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User: PudriK

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Comments · 92

  1. Re:Heat shielding is minor compared to orbital cra on SpaceShipOne Back in Action · · Score: 1

    From what I've read, you can enter with almost any profile, as long as the vehicle is designed for it. The corridors are a function of the vehicle's limitations. Ballistic weapons enter using a ballistic profile, which has lower heating duration which is easily taken care of by ablative materials, but large G-forces. The capsules, Apollo and Soyuz, are close to ballistic, but generate some small lift, but again, it is mostly a short duration of heating and larger G-forces.

    The Shuttle uses a low-G entry, requiring it to spend much more time exposed to the reentry heating, this is why ablative materials were not used.

  2. Re:Heat shielding is minor compared to orbital cra on SpaceShipOne Back in Action · · Score: 2, Informative

    You forgot to include the potential energy required to get from earth's surface to orbit.

    For LEO (200 km), circular orbit velocity is 7789 m/s. KE is 30.3 MJ. PE for 200 km altitude (from earth's surface to orbit) is 60.7 MJ. If you launch at the equator, prograde, then you gain 464 m/s, for an intial KE of 0.1 MJ.

    So total energy required to transport 1 kg to 200 km LEO from stationary at earth's equator, is 90.9 MJ.

    Of course, if you're burning the fuel along the way the energy requirement drops as mass decreases, and you also have to add in oxidizer mass, but I don't know the equations for that.

  3. Re:Armadillo Aerospace on SpaceShipOne Back in Action · · Score: 1

    So your point is pointless, then, because any aircraft testing would be more "showy" than rocket testing. By calling them "showy," you are implying that Scaled is performing these tests for primarily publcity reasons--which is demonstrable untrue.

    Scaled just logs their tests for those who are interested. They haven't issued press releases except for it's unveiling and when they broke the sound barrier.

    With all due respect to Carmack, there is a world of difference between doing rocket engine tests and development, and having a functional vehicle, even if that vehcile has not yet achieved it's full performance.

  4. Re:Global Flyer on SpaceShipOne Back in Action · · Score: 1

    Since those days, Scaled Composites has done a lot of projects for the military, only some of which (I'm sure) have been publicized. For example, they did a scale model of the B-2 for radar testing, and also a prototype replacement for the A-10.

  5. Re:Ladies and Gentlemen: The Scientific Method on What If Dark Matter Really Doesn't Exist? · · Score: 1

    While conversing about the lack of proof of God, a friend of mine once made an interesting observation, one that I hadn't heard before:

    He said, he wasn't sure if God existed either. But there was this concept, "God," which brought people together as a community to help and support each other. So even if untrue, it had powerful positive benefits.

    Of course, a lot of atrocities have been comitted through history in God's name, too.

    I guess what I've been searching for, since I am pretty much an atheist (the type who thinks God may or may not exist, since no one's proven either way), is a secular church. A community of good, generous, people who, despite being atheist, still believe in helping your fellow man, who meet regularly to discuss their thoughts about life and morality, and who support each other in times of trouble.

    The problem with modern secularism is that it has not adequately established at a good theory of secular morality. (Like Heinlein postulated.) If we do not believe in a Divine Judge, then how do we determine what is right and what is wrong? You obviously can't leave it up to the individual--society as a whole must have some say. Otherwise, I would be free to think that killing small children is good, whereas most people would agree that it is not. A good theory of morality would establish guidelines that society should follow.

    I think a start would be the Golden Rule, and also do not interfere with another's right to follow their own path, as long as their path does not intefere with another's. But of course, both of these are just concepts, not iron clad, and without a basis.

    Which brings me to my last thought, if one were
    to form a scientifc basis for morality, what would be the a priori assumptions?

  6. Re:station, the on A Brief History of the Space Station · · Score: 1

    You didn't pay much attention in high school science class did you?

    Any liquid has a vapor point, which is a function of temperature and pressure. If you expose that liquid to a vacuum (actually just very low pressure), it will vaporize. Also, many of the liquid fuels we use (ie hydrogen and oxygen) are gases that are held under high pressure to reduce storage volume and hence tank weight. Remember, too, that volatile means chemicals with low vapor points, not "explosive". Gasoline is so dangerous because it is volatile (it releases a lot of gasoline vapor), and it is the vapor which combusts.

    Of course, solid fuels don't have this problem.

    However, the other thing that needs to be noted is that gases will not combust unless they are in the right ratio. A tank full of fuel vapor will not burn unless it is mixed with an appropriate ration of oxidizer, and for most fuels this is not a broad range.

    Lastly, another risk of volatile fuels is not only combusition (low risk) and corrosive (high risk), but also a leak will result in a constant thrust applied to the vehicle, which will disturb the orbit.

    Not to say it can't be done, but all these factors, and I'm sure many others I don't know, must be weighed in selecting propulsion.

  7. Re:Zero-gee sex on A Brief History of the Space Station · · Score: 1

    As someone once pointed out that we've been sending mixed gender crews up there for years, so it's pertty likely that it's been done. That said, look what porn did for the internet? Perhaps once NASA cuts funding for the ISS we can fund it with the "art" film industry.

  8. Re:Philosophy of Simplicity on Plain Cell Phones Fading Away? · · Score: 1

    I almost completely agree with you. When I purchased my last phone, I wanted three things: good sound quality, long battery life, and some means to sync it. I have a Nokia 6360. It has gone a whole week without charging, it sounds pretty good, and I was able to sync all my friends' numbers from my palmpilot to the phone via the IR port.

    I too hate to deal with excess features. It may be petty, but it's that tiny aggravation of having to scroll through three extra useless menu items to get what you want.

    I used to carry my palmpilot around, not just for numbers but also for the datebook, pocket Quicken, and to do list. But I despise having my pockets bulge with electronics, so I started using the datebook on the phone for reminders. Usually this involves entering the info in my palmpilot and then beaming it to the phone, because it's easier to enter. I don't do this often, though, because the datebook and to do list on the phone are very cumbersome.

    I have had my eye on the phone/palmpilot combos for some time, but none of them have a decent battery life.

    What I would appreciate is a company figuring out how to make an efficient interface for these added features. Right now it takes me seven key presses minimum to view a scheduled meeting on the calendar. It should be max three.

  9. Re:Yeah, nice use of taxdollars. on US Govt Makes Times New Roman 14 Official Font · · Score: 1

    Being currently a govt employee, I can say, "he speaketh the truth." Being a computer type person, I am very good about keeping all my files in electronic format on the computer, and my file cabinets are mostly empty.

    However, many of my older colleagues are not as familiar or comfortable with using electronic documents, and they prefer to have paper copies. Also, there are many old documetns which were not migrated from our legacy computer systems when we switched to a MS based platform. So if I need to edit a dcument from 1995, OCR is likely the only option.

    In addition, we frequently receive documents from other agencies or contractors in paper form without accompanying CD or disk. OCR is the only way to incorporate these documents into another document for distribution.

    It doesn't happen often. So infrequently that we actually got rid of our OCR scanner recently, so I have had to use my own scanner. Which reminds me, the reason I got the scnaner in the first place. My boss at my first unit wanted me to make electronic a 400 page manual from c. 1982. He expected my to type it all in by hand... that lasted about two pages before I shelled out for a scanner and OCR software.

    Of course, being green at the time, I didn't realize I could have brought the document into where I currently work and had it scanned. Live and learn.

  10. Re:Outsourcing to India? on India Becoming a Major Hub for Western Job Seekers · · Score: 1

    Do you honestly think this is because all computer companies and IT companies are racist? The world it a bit more complex than that. I would think a combination of the following factors would come into play: Blacks still represent a large portion of the poor urban population, a problem which itself is due to many factors of which racism is only part. Until very recently most lower-income people usually did not have access to computers, and therefore their children were unlikely to have grown up using them. Since black people tend to congregate, it may be that within a given setting not enough have had a mutual interest in computers for a large number to pursue that course over others. In my personal experience, of several black kids I new in high school, all from upper-middle-class families and very intelligent, some very good with computers, none of them wanted to be computer guys. Many wanted to be doctors, and I think the others studied english or other liberal arts degrees.

  11. Re:Good on Star Trek: Enterprise in Danger of Being Cancelled · · Score: 1

    It's not just you--I agree wholeheartedly. I enjoyed TNG and DS9 around the same time, and lost interest for the same reason. (Actually, I lost interest in TNG after a while, too, but that was more because I got sick of Sci-Fi that was too thin on the Sci.)

    Same with X-Files. Sci-Fi shows are best when they pose interesting circumstances that make you think about reality or people or society. For example, I enjoyed the TNG episode where Riker was in the play, but in reality was being interrogated, and in the end his mulitiple realities came crashing apart.

    But in all of them, X-Files, Babylon 5, DS9, writers weem to find the need to create these all-encompasing good-vs-evil plots that, to me anyway, are boring.

    I see life in a much more sophisticated fashion (I like to think), and I'd bet most "geeks" do too.

    Off topic: As for thin Sci, I took an immediate liking to Babylon 5 when they I saw they used spin for gravity and real physics for their spacecraft (reaction thrusters, engines not continually running when cruising...). But that didn't last long.

  12. Re:Want to be Subversive? on Biometrics in the Workplace · · Score: 1

    The scary thing about these security systems is not necessarily what they can do to us now, while we are good, law-abiding citizens, but what they can be used for if our government forgets that we citizens are supposed to be the soverigns of our state. It would be very difficult to organize an effective resistance (legal or guerilla) if the government can track your every move, read your communications, and selectively eliminate members of your group for various "infractions."

    This is the part of privacy laws that frightens me the most. I am all for the government finding more efficient ways of maintaining law and order, and businesses maintaining efficiency, but there has to be enough of a gap in the system to permit people in some way to organize outside of the establishment systems, in order to share news of abuses and organize effective counters to government and executive abuse.

  13. Re:Swipe Card on Biometrics in the Workplace · · Score: 1

    Then perhaps police officers should not be permitted to patrol the streets. After all, they may happen to see someone do something illegal, and that would violate their right to privacy.

    I mean, how dare they sit by the side of the road and watch me, just waiting for me to do something!

    Give me a break!

    The use of cameras is just a means to increase police productivity through technology, same as any other field.

    If you would prefer, we can pay the taxes necessary to employ a police force large enough to station on every street corner, so we can do it the old fashioned way.

    If you want privacy, go somewhere private.

    Not to mention, the use of cameras actually protects citizens--police cannot use illegal methods if they also run the risk of being caught on camera.

  14. IBM dumps Windows for OS X on Where Will IBM Drop Windows? · · Score: 1

    ...could it happen?

  15. Re:What's next on iTMS Named Fortune's Product Of The Year · · Score: 1

    There is another alternative that some musicians have successfully pulled off. The most recent I know of is Mandy Moore... Sell out, get rich and famous... Then take your rep and use it to do what you want. In her case, her latest album is her singing 70's love songs, but she used pop-candy music to get there. Of course, I doubt she'll make much money on her new record. (Like Garth Brooks with the Chris Gaines album.) But if she's smart, she'll save what she has, and use it to finance a quiet life making the music she wants. Of course, that first takes the incredible hard work to go from a person-who-likes-to-sing to a model/dancer/actor who can lip-synch and has enough cojenes to be half-naked on a national magazine. It all comes down to marketing... you don't make it big unless a big label fronts the money to plaster your face all over the place and push your single onto the radio.

  16. Re:History shows productivity boots everyone on The Robots are Coming · · Score: 1

    You are ignoring that that innovations in agriculture during meant that many peasants were able to move into the cities, and by the 18th c. had become the primary labor of the industrial revolution. This would not be reflected in their familial names. Right now the loss of manufacturing jobs in the US seems to be more the result of moving them overseas than to automation. Also, I think you don't take into account that modern life is much more mobile. It is much easier these days to learn a new trade, move to where the work is, or for your kids to do something completely different than their parents. So I don't forsee two centuries of proletariat poverty anytime soon. I would be more concerned with bringing much of the third world up to the standards of the developed world, and part of this will involve moving jobs from "developed" coutries. As for your bleak view of the future, I don't know what to say. I would consel that you don't want to "stop" governments... first, as an individual, you can't. Second, you have to work within the established systems to transform them in the directions you seek. If you think this can't be done, I would point to the progress of entire last century. Yes, marches and demonstrations get the word out, but it was specific laws that changed, thanks to the self-interest of politicians following public sentiment, not any revolution.

  17. History shows productivity boots everyone on The Robots are Coming · · Score: 2, Interesting

    It's also not as simple to say that all these people will be out on their keister, except for the one repair guy. History shows that mechanization and boosts in productivity benefit everyone, starting with the use of agricultural machinery to get people out of the fields. Yes, in the short term jobs are displaced, but the increase in productivity means that fewer people are needed to generate one commodity, and so that the remainder are free to open up new lines of business and create new services and commodities. There will always be a group of obselete workers, but I would take issue with anyone who says artificially protecting their jobs is for the greater good.

    The worst case, unfortunately, is that if you artifiically protect certain jobs, they will be moved overseas to where those protections don't apply. In the short term, those workers keep their jobs, but in the long term, the economy of your nation is put at a disadvantage from your neighboors, and that hurts everyone.

  18. Re:We must establish private property in outerspac on Orbdev Files US Federal Suit Over Asteroid Claim · · Score: 1

    In a similar vein, as individuals we owe our property to the defense of the state. As individuals we would be hard-pressed to defend our land from the Government, but as a mass of citizenry, we defend our personal property "rights" by exercising our votes, and in the end, by revolution if necessary.

    Someone once poitned out to me, you don't actually own your land in the US, because you have to pay property taxes on it, and they can throw you in jail if you don't.

    The reality is, the only way you own anything is by your ability to defend it. In a well-established civilization, we defend it by contstructing a Government system which tends towards the defense of "personal property." Over time, of course, control over property can be wrested from the people.

    For example, Neal Boortz has been making a big issue lately over the use of Eminent Domain laws to wrest property from individuals so that corporations can develop the land, ostensibly in the "public interest" because a Wal-Mart will produce more tax revenue than a few houses.

  19. Mod Parent Up on Orbdev Files US Federal Suit Over Asteroid Claim · · Score: 1

    Thank you. Very well said. I couldn't believe someone actually wrote that ignorant drivel that started this thread.

  20. Awaiting digital ink on Bubble Bursts for e-Books · · Score: 1

    I agree. eBooks have all the advantages of an electronic format, but reading any lengthy document off a screen gives most people a headache. (Slashdot sample not typical.)

    Once digital ink or some other ambient light display with a fine pitch is realized, more people will be comfortable with reading an electronic novel. Of cours, this will have to married to a durable, lightweight, long-lasting frame that has all the same ergonomic benefits of a paperback.

  21. Re:KDE myths on Windows XP Edges Out KDE in Usability Test · · Score: 1

    Wow. Whining about whining.

    We are all aware of our right to use whatever WM we want. The point of these discussions is to elucidate the differences between the two so that we can make an informed decision. Your argument, or lack thereof, is equivalent to jumping into a political debate and saying, "it doesn't matter, vote for whomever you want." Stop wasting bandwidth.

  22. Another lemon? I'll use a laptop instead. on New High-End HP Calculator? · · Score: 2, Insightful

    I covetted my 48G in high school. The ability to store data, make simple programs, RPN, and the equation/constant library were powerful tools. Everybody else used TIs. In college, I convinced a EE buddy to buy a HP48, and he was much happier with this choice.

    They announced the 49G when I was in m last year of college. I was excited. The 48G with a CAS! Instead, what a disappointment! Stiff keys, constant need to upgrade the software to fix bugs (through a cable I had to jury rig from an old serial mouse cable, because it didn't come with one), no equation library, and the frequent pauses in the software in the middle of simple calculations. And the OS, especially the way the memory was handled, was cumbersome and confusing. Same screen and same slow processor. Not a purchase decision I'm proud of.

    Given their recent history, I have a lot of reservations about the quality of this product, and doubts that they will make any inroads into the education market. Once again the screen and processor seem to be stuck in the past.

    HPs used to be THE calculator for engineers. I'll still use my 49G for classes where computers are not alowed, but for everything else, I prefer MATLAB. Although it is a lot more expensive, MATLAB, MathCAD or Mathematica on a small laptop seems to me like the ideal tool for the modern engineer.

  23. George Mason's Virginia Declaration of Rights on RIAA Obtains Subpoenas Against File Swappers · · Score: 1

    Since you couldn't be bothered to include it yourself:

    XIII
    That a well regulated militia, composed of the body of the people, trained to arms, is the proper, natural, and safe defense of a free state; that standing armies, in time of peace, should be avoided as dangerous to liberty; and that, in all cases, the military should be under strict subordination to, and be governed by, the civil power.
    From this link.
  24. Re:Creeping Doom on Gamers Aren't (Always) Geeks · · Score: 1

    Please read more carefully. I said:

    But, like watching TV, gaming involves very little physical activity. (Unlike TV, at least it exercises the mind.) So it needs to be balanced with some form of physical activity.

    Rephrased simply: Gaming does not involve physical exercise; and TV does not exercise the mind, but gaming does.

    An activity cannot be precluded by statistics. Just because most pro basketball players are black, doesn't mean a white player can't be a pro. It is definitely a cause-and effect relationship, because there are only so many hours in the day, of which only a few can be spent on recreational activities. Hence, time spent gaming is time that can't be spent exercising, and most "hard-core" gamers do not get any.

    As for gaming and TV, like I said originally, it doesn't involve thought. Even TLC and DSC, while educational, do not require any active mental participation.

    Your last point is good. On-line gaming is not entirely safe from predation. However, most "gaming" done by kids is not on-line, yet. Wouldn't it be a neat turn of events if parents pushed their kids out of the house and off the computer out of fear of on-line predators, thinking their neighboorhood is a safer place to play?

  25. Re:Female Character Problems on Gamers Aren't (Always) Geeks · · Score: 1

    I dunno, that sorceress had some nice legs, until you put armor on her.

    Seriously - almost all male avatars are tall and barrel-chested. Do I resent not being able to play a short, spry character? Sometimes, especially in FPS games where size does matter (smaller target). Are these big brutes "sex objects," or just an idealized physical form?

    I could argue that in both cases designers are choosing to model the same idealized shape that we are presented every day in magazines, TV, movies, etc. Both characters are being used to run-and-gun, so their activity is not sexual in nature. The female's Barbydoll figure is not so much because the designers expect young boys to fantasize about it (Tomb Raider aside), as it is expected in modern media that all body forms will be ideal, unless an effort is being made for realism.

    I remember reading an article when Tomb Raider was first made. The designers were going to do third person, and they said, well if you're going to be staring at the character's butt all game, it might as well be an attractive female rear. This made me wonder, do women find the rear ends on male characters attractive, or have 3-D artists been remiss in crafting the perfect male derrier?