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User: ebuck

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  1. Re:So Tempting... on JSP and Tag Libraries for Web Development · · Score: 1

    Dear sir,

    Due to hostile conditions at my current work place, and probing inquiries by the w3c concerning our HTML tagging, we are unable to discreetly move a large number of web pages to a remote server co-located in eastern Tenessee.

    This represents an opportunity for yourself as these web pages are desperately needed by private developers of our internal web site who are having difficulty without their Frontpage web instruction....

    I couldn't finish, it started to sound too true.

  2. Re:PHP and Java on JSP and Tag Libraries for Web Development · · Score: 4, Insightful

    This boggles my mind... I am trying to recover from the pain.

    PHP is seldom used in an environment where there is any kind of MVC, and is often used where the logic is built directly into the web page. Java servlets can be coded to do the same, but it's an ugly, hard to maintain practice which shows the lack of design most web pages have these days. A combination (while possible) would probably bring out the worst in "slap your page together" design.

    Now a few books on how to draft your page in PHP, and the refactor them into MVC structured JAVA would be divine.

  3. Your control shouldn't generate the view anyway. on JSP and Tag Libraries for Web Development · · Score: 1

    Anyone performing this kind of development forgot a key aspect of designing their servlet/JSP. MVC gets bandied about again and again as the thing to do, but most of the servlets I've seen have nothing to do with MVC.

    If you want real MVC, your servlet which receives the request would be considered the Control (C) as such, it shouldn't have any System.out.println(...) requests in it at all. That would be part of the View (V).

    A much better solution is to write 3 modules for each web page you are presenting. One for the receiving servlet (C) which then manipulates the Model (M) appropriately, and redirects the requests to the appropriate JSP (V) with additional information in the form of JAVA Beans.

    Now you have real MVC! Your model doesn't have to control your interface, and your view cannot request data your Control servlet didn't pass along the redirect. It's many more modules to write, but each one is smaller and much easier to maintain.

  4. Re:So when you walk into a store... on RFID Industry Confidential Memos · · Score: 3, Insightful

    Why are these posts even considered interesting / insightful?

    As broken as the DMCA is, it only discusses circumventing controled access to copyrighted works. Last time I checked you couldn't really copyright a bottle of laundry detergent. And another thing, the RFID tag couldn't possibly provide controlled access to anything it was attached to, it's embedded into the item, not surrounding it, so there's nothing to circumvent.

    Destroying the tags would be a simple case of property rights. If you own it, you can destroy it, and although I would expect a bit of "you didn't really buy the tag, but you are leasing it forever" slipperyness here, that won't hold up in the courts for long.

    Seems like the new "a Beowulf cluster of these" tagline is becoming "would be illegal under the DMCA"

  5. Not a bad idea until on Solar Sailing and Physics · · Score: 1

    Not a bad idea until you run out of gas.

    Actually, since you are in space, you don't really even have to heat the gas. Just open your (relative to space) pressurized bottle of gas, and you have an instant rocket. Problem is, it's very expensive to haul up a bunch of atoms up through the atmosphere for the sole purpose of throwing them away in space. And help you should you run out, as you would no longer have any propulsion system.

  6. Re:Well, IANAP on Solar Sailing and Physics · · Score: 1

    Who said that a poton doesn't loose energy after bouncing off of something? Perhaps it doesn't lose speed (c is a constant) but it could actually lose a bit of it's mass (mass and energy being covertable). Eventually it might just absorb into a panel.

    Also who is designing these mirrors? Forget the perfectly reflective bit, and notice that there is no mirror which can both:

    a) take a sphere of light and convert it to all parallel rays.
    b) take a bunch of parallel rays and bounce it back as parallel rays.

    To do the first, you would use a parabola, to do the second, you would use a plane. Plus parabolas only transmit light in one direction, and this experiment needs parallel light bouncing back and forth in both directions. Getting a significant amount of light "in the groove" would require reflectors which would need to be perfectly transparent to light already in the path, and at least partially refractive to light entering the path. You can't have it both ways.

    But it's still a neat thought experiment.

  7. Re:Actally no - different mechanisim there on Solar Sailing and Physics · · Score: 1

    Of course the air has to move around the edges of the foil to have the thing rotate, but your post raised a question in my mind.

    Why would air seek out a high temperature clime? After all if the dark side of the vane is hot, it should radiate a bit of heat to the air directly contacting it, making the air on that side of the vane just a bit hotter. I would expect a corresponding increase in air pressure (on a microscopic scale) which would push the air (and vane) away.

    This is not a troll, or a challenge, I really would like to consider other possible explanations, as many provided explanations for everyday things are often, suprisingly wrong.

  8. Re:Photon Pressure on Solar Sailing and Physics · · Score: 1

    Mabye you are referring to heat?

    The potons leaving a star can hardly be keeping the star's surface aloft, since the momentum would imply a pressure forcing down the star's surface.

    Stars supernova, when the fusion reactions change character, that is, when they start fusing heavier elements together poducing less heat. Eventually the crust of the star will fall into it's center creating a short but violent burst of pressure, and one last big fusion reaction.

    My knowledge in this matter is a bit rusty, and new theories may have been developed, but I cannot imagine that the photons push the crust up, because photons have mass which implies leaving photons push the crust down (with respect to the star)

  9. Re:Solar wind and Voyager on Solar Sailing and Physics · · Score: 0, Interesting

    No, Voyager and other craft to this date took advantage of gravitational alignment of planets, but used no solar sails to capture solar "wind".

    I am not sure about Galileo's design, but as my dad worked on Voyager, I still have a bunch of it's design specs around.

    Voyager uses and ion drive to manuver, which is powered by radioisotope thermoelectric generators, which in turn are fueled by our friend plutonium 238. The ion drives are nothing like the "star trek" version, rather they are pointed wires which provide propulsion by throwing electrons off of its end.

    Interestingly enough, the main problems with Voyager today tend to be that the radioisotope has degraded till less energy is available, the wear and tear on the couplings reduce the amount of electricity available to various components, and the extremely low temperatures require a lot of heat from the powerplant to bring them up to operating temperature.

    As a result, nearly all of the Voyager subsystems have been shutdown, excepting those critical for operation.

  10. Re:The article is wrong on Solar Sailing and Physics · · Score: 1

    Although I to am sorry to see so many errors in a printed article, it is possible to return to the same state.

    Of course, it wouldn't be a Carnot cycle, since heat would not be involved (at least not to an important degree). But by retracting and extending the sails on a craft designed to do so, you could eventually (theoritically) find an equilibrium, or a gravatational path back to your origin.

    Problem is, you will still need a second source of energy. Assuming you manage to select your desired distance from the sun, you would have no control of where along the orbit you wished to be, or if using the orbital motion to assist in your radial equilibrium, you would have no choice in which orbit you could select.

    Using other planets is impratical, as it's unlikely you can place them exactly where you want them whenever you wish ;)

  11. Re:Woohoo solar sailing on Solar Sailing and Physics · · Score: 1

    Better pack your sun-screen.

    All I've got is SPF 7x10^8, anyone have 9x10^15?

  12. Re:Laws? Who needs them? on Solar Sailing and Physics · · Score: 1

    Cool concepts like the solar sail come from the theoretical extension of our current understanding of physics. (ie. they are nifty ideas that should work)

    Cool concepts that come from violating the known understaning of physics, are still cool concepts. But they won't work.

    I won't knock the "coolness" of something equivalent to a perpetual motion machine, but I know I will never see one. (excepting that all of the people observing nature for the last 200+ years were wrong).

    Coolness should not be a criterion for launching anything, except mabye a re-enactment of the dot-bomb craze.

  13. Re:Well, IANAP on Solar Sailing and Physics · · Score: 1

    Ok, to be kind (for all the non-physicists out there).

    Light is both a particle and a wave. It really depends on how you observe the light in your experiment. If you look for waves, you see waves. If you look for particles, you see particles. Light waves have all the propertys of energy, and light particles have all the propertys of matter.

    The implication here is that light is something which we can only see as a particle or a wave because of how we look at it. Waves and particles are more interrelated that we previously thought (previous = 80 years ago), and a better analogy (than the one you might already hold) is that they are two visible sides of a coin we really cannot see.

    I know I am not a physics teacher, but at least I was a good student. Cheers!

  14. Actally no - different mechanisim there on Solar Sailing and Physics · · Score: 4, Informative

    The black vanes on the spinning apparatus absorb light more efficently than the white ones.

    This absorption of energy causes the black side of the vane to be hotter (by a very small amount, i'm sure) than the white side.

    The heat radiating off of the dark side of the vanes works much in the same manner as a jet engine (without the need for a compression chamber). Note that the reason it's in a glass bulb is to impose a partial vacuum is to reduce air friction which would keep the vanes from moving. Also the use of a needle point piviot further reduces the friction.

    So, in a word no. The solar sail intends to gather energy by photons bouncing off of a sheet, while your example is really just a simple heat engine.

    You can verify this independantly with a little obseration and thought. After all wouldn't the white side of the vanes be providing the thrust if the energy was harnessed from potons bouncing off of it?

  15. Re:Ig Nobel candidate on Intellivision Operating System Revealed · · Score: 1

    Although I get a chuckle at the suggestion...

    It seems this project would be disqualified since it can be reproduced (and should!)

  16. Re:I still don't get the allure of Java on Industry Leaders Discuss Java Status Quo · · Score: 2, Interesting

    The "allure" of JAVA really has very little to do with JAVA itself.

    A big part of the "allure" of JAVA has to do with the history of your average programmer.

    The typical programmer used to go to collage where they learned C / FORTRAN / COBOL or if they were lucky, mabye PASCAL. Then they went into industry where they solved a problem, wrote an app, and all was well. That is, until the bugs came rolling in. Somewhere between fixing the bugs, including new features, interfacing with the new library x.so (or x.dll) techniques to deal with code complexity were cobbled together. Some were better than others, and those currently stand as best pratices.

    JAVA is revolutionary (and has allure) because for once, a commonly used language offered a new paradigm (object oriented programming) and enforced (no backwards compatibility) all of the "rules". This means that in JAVA I really do feel comfortable not paying attention to the guts of class X because I know that class X cannot mess up my bit of code unless I allow it to do so.

    My only gripe with C++ is not that it cannot do what JAVA has done, it is that it allows the rules to be broken via backwards compatibility with C. So to have the same level of confidence modifying a C++ program as I have in JAVA, I need to read the whole thing to make sure it is Object Oriented (TM) and not just touched up C.

  17. Realized opportunities - Poor References on Industry Leaders Discuss Java Status Quo · · Score: 1

    When JAVA was first announced, it was to be the language for everything.

    Cell Phones: Motorola, Samsung, Mitsubishi and many others http://www.microjava.com/devices

    Appliances: Advanced PDAs / Set-top boxes, and others, but then again, appliances haven't really lived up to their hype either.

    Games: Most of the yahoo games are JAVA and other exist (if you look for them)

    Databases: hsqldb a fully (100%) relational database written in (you guessed it) JAVA.

    Web Access: JSP / Servlets are common (even if they don't proudly display their .jsp extension) and there's even a java applets offering terminal / telnet / ssh.

    So I think all of this has come to pass. What SUN marketed was a revolution in the industry. Well, your revolution may be my garbage pickup, but I can't believe that every general programming language should be drafted with the aid of a clear marketing / focus study.

  18. Re:You can make a portable C++ app. on Industry Leaders Discuss Java Status Quo · · Score: 1

    I agree, but it's not nearly as portable as you imply.

    To get the level of portability that JAVA presents straight out of the box, you either have to...

    1. Create or use a framework to generalize all of the variant parts on each of your target platforms.

    2. Make sure that the same collections framework is available for all the above said platforms, or be prepared to write (and debug) your own collection framework.

    3. Make sure that the compilers on all of the target platforms have options which result in like functioning code (easy) which performs similarly on the different platforms (hard). If the performance isn't similar, then you'll eventually optimize youself into Hell with #ifdef OS_XXX.

    In the end you'll find that only in the best of circumstances and with a great amount of foresight will a typical project manage to produce portable C++ code. Even then, odds are the portability will come at the cost of readability.

    If you really want a portable C++ app, don't try to wrap the variant bits yourself, save your coding time and look to a project like wxWindows (or any other with similar goals) as they all have been trying to crack this nut for a long, long time.

  19. About Xerox on Industry Leaders Discuss Java Status Quo · · Score: 1

    Sorry to call your (obovious) bluff, but Xerox has contributed scores of insight and work in creating the 2D API. And if you have ever had to really get into the guts of rendering to screen, you could ask for a better API, but I doubt you will get it.

    Your deep experience may be dated. It may be fresh. But if you were designing grids when JTable was unknown, you were developing in JDK 1.1 which is embarassingly old.

    Arguments about the lack of ABS in the FORD Model T do not support the idea that modern cars cannot brake.

  20. Standard Pratice on Apple's G5 Speeds Challenged · · Score: 5, Informative

    I can vouch for those unfortunate enough to have worked in the grocery industry (and have an idea of what that kind of mechandising entail) but this is hardly insightful. It happens on nearly everything that you buy.

    When asking the pricing managers (which work for the chain, not an individual store) they replied that there was a study once done, indicating that there is a psychological tendancy to shy away from certain "maker" numbers as being too big. For example, the masses statistically believed that twenty dollars was too much to pay for item x, but for some reason, nineteen ninety-nine was not too much to pay for the same item. Funny thing is that with the same item, eighteen dollars would again be too much, but seventeen ninety-five wouldn't.

    Even if the study is flawed or bogus, it is still being taught in the "front-line" marketing schools, (ie. grocery, drug-store, clothing, etc.) , and so I expect we will see nineteen ninety-five for many many years to come.

  21. MD5 Checksums won't work on SCO Berates Linus' Approach To Kernel Contributions · · Score: 2, Informative

    If I open a bit of code, add a space, change a comment, and then submit it, the MD5 Checksum will be wildly different than the original. Assuming that the original was code I stole, there would be no protection for SCO (or anyone else for that matter). Heck, even opening and saving will modify the code (as my editor's settings automatically convert all tabs to spaces)

    I can't imagine that SCO doesn't know their "solution" is flawed, but I can imagine that they really don't care. I mean, an MD5 checksum of even their alledgedly "stolen" code would still differ, since they have stated that the files "contain" their code and are not their files outright).

    MD5 checksums per line? Won't work. Too many lines creating false positives (Anyone hold the rights to a line containing only ""? how about "/*"?) MD5 checksums per function / block / class / 20 lines? Still won't work. One quick pass through a code formatter, and all bets on a match are off.

    Of course, this isn't the only "broken" idea that will be thrown overboard as the SCO ship sinks, but Heaven help me, they can't sink fast enough.

  22. Anyone read the 3 other articles? on SCO Shows 80 Lines of Evidence? · · Score: 1

    Looks like this Aberdeen group has a bad recent track record getting the facts straight.

    If you read the previous 3 articles at their website, it paints a not so pretty picture for them. They reported AMD was bogosifying their "equavilance" mhz ratings on their chips as given to them by an "AMD insider." A few articles later we discover that it wasn't an AMD insider, but an Intel insider, and that they never checked their sources, credentials, or the accuracy of the report.

    Then they top it off by making a few harsh statements about Intel, but hey, it's like Aberdeen's mistake was, you know, "honest". That was slipshod journalisim at it's best, and using that last article to shift blame shows lack of accountability. Mabye it was an "honest" mistake, but I can't imagine a better matched "friend of SCO" for SCO to come running to in hard times.

  23. I disagree on OrbiTouch Keyless Keyboard Review · · Score: 4, Interesting

    All keyboards just need to report their keycodes to the machine (where the keyboard driver/definition translates them into the actual text encoding) The techonology has been around for years, and is quite flexible allowing multiple language specific keyboards to be attached to the same hardware.

    What is needed is really a user upgrade. People have invested a lot of time in learing exactly where the letters are located on their particular keyboard. (I know this as I recently had to "relean" the locations of various keys on a Spanish keyboard). Imagine asking someone to memorize (to the point of not thinking about it) the various dual-joystick combinations to type out a typical email. Or if not this device, the various mouse gestures (mouse based keyboard), hand wriggling (joystick based keyboard), eye-control (for eye-tracking keyboard), or other method of input.

    Certainly there will be adopters, but there will be a rough cost-benifit analysis by the masses. Most that will conclude it's more expensive to learn new keyboard type when the new keyboard only offers the same functionality of inputting text into a computer.

  24. Prior Art? on OrbiTouch Keyless Keyboard Review · · Score: 1

    Remember Karate Champ (1984 Coin-op)?

    Looks like basically the same interface, but without the flying flowerpots and of course the bull!

  25. Games changing sense of reality == bad on Law and Virtual Worlds · · Score: 2, Interesting

    In the real world, you can spend a lot of money and time producing something that is worth much less (if anything at all) than the resources you put into it.

    Why do people continue to believe that the things they arguably "create" online have a value equivalent to the amount of time and money they put into producing them?

    When OU was initially released, it had a realistic economic engine that ruined the game play. With todays economic engines, nearly everything you do betters your standing in the game. While this is good for promoting people doing things in the game, it has no bearing on the real world.

    So if you spend months building up the character on your game of choice and a you have a contract indicating that someone is willing to buy your character at a price, you should have a case (under the normal pre-existing laws), but you shouldn't expect compensation for voluntary work should you find it worthless (lost, erased, destroyed) after-the-fact.

    Disclaimer: Never played Ultima OnLine, but read interesting articles about online economic systems. Nor am I a lawyer, but if you think this is legal advice, I doubt a real lawyer could help in any way.