actually reverse-engineerable. FUSE isn't an option, since pages which get memory mapped and dirtied are not propagated up via invalidation events. This is the same problem the Heidemann stacking framework has if you stack FS A on top of FS B, and then expose both of them as visible in the mount hierarchy namespace. You can do some things, but you can't do really complicated things.

  20. So basically a revival of X-33/DC-X on DARPA Launches Military Spaceplane Project · · Score: 4, Interesting

    So basically a revival of X-33/DC-X, neither of which should have been cancelled in the first place, and they're willing to pay 10X the original estimated launch costs of the most expensive one ($5,000,000 per launch vs. the X-33 estimated cost of $500,000) and 20X the least expensive one ($250,000 estimated per for the DC-X).

    Seems a bit redundant compared to simply reviving DC-X.

  21. Re:Actually on Robots Join Final Assembly Line At US Auto Plant · · Score: 1

    Doesn't help the fact that if you're laid off from a hubcap factory, you probably don't have hundreds of millions of dollars in savings waiting for a new project. No matter what industry you'd want to start up in: you're competing against rich people who can afford to buy robots and set up large factories, starting from a laid-off hubcap worker's savings (if you're lucky to have a positive net worth at all)? How the heck do you think that's gonna work? Unless you're already part of the rich investor class with loads of money to throw around, not some poor working class Joe who just lost his paycheck, you very likely aren't just going to be able to start a business --- and anything local and small scale won't have much of a market, because all your neighbors are also low-wage or unemployed thanks to robots.

    I'm going to guess the person rich off the hubcap factory is not going to compete in your taco truck business niche, which you then build into a two taco truck business, then four, then a fleet of taco trucks. Maybe at that point, you put together a very small burrito production company to centralize production costs to get a higher margin, then at some point you take the excess and establish a brick and mortar taqueria. Then you establish a couple more. Then you franchise and go national, where the startup costs are paid by the franchisee and you get a cut of their profit for use of your name, trade dress, and recipes. If you are smart, you are also their contracted supplier as part of franchising, and they buy their logo cups, napkins, fry envelopes, and frozen foodstock from you. And you build a bigger factory to supply them, and eventually factories.

    Why the hell do you need hundreds of millions of dollars to start up a hundred million dollar business? Facebook started in a dorm room; Google started in a dorm room. HP started in a garage.

    I think the problem you are complaining about is that the laid off workers in your scenario lack vision and entrepreneurial spirit. The ones in my scenario borrow money from family and friends to get a taco truck up and running.

    And if you think my example is facetious or far fetched:
    http://en.wikipedia.org/wiki/Taco_Bell

    So I would tell them to get their brains off their fat asses and start a business.

  22. Re:ZFS for Windows? on OpenZFS Project Launches, Uniting ZFS Developers · · Score: 5, Informative

    It doesn't have to be POSIX compliant to have it ported to it and it doesn't require somebody to pay for licensing. With the Features of ZFS one could argue that a port to at least Windows Server would be great and it would garnish quite a following from those who've had to put up with the way NTFS views disk volumes and storage.

    Windows isn't a very friendly development platform for Open Source, starting with the licensing requirements for tools and distribution restrictions on binaries derived from those tools when using header files containing substantial code, or runtime libraries. Part of this is an intentional legal defense against WINE and CrossOver Office, and part of it is just scale management by limiting the support community requirements to "serious developers".

    In addition, a lot of the installable filesystem and similar code, as well as a lot of the necessary VM internals (memory mapped files and paging/swapping from filesystems) are not adequately explained (i.e. they involve locking text regions with level 0 locks, which require a level 3 lock then a level 0 lock, and to do this to get the offsets on the physical media for the blocks in question. This used to not work on removable media in NT as of 4.0.1; not sure if it's supported yet, but it was the reason you couldn't install it in JAZZ drives or even regular hard drives in removable carriers.

    Having developed a filesystem for Windows95 IFSMgr, and reverse engineered all this crap, and having done it again for NT3.51, I would not look forward to having to repeat the process for Windows 7 or Windows 8, which are the only useful versions to target for by the time the code ends up functional.

    So unless someone wanted to seriously underwrite the effort (read: it's have to be done by Oracle, or by a startup who had a monetization strategy that Microsoft wouldn't preempt, like they did when my team, at a previous employer, ported UFS + Soft Updates to Windows 95, and they announced Longhorn-which-never-happened, and then put together a lawsuit about "deep reverse engineering" which would have precluded using it as a bootable FS... no thanks.

  23. Re:Color e-reader? on Insiders Say B&N Will Launch New Nook,Tablet In October · · Score: 1

    As long as the device is sold at a small profit, or at minimum not at a loss, it's worth it to sell them to increase the distributed base. If you have the device for one purpose, you might use it for another. Plus, you get to claim the sales as... sales. It gets your volume up, so you can buy components at lower prices...

    Unless it's a loss-leader for content sales for the device, or the additional sales drive costs down through economies of scale, you are WRONG: it is NOT worth it to sell them at a loss, even a small one.

    Please get back to me when you reach a junior high school reading level.

    You are neglecting what "at a small profit" implies.

    It is not worth it to go into business and break even. To do so ignores the time value of money, which is the profit you could be making on the investment capitol if you invested it in something else. This is called "opportunity cost".

    http://en.wikipedia.org/wiki/Time_value_of_money
    http://en.wikipedia.org/wiki/Opportunity_cost

    Or, to put it back in the same condescending manner you put it:

    ``Please get back to me when you reach a college freshman's level of understanding of finance and microeconomic theories.''

    In this context, "a small profit" is "an incremental amount above what I could make by having the money invested in anything else". In the B&N case, this would be things like physical books -- which is why retail flooring is an issue, and why I raised the point about amount of available physical inventory and variety of titles. I wasn't raising the issue to hear myself talk. I'm guessing you never worked in, managed, or owned a bookstore? I've done two of those.

  24. Re:Actually on Robots Join Final Assembly Line At US Auto Plant · · Score: 1

    Because in the real world barriers to entry are utterly massive (on the scale of existing companies) and productivity isn't fungible.

    If you libertarians want to actually contribute to the discussion, how about coming up with proposals to reduce the barriers or hop over them. You need to make these markets more accessible by a factor of 100 before the little guys are allowed to compete. Blaming the government *might* get you a factor of 2-5. Any ideas for covering the rest?

    I'll ignore the labeling in order to address the point.

    The fundamental assumption of the barrier to entry is that the worker would be entering into an existing market. If you are going to start a business, the only reasons to do it in the same market segment and the employer you were laid off from is stupidity or spite.

    I think the proposals to barriers to entry are already out their. If you want to open a shop in Taiwan, the entire process takes you a day. In the US, that process takes you 2-3 weeks. In India, the same process would take you (potentially) over two months, unless you bribed the proper people. So I'd place the government factor at 10x-20x, if you include establishing payroll, POS systems, and so on, as required by tax regulations. Some of it is a business line of credit for cash flow businesses, insurance for employees, union scale wages for employees, and so on.

  25. Re:Actually on Robots Join Final Assembly Line At US Auto Plant · · Score: 1

    Maybe because (a) laid off workers don't have a few hundred million dollars lying around to start up a high-tech factory (using automation to get high productivity per labor input), and (b) the market is already saturated with more widgets than a bunch of laid-off laborers can afford to buy. The people with the short end of the stick in capitalism (the working class) can't afford to start businesses when they're struggling to even keep a roof over their own head; only those already awash in money taken from the labor of others can afford to do so.

    Automation makes productivity fungible. That's kind of the point of automation.

    I don't understand why, if I'm laid of from a job in a hub-cap factory that the only business I could possibly start would have to be another hubcap factory. In other words, your points "a" and "b" assume that the laid off worker goes into competition with their former employer (out of spite for having been laid off?), rather than starting a new business and creating a new market for the product of that business.