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  1. Summary completely pointless on Mathematics Says Romney and Santorum Tied In Iowa · · Score: 1

    The summary is completely incorrect (haven't read the article). What statistics says is that from the vote you can't tell whether Romney or Santorum is more popular among eligible caucus goers. The rules for determining delegates from the caucus are independent from the statistics of popularity. In this particular contest, this is only the first round and so it's hard to estimate how the final delegate count will end up. CNN estimates that the delegates will be split 7-7-7-2-2 for Romney, Santorum, Paul, Gingrich, and Perry, respectively. The AP, based on what appears to be a more careful examination of the rules estimates that the delegates will be split 13-12 for Romney and Santorum. (The AP estimate is based on congressional districts and since Paul and the others didn't carry any of the districts, they don't think they'll get any delegates). However, even the later caucus rounds are non-binding and delegates don't have to stick to someone who does poorly later on. What this means is that the entire point of the Iowa Caucus is media perceptions. What's more, since this is a caucus, the second part of the blurb makes no since, especially the part about ballots sticking. In caucus you count supporters, not ballots and they aren't secret anyway.

  2. Re:Looks cosy on NASA Shows Off Mock-Up of Mars-Capable Spacecraft · · Score: 2, Informative

    I believe that the capsule will only be the command center/cockpit/bridge of the spacecraft that is planned to go to Mars. The rest of the craft will be assembled in orbit from various Ares V launches.

  3. Not technically correct on Rocket Hobbyists Prevail Over Feds In Court Case · · Score: 1

    While APCP will not detonate, it will deflagrate (which is what it is designed to do).

    http://en.wikipedia.org/wiki/Deflagration

    APCP when burning produces large amounts of gases quickly, which if confined, will cause the container to burst (dry ice also bombs work on this principle). For safety reasons (more than fear of terrorism), the US Department of Transportation regulates shipping materials that strongly deflagrate as explosives under the HAZMAT cateogory of Class 1.3 explosives.

    http://en.wikipedia.org/wiki/HAZMAT_Class_1_Explosives

    There is a large misconcetption between a detonation and explosion. All conventional military bombs desgined to explode use a detonation as the mechanism because it is easier to control, more powerful, and more precise, but explosions can be caused by other mechanisms as well.

    http://en.wikipedia.org/wiki/Detonation

    Rockets are powered by materials that will explode under confinement (like gunpowder), but will usually not detonate.

  4. Re:General Assembly is worse on State of Kentucky Seizes Control of 141 Domain Names · · Score: 1

    It may be that this isn't a big deal to the various assortments of petty dictators, but they will often gang up on unpopular countries. Witness how the UN commission on racism is consistently and ironically hijacked by antisemitic agenda. It is worth noting that censorship is a universal concern for dictators and other autocrats and totalitarians. Control over the internet would likely inspire the various anti-freedom forces which make up the majority of the UN to work together for their individual benefit.

  5. General Assembly is worse on State of Kentucky Seizes Control of 141 Domain Names · · Score: 1

    While Russia does not have a veto over the General Assembly, I think putting something important in the hands of the General Assembly is much worse if you consider the percentage of UN members that are under the thumb of petty dictators.

  6. Windows 3.1 on The Thirteen Greatest Error Messages of All Time · · Score: 1

    My favorite is from Windows 3.1:

    "This application has violated system integrity . . ."

  7. Re:New Goddards? Let's hope so. on SpaceX Gets Operational License For Cape Canaveral · · Score: 1

    This will not be launched from NASA's Kennedy Space Center, but rather Cape Canaveral Air Force Base. They are adjacent and the Air Force provides some services for NASA, but the pads they are talking about belong to the Air Force.

  8. Re:We Already Have a Moon Rocket on NASA Engineers Work On Alternative Moon Rocket · · Score: 1

    Saying that we can use Saturn V to go back to the moon is like saying we don't need new cars because the Rambler is a proven automobile.

    Saturn V used 50+ year old electronics and systems. It would take a substantial effort to redesign, remanufacture, and requalify the parts that they used. Who makes vacuum tubes any more? You could redesign a Saturn V just like you could redesign an AMC Rambler, but why would you when you can design a system based on existing technology? The Ares rockets will use engines and systems in use today rather than that last used 30 years ago.

  9. Re:What about the old fashined way on DARPA Working On Arthur C. Clarke Weapon Idea · · Score: 1

    Liquids do not penetrate better than solids do. Solids tend to be harder and have a higher density and penetrate better. The advantage that liquids have in cutting is the fact that you ccan more easily set up a continuous stream of liquid and so they can have better erosive action. Shaped charge jets on the other hand are solids that only look like liquids because they are produced at high enough pressures that the metal becomes ductile. They are below the melting point of the metal. Shaped charge jets are essentially explosively forged nails propelled at high velocities.

  10. Re:What about the old fashined way on DARPA Working On Arthur C. Clarke Weapon Idea · · Score: 1

    You can cut through thin sheets of metal with a high pressure, sustained liquid, but to punch through tank armor an explosively launched nail is more effective. Liquid cutting works by erosion. It depends on sustined action to make it through. A shaped charge is a small, thin jet.

  11. Re:Bring the marshmallows on DARPA Working On Arthur C. Clarke Weapon Idea · · Score: 1

    Nope, shaped charges produce metal jets by hammering them so hard that they're ductile. They aren't molten. If they were molten, they would splash off the armor. The difference between an EFP and a shaped charge jet is, as you say the the shape of the liner and the shape of the projectile, but the physics is the same. Shaped charge jets penetrate further because of their shape not because they are "molten."

  12. Re:What about the old fashined way on DARPA Working On Arthur C. Clarke Weapon Idea · · Score: 1

    Shaped charges don't propel molten metal. They work by using enough force to make the metal ductile. If they were really molten, they would splatter when they hit the tank. I wouldn't be surprized to find out that MAHEM was not acually using molten metal either.

  13. Re:Bring the marshmallows on DARPA Working On Arthur C. Clarke Weapon Idea · · Score: 1

    This seems to be very similar to an explosively formed penetrator (EFP) or a shaped charge, only using a magnetic field instead of a conventional explosive. These are used in most anti-armor (tank) weapons. See here:
    http://en.wikipedia.org/wiki/Explosively_formed_penetrator
    EFPs are not actually molten though, the explosive charge just hammers it so much that the metal becomes ductile. I wouldn't be surprised if this is the case here.

  14. Re:That's fair on New Science Standards Approved in Florida · · Score: 1

    Exactly. Part of any science class should be the distinction between hypotheses and theories. Laymen use them identically, but to a scientist a theory is a hypothesis that has significant observed evidence backing it up and no evidence that can't be reasonably explained.

    If Intelligent Design/Creationism is mentioned in a science class it should be mentioned that it isn't a scientific theory (it's really a philosophy and in the scientific sense it's an untestable hypothesis) because it doesn't have any observable evidence to back it up.

    What we sometimes call Natural Laws are really theories. Evolution is not a "fact." Even the Law of Gravity is not a "fact." Only events are facts.

  15. SUVs in snow on Auto Mileage Standards Raised to 35 mpg · · Score: 1

    The ironic thing is that big SUVs are horrible in snow. Sure, the 4WD is good for getting started, but the large mass makes them really hard to stop on ice.

    If you live in an area with snow and ice you're better served by driving a small front wheel drive vehicle than a big SUV or if you're really worried a small AWD vehicle like a Subaru or Toyota RAV4 has all the benefits of the big SUVs for snow driving with few of their liabilities.

  16. This is why Firefox had to change its name on Bypass Windows With Fast-Boot Technology · · Score: 1

    This is why Firefox had to change its name from Phoenix to Firebird (where it ran into issues with an Open Source database program) around version 0.5. Phoenix BIOS people had already applied for a trademark for a Phoenix web browser. This has been in the works for years.

  17. English System Definitions on Kilogram Reference Losing Weight · · Score: 1

    Nowadays the English system is defined in terms of the metric system: for instance an inch is defined as exactly 2.54 cm, pounds are defined in terms of kilograms, etc.

  18. Parallels with Turkey on China Says Tibetans Need Permission To Reincarnate · · Score: 1

    Kurds and Western Armenians might be able to draw some parallels from China's treatment of Tibetans to Turkey's treatment of them.

    Turkey objects to the creation of any Kurdistan in Iraq or Iran because their Kurds might agitate to join, loosing a substantial chunk of their geography to them.

    Turkey is a lot better about many things than China, including relations with minorities, but they aren't exactly a shining beacon either. In fact they still deny atrocities that happened about 90 years ago under an oppressive regime that few liked and that they rose up against and overthrew just because it "insults" their national character.

    In the US we put some of the groups we robbed and exploited a 100 years ago on the dole. It doesn't actually help them move forward in the world as groups or individuals, but hey at least we said "our bad."

  19. Math is not hard, but the summary is wrong on Warner Bros. to Turn All 15 Oz Books Into Movies · · Score: 1

    The 15th Oz book (the first by Thompson) is also in the public domain. Evidentally the 16th is as well (published in 1922--not sure why it's not mentioned). This is why they are doing the Royal Book as well.

    The summary is wrong in that they didn't buy the rights to the first 15. Evidentally they bought the rights to the 1939 movie (some time ago) and plan to adapt the public domain books.

    I've heard that some of Thompson's later books are public domain as well because she didn't bother to renew them, but I don't know which ones.

  20. "Saint" Explanation on American Red Cross Sued For Using a Red Cross · · Score: 1

    The "saint" comment isn't a reference to Johnson & Johnson, but to Saint George whose symbol is also a red cross and is one of the national symbols of England (and one of the 3 components that make up the Union Flag of the United Kingdom: the red-on-white cross of Saint George, the white-on-blue saltire (diagonal) cross of Saint Andrew (Scotland), and the red-on-white saltire cross of Saint Patrick (Ireland--may have been created just to fit in the Union Flag or to parallel the English and Scottish symbols as strickly speaking Saint Patrick didn't have a cross symbol becasue he wasn't a martyr)). If you ever see English sports teams competing as England rather than as part of the UK, they'll use the red-on-white cross flag.

    Note, however, that the English flag has different dimensions than the Red Cross flag. In the flag of Saint George the cross goes to the edges of the flag/symbol, where the cross in the Red Cross flag does not being based on an inversion of the Swiss flag (white-on-red cross).

  21. Afraid of federal audits on NASA Contractors Censoring Saturn V Info · · Score: 1

    This is because one contractor got into trouble over ITAR and the others are all working to avoid massive fines and restrictions. Distribution of Shuttle-related material that used to be public is also becoming restricted. I don't believe that it's that they're afraid that a terrorist group is going to build a Saturn V or Shuttle, it's that the principles involved in designing a huge rocket are the same as those for designing a smaller rocket.

    It seems pretty foolish to try and "put the genie back in the bottle." Maybe they want space contractors to get into the habit so new designs are not made public.

  22. Re:Genetic traits over DNA on Ancestry.com To Add DNA Test Results · · Score: 1

    DNA on the other hand is still latereal in time and not verticle. Unless you want to test a corpse you can't go back many generations. A good tool to see what uncle Joe REALLY did on those "sales" trips in Vegas, but not much good as a family history research tool.
    On the contrary, DNA is a very good tool for telling which areas your ancestors come from. It just can't guarantee to pick up all your ancestory. What this service does (among other things) is look for "marker genes" that are specific to locations or families. There are enough "marker genes" that they can pinpoint part of most people's ancestory very well. It can prove you have ancestors from a certain bloodline or region (down to the village in some cases), but it can't prove that you aren't from some place or bloodline (except for some patrilinear bloodlines that have known Y-chromosome markers like Jewish Kohen (priests) (and even then it's remotely possible for some mutation to have removed the marker) and matrilinear bloodlines with known mitochondrial DNA markers).
  23. Re:What about the pound? on Perfect Silicon Sphere to Redefine the Kilogram · · Score: 1

    There are two systems of force and mass in "English" units.

    The first uses pounds for force (and weight) and slugs for mass. In this system a slug is the mass that accelerates by 1 ft/s^2 when one pound of force is exerted on it. A pound is the force exerted by one slug accelerating at 1 ft/s^2. (1 lb_f = 1 slug*ft/s^2)

    In the second, pounds is the unit of mass and poundal is the unit of force (and weight). The poundal is the force required to accelerate one pound 1 ft/s^2. The pound is the mass that accelerates 1 ft/s^2 under the force of 1 poundal. ( 1 lb_m = 1 pdl*ft/s^2)

    It works out that because the acceleration of gravity is about 32.174 ft/s^2 that 1 pound = 32.174 poundals (and change). 1 slug = 32.174 pounds.

    In practice a hybrid system is used where pounds are used for both and are designated pound-force and pound-mass to destinguish them. In this system a pound-force is the force required to accerate a pound-mass to the standard force of gravity (about 32.174 ft/s^2). A pound-mass is the mass with the force of one pound-force under standard gravity. In this hybrid system you have to introduce another constant into Newton's second law (F=m*a) due to the unit definitions in order to make acceleration a ratio of the acceleration of standard gravity, but it usually isn't too confusing.

    Stones, ounces, tons, etc. are all defined in terms of the pound. They are nominally weights (meaning they are multiples or fractions of the pound-force), but can be used as masses as well. For anything other than engineering loads, weights and masses are used interchangeably. All "English" units are nowadays defined in terms of metric units. 1 inch = 2.54 cm exactly.

    Incidetally, there is a metric version of these shennanigans where the kilopond (also known as kilogram-force) is the force of one kilogram under standard gravity, but it's hardly ever used (and is non-SI). The hyl or metric slug (used even more infrequently) is 1 kilopond*m/s^2. The SI (International System--standard abbreviation uses French initials) unit of force is the Newton (1 kg*m/s^2).

    As an additional gee whiz, there is an additional metric unit of force the dyne which is defined as 1 gram*cm/s^2. 1 Newton = 10^5 dyne. People mainly use the SI subset (also known as MKS--meter kilogram second) of the metric system, but the older CGS (centimeter gram second) is still used in some fields where it's more convenient. There was also a MTS system (Meter Tonne Second--where the metric tonne is 1000 kg) used in the Soviet Union.

    The relationship between the CGS system and SI is non-standard (i.e., you can't multiply the CGS unit by the same number to get the SI unit--although it is always a power of 10) which is somewhat annoying. There are also some odd-ball metric units like the calorie (heat required to raise 1 gram water 1 degree Celsius), the liter ( 1 decimeter cubed or the mass of 1 kg of water), and the Angstrom (10^-10 m) that are non-SI but sometimes used because they are more convenient or for historical reasons.

    The nice thing about SI is that it makes definitions easy to use and remember, but you sometimes end up with awkward units. The Farad (unit of capacitance) is extremely large. Most capacitors are in the picofarad (10^-12 F) to microfarad (10^-6 F) range. This is a Farad is defined as 1 s^4*A^2*m^-2*kg^-1 or 1 C/V (Coloumb/Volt).

  24. Critical point irrelevant on Strange Alien World Made of "Hot Ice" · · Score: 1

    There is only a critical point between the gas and liquid phases. Solid phases do not have critical points with other phases. The solid-liquid phase boundry continues, it just isn't always demarcated due either to running off the edge of the chart or lack of data.

    And the link you point to doesn't have any information on water phases. Another comment points to this page which has a really nice water phase diagram. http://www.lsbu.ac.uk/water/phase.html As you can see there are several solid phases that can exist at 573 K at somewhere over 1000 atmospheres (10^9 Pascals).

  25. Re:Trade deficit vs. National Debt on The Unauthorized State-Owned Chinese Disneyland · · Score: 1

    well not totally true: In Latin American debit market ( and some of the old east German debit ) Pressure is placed on the bond issuer to force the government to come to better terms, since if they fully default without a restructure in place, no one is going to finance the bonds without a huge interest rate. Well yes. If a government wants to get people to buy new bonds, they must make them attractive. I consider this an indirect influence, because it doesn't usually affect outstanding debt. One individual or entity also does not really have the power to dictate terms, it comes down to market pressure (trying to make the bonds more attractive than other investments).