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  1. Re:Waves or Waves on Gravitational Wave Detection Imminent? · · Score: 1

    Yeah, I was kinda hoping to avoid the whole question of exactly what the "stuff" was by using such an obviously rubbish phrase. The wave/partical duality of photons serves only to confuse the point about the difference between the two types of energy propogation, sound and EM.

  2. Waves or Waves on Gravitational Wave Detection Imminent? · · Score: 2

    Ok, so are these gravitational "waves" real or just a construct to explain gravity?

    Essentially the trigger for this question is the whole sound/EM difference. EM is acutally the emission of "stuff" whilst sound is the propogation of energy through a medium and without the medium there is no sound just the vibration of the original source.

    It's been a long time since I read any theoretical physics and so my head hurts a little when I think about this stuff, but the "dents in space time caused by mass as balls on a rubber film" metaphor help explain the "pull" of gravity really quite nicely, if it is even remotely true. But that model suggests a "medium" through which gravity acts.

  3. Re:Not execution speed, but predictability on Help crack the Java 1.6 Classfile Verifier · · Score: 1

    Please. I am deploying on a variety of platforms from 1.5GHz UltraSPARC III to Opterons none of the machines have less than 4 Gig of Ram and the only reason my system cannot do more than the 12000 transactions per second that it can currently do is because the CPU is at 100% all of this is in a resilient (any machine can fail and the system keeps running) environment that can be deployed across a wide geographical area supporting thousands of users. The critical issue is that each transaction needs access to all the data in the system (potentially) and it is not predictable from the data in the transaction alone what that data is and so the problem domain is not (easily) parallelisable.

    So heres a word of advice, not all problems are trivial. When performance is really hard, Java simply cannot compete, not even playing the same game, not even close. System programming

  4. Re:Not execution speed, but predictability on Help crack the Java 1.6 Classfile Verifier · · Score: 1

    To all those griping about how "garbage collection is really much better" and "In some cases generational GC can be faster than manual memory management by all but the top 1% of c/c++ experts" and in particular saying that "A compiler means you have no real control either; well I am sorry but you are wrong on both counts. First I only used GC as an example and it still stands since the GC whilst perhaps continuous it is still out of my control. As for the compiler issue, my point was not about speed RTFT but predicability and once my compiler has run on my code I can happily be sure that the code will follow the same execution path each time I put in the same data. I have never hand tuned the code but when I find performance issues I can provide more and more business level functionality to help me improve the performance of the core system functions because I know the execution path that is going on under the hood (even if I don't know the sepcific instructions. As for malloc, and other OS resources, you are right creating new ones during running would be a problem which is why we alloc the 3 gig and several hundred semaphores etc at the start of the run.

    As for top 1%, I disagree, but I am certainly starting to care about how I layout my memory structures in RAM because I am suffering too many page faults out of the level1 or level2 cache on the the processor and reading from memory is just non-optimal when that happens, particularly if I can keep the structures I use within one transaction in the cache. Stuff like Java just can't give me that control.

    The responses I saw to the OP highlight the defect I was pointing out in the first place, when you are pushing the edge of a CPUs performance or when your problem space is not inherently parallel then languages like Jave do not cut the mustard. Most Java programmers (C#, and other "interpreted" languages as well) just don't seem to understand this issue.

  5. Not execution speed, but predictability on Help crack the Java 1.6 Classfile Verifier · · Score: 3, Insightful

    Look, I wish people who keep banging on about how Java is nearly as fast as C would get their heads out of their asses and realise that the biggest defect in Java is not raw execution speed but the "business processing" holiday that the system takes every "completely unpredictible once in a while". If I have a throughput capacity system, I can control the rate of throughput in a number of ways (eg selling less than my total capacity and then throttling at times of peak use) but when the system goes and does something like a garbage collection and the whole pipe goes "fnark" for a some seconds I am quite pissed since my users who want the service level in their SLA aren't getting it.

    Predictability and execution control are why I use C (and to a lesser extent c++) not Java. That cannot change for languages that give me no control over the raw execution path.

  6. Re:Your tax dollars at work ladies and gentlemen on Ma Bell is Back · · Score: 1

    You are right. It is a monoploy. A natural monopoly. I defy anyone to explain how running wire to every dwellling in the country (or even a region) is somehow "imporived" by competition. Running two such wires from competing suppliers is just such a waste of capital. Much like the roads which are funded by the state (with some exceptions, exceptions for which there may even be a parallel in the telco case). So the infrastructure should be funded by the state, with specific cable running jobs able to be contracted out to those who can do that job better (cheaper, faster?) and then business can provide services over the infrastructure; voice, data, video, or even just data with everything else just a subset. Certainly this makes more sense in terms of running fibre to everyones home. That should be the next goal. Just get everyone to chip in run one lot of glass and then let the margins appear in the content/service and not in gouging out the cost of capital for the channel itself. It is just so freakin; sensible.

  7. Many Posters Missing the Point on How Darwin Managed His Inbox · · Score: 3, Interesting

    Many of the posters here are say in various ways, "Big Deal, they responded to mail the way we respond to email, so what?". But it is an interesting finding.

    But there are many components of the analysis that need to be understood. First, assuming that the mail was from their celebrity period then we should ask does pre-email celebrity present a parallel to email in terms of unsolicited incoming messages. If so does it present a way of trying to manage it.

    Second, the fact that people in the pre-email days are responding to the same kind of fractions as we are with email then we can try and understand if email is a complete parallel for regular mail. In which case many things follow, for exampl the question about whether the "massive" penalties for mail interference should be extended to email.

    Then we could think about the social impact of mail. Is the proportion of responded email a "guilt" thing or a measure of the relevance of the mail. In otherwords do we reply to X% of our mail because to do less makes us feel bad and if we bump up the number of incoming does the amount of responding increase, or do we settle for a lower X.

    These are all interesting questions and historical data from a parallel, perhaps corellated, source is a worthy place to do analysis.

  8. Re:Welcome to reality.... on Are Skimpy Raises the New Normal? · · Score: 1

    company I work for and many, many others are having record years, the owners fortunes increases drastically each year because we do such a good job, WE, not THEY, because without us, they would not be rich, but without them, we couls still produce and sell the same product.

    Then become an owner. Just buy the company stock, or even better ask them to offer you an employee share purchase scheme. Even in America this makes good commercial sense for them and a tidy little benefit for you without damaging the bottom line.

    However, don't over value your contribution. Think of the pain it would cause your billion dollar business if you were incapacitated tomorrow? Chances are not much. If I died tomorrow my boss would be screwed until he, or another of my colleagues moved to the country (and timezone more importantly) where I am currently a key resource. How much would it take to make that happen? Well certainly less than half my current salary probably nearer a quarter. It would take about a week or two to get that wheel in motion. I ain't under any real illusion as to my own importance (and I am relatively important).

  9. Recollections on Andy Tanenbaum Releases Minix 3 · · Score: 4, Interesting

    I was "there" when Andy and Linus had their first "ding dong". I was doing an OS/Design undergraduate (300 level) course at the time using the AT book and MINIX as the tool through which we had to implement changes to the scheduler. The book was excellent, MINIX was pretty cool but more importantly it was an educational tool to allow us to delve into the guts of an operating system and play around with it. It was so accessible and relatively easy to do, certainly compared to anything else available at the time.

    Cruising the newsgroups was pretty much the done thing at the time and comp.os.minux was pretty high on my list for obvious reasons. Saw this stuff happening at the time and, knowing that AST was always pretty direct was entertained by the whole flame war thing. Anyway my point is that AST saw MINIX as a OS theory educational tool and Linus saw it as too defective to be even that and as such Linux was better. Funny, I agree with them both, kinda. I could never have kernel hacked Linux like I did MINIX at the time and MINIX could never have become my primary desktop at home like it is now. I guess they were just talking at crossed purposes even then. Pretty much standard flamewar ;-)

  10. Departure Tax on Space Tourism? · · Score: 1

    There are certain things in life that should have a 1000% "too much freakin' money for your own good tax". Included in this category are 10,000 dollar mobile phones and space tourism like this. Anyone with enough money to drop 11 mil on this should be forced to build a school or a hospital wing first. Oh, and it should be a departure tax (rather than a return tax) so that if the blow up along the way they still have to pay.

    Can I buy duty free? Do I have to take it with me when I go or can I buy it on my return?

    Just some thoughts.

  11. Re:Go Australian Scientists .... on Insect Substance Synthesized For Science · · Score: 2, Insightful

    The issue is not that the Government should be doing the invention but that Australia has a history of breaking ground, passing off the "value add" to other countries and then buying back the value added product. In particular with respect to some pretty fundamental science. I am not sure I am in the same boat as the poster with respect to their feelings about that situation, but the point is certainly arguable that a little more government investment in those inventions would benefit the whole country greatly and continue to do so in the future. Such investments, according to the poster, are probably good investments from a socal perspective.

  12. Re:Do No Evil on Google Wants a Piece of AOL? · · Score: 1

    Google is a publicly traded company. They by law has to maximize the profits for their shareholders.

    That is such a crock. Actually the board of directors have a fiduciary duty to the shareholders which means they must excercise their authority (derived from the shareholders) in such a way that is compliant with the corporate entities rules (as defined by the Articles of Association, are they still called that in the US?) whilst representing the interests of the shareholders. That's it. There is no "mandate" to maximise profits. Even if their was such a mandate it is up to the board to interperet the best way to do that which is not always "rape the business for every cent this financial year". Indeed it is the management team rather than the baord who make those kind of decisions but it is the board that determines how the management team is compensated and so selecting a scheme and a team that does no evil is completely consistent with their fiduciary duty to the shareholders.

    In Googles case doing no evil might well be a strategy that is not only cool and nice but objectively good for the shareholders since "goodwill" (a close corollary to reputation) is a very significant component of any non-asset, brand based business and Google is _certainly_ a business like that.

    The assumption that "for profit" means "must make as much money as possible" therefore "must do evil" is not justified in theory or in fact.

  13. Re:Fire good! on Archimedes Death Ray · · Score: 1

    IMO, ancient Greece was pretty much as technologicly advanced as 15th century Europe. Why we ended up having the industrial revolution, and the Greeks did not, becomes a very interesting question.

    Excellent question. One that I have pondered as well. Actually as much about the Romans as the Greeks. The one that gets me is that the Romans had a steam powered toy the Aeolipile which is very close to a steam engine. Imagine if they had begun the same technology expolosion that resulted from the steam engine in the 18th century, we might be 1000 years further along the technology tree!!!

    One of the most interesting theories I have read about why the IR happened in the UK rather than anywhere else because of tea. Perhaps the population density requirements could not be met by the Greeks or the Romans.

  14. So the images would go into... on Distant Planet Imaging Project Gets More Funding · · Score: 3, Funny

    Google "Not" Earth then.... Or maybe GoogleGalaxy.

  15. Painful but not peculiar on Apple to Replace Faulty Nano Screen · · Score: 1

    I am on the second instance of my MP3 player (not an ipod of any kind) because I treated it without the proper regard and "cracked" the LCD, you know that lovely inky blacness of a broken backlit display. I now have a special piece of "cassette tape/CD jewel" case sticky taped over the screen and have it in the special protective pouch. Looks shit, doesn't scratch and would probably survive a decent sharp point impact (definitely from my keys).

    It's all good. It kinda defeats the purpose of a sexy new ipod though, wrapping it is hard plastic and a cover. Probably why I wont buy one.

  16. Re:Time for new comparisons to be made. on MySQL 5.0 Candidate Released · · Score: 2, Interesting

    Easy just report;
            Performance Prettiness Completeness
    1. MySQL Firebird Postgress
    2. Postgress MySQL
    3. Postgress Firebird
    4. Firebird MySQL
    5. ... ... ...

    Then oracle has no problems with the report since you are _not_ reporting anything about them.

  17. Use the Purpose of the definition on How Would You Define a Planet? · · Score: 1

    First IANAA, but for me the purpose of the definition of planet operates within the context of a Solar System. And there are a number of astronimical concepts, for most of which I do not know the technical details. But, it seems to me that the set of planets within a solar system come from the set of objects that orbit around the star(s) in question.

    Then I think we add a proviso that the object must nver have a retrograde movement in relation to its orbit around the star. This would eliminate any object that orbits an object that orbits the star(s) in question. (I think)

    Then perhaps we can use the lagrange points to help eliminate the small and/or the eccentric. This is probably some function of the radius of the Hill sphere since that radius is a function of the mass of the objects (the object to be classified and the mass of the start(s)) and the distance from the object from the planet.

    Why is this definition useful? well, perhaps it isn't however in my view if we ever get of this rock then objects with somehow conveniently sized Hill spheres might have some suitable orbital features that make them qualitatively different to those objects that do not have such conveniently size Hill spheres. In fact, it is this issue that is at the source of my "astronomical feature" definition since objects that fall into the category (however it is defined) are inherently more useful than ones that do not. they would be the planets.

    Just a thought

  18. Re:Environmentalists Caused the Grenhouse Effect on Lightning Fusion And Other Hot News · · Score: 1

    And there is just one of the fscking hypocracies of the whole movement. What happened? Did Nuclear get less evil? or did the alternative get more evil? I would love to think that the net global evilness is decreasing but I suspect that the alternatives just got eviler and so as far as the greenies (or perhaps watermelons is a better phrase, you know, green on the outside but pink in the middle) in a world that is getting just more and more evil nuclear is becomming acceptably less evil than anything else....

  19. Vertical screen space on Ultimate Software Developer Setup? · · Score: 3, Interesting

    Many people here have talken about multiple monitors but nor about their orientation. I find that vertical real estate on my screen is more productive than horizontal space. I would go so far as to say that 4x4 is an ideal monitor displacement. It would be so nice to get them "border free" as well

  20. Kangaroo on New Twist on Power Walking · · Score: 5, Interesting

    Sounds a lot like the energy differential shown by hopping kangaroos. Their energy consumption is remarkably low given the velocities they generate and it seems to be the result of energy stored in their lower leg tendons. In other words they are using the same benefits to get a large increase in overall energy output with a marginal increase in metabolic consumption.

  21. Re:life expectancy really isn't increasing... on Scientists Discover Possible Anti-Aging Gene · · Score: 3, Informative

    Sorry, but that is just wrong. Many factors from hygeine to nutrition are actually making people live longer (not just he bump to the average cause by the decrease in infant mortality you mention). That is before we even consider late adult health care that makes heart attacks and strokes survivable.

    Our health is massively improved due largely to hygiene and nutrition because despite the damage that diet can do, the benefits of the improved nutrition of the last 50 - 100 years has lead to larger fitter bodies with almost no incidences of malnutrition in the developed world. The proof is in the life expectancy of the under developed world where both these factors do not exist.

    I cannot get the stats to hand but if you take out mortality in the first five years (which would eliminate the skew you mention from neo/post natal care) then the expected age of a developed world human is vastly greater than it was.

    Further evidence of this is the graph of resting pulse rate vs life expectancy of mammals. It is a remarkable fact that "apart from humans" all mammals exhibit a direct correlation between heart rate and life expetancy to the extent that mammals all seem to have the same number of heartbeats in their life (statistically speaking) apart from humans who are way off the graph with many many more heart beats than normal mammals. Such a contrary position is hard to explain from simple physiological differences.

  22. Re:You live in an ivory tower on Lockheed Martin Hardware to Protect NYC Transit · · Score: 1

    Hypothetical answer,

    Under what "law" is the State entitled to assign this cop to me? Is it covert surveillance? In my State this kind of directed surveillance requires court sanction. Therefore it is protected from abuse by the rule of law.

    As for the inappropriate use of CCTV footage. It is impossible to support this kind of monitoring without appropriate controls. The idea of a blooper tape is an excellent example, the offence that one would be committing by making one is very, very serious in the UK. A breach of a number of laws (see another poster that mentioned the specific legislation) and the laws are already in place.

  23. Re:Guise? on Lockheed Martin Hardware to Protect NYC Transit · · Score: 1

    actuall the CCTV footage was used to identify where the bombers joined the underground (Kings Cross Tube), and hence where they entered London (Kings Cross Rail) and hence where they joined the transport network (Luton) and hence the car that they left in the car park at Luton Station. All within about 24 hours.

    They did this by scanning _all_ the CCTV footage of the underground for guys with back packs and radiating outwards from the bomb sites.

    This speed of analysis, yet alone that the analysis was even possible at all was dependent on CCTV.

  24. Re:You live in an ivory tower on Lockheed Martin Hardware to Protect NYC Transit · · Score: 1

    No slippery slope?

    No. No slipery slope. You see you are forgetting a very important distinction about "public" transport. It's public. When you choose to participate in public life then your private rights are mitigated by the public need. I am a vehement believer in privacy and the right to exclude the State from interfering in my private life, but travelling the subway is not private life. You may make the valid argument that there is not a public need for this level or monitoring, but it is just that an argument. One in which there are two sides and one about both sides have validity.

  25. Powered re-entry on Carmack's Throatless Rocket Engine · · Score: 1

    It certainly seems to me (IANARS) that powered re-entry is the answer to the most problematic architectural problems of spaceflight. The biggest problem with powered re-entry is that you have to take the fuel up with you to slow during re-entry. I see many stories about Mars missions and the like making the fuel at the destination for the return journey. Is it possible to do the same for orbital flight? What mechanisms could we use for an "orbital" fuel manufacturing station.