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Comment list things broken in open office (Score 1) 421

problems i have had Math ML interpretation is screwed (though at least the math editor is typed but why couldn't they used a more acceptable syntax) no cross referencing or labels! shitty formatting errors when opening docx but this is because of their shitty "open" proprietary format (the world would be a much better place if M$bullshit had a smaller market share so we didn't have to put up with doc format problems again, its just a document format you fucktartds!). I seem to remember docx is an iso standard or something but only through heavy lobbying by M$, they half publish the standard so Oo cant interpret it. Even go0gle docs has a hard time with that pice of sh**. I just wip out the LaTeX instead, ahh that's better anyone can reed a .tex file or a pdf. also WTF is silver-light is it one of those vampire movies?

Comment Re:So probably 2,000,000,000 hole in economy. (Score 1) 236

day toook ooowwrrrr joooobbbssss!! they tooook oooour joooobs. space shuttle is not needed as the cold war ended 20 years ago! its expensive, and dose not compete with modern launchers. lets face it materials cost isn't the biggest cost of a launcher, its fuel and development, so why bother making the launcher reusable? also why bother sending up a crew of 7 and all the life support that requires? Thease people are highly skiled and no doubt will end up working for some other engineering company in the future, hey maybe one of the commercial space rocket manufacturers. There redundancy may even lead to better prospects in-the future. NASA is scaling back, as it shouldn't be manufacturing what it can get commercial, (this is the states right free market and all that BS), They need to concentrate on the next generation of space vehicles. so i agree, NASA isnt state well fair! Its like the certain politicians sticking there fucking ore in and telling NASA to use XYZ manufacture because Its in there constituency, And hey sure we have to bail out GM (would totaly been better if it got bout out by toyota or someone).

Comment Re:Should be reliable (Score 2, Informative) 334

gas turbines are more efficient than petrol or diesel or engines, as the joule cycle is more thermodynamically ideal. The only problem is they prefer to operate at a continuous power output. Rover tried doing this in the 30's with Whittle's jet, but that was a disaster, the advances in electrical drive trains may have fixed this. still its pretty cool.

Comment Re:hmmm (Score 1) 459

The correct equation for modern jet aircraft operating in the cruse climb regime is the Breguet range equation. modem airframes are designed to fly at a specific Mach number and angle of attack (maintaining a constant C_L) so to get the highest Lift to drag ratio L/D this is about 20 for aircraft such as the A380 and 18 for a 747. now from the range equation you can see that the available range scales with the speed M. the problem for a transonic airliner is that as M approaches 1 there is a significant drag rise, significantly reducing the lift to drag ratio. These airframes however are designed to take advantage of a boost in lift (the coefficient of) associated with the supersonic flow over the front part of the wing, and the increased M to maximise ML/D just slightly beyond the drag rise Mach number. M = 0.85 for Airbus and 0.9 for Boeing, i think Boeing picks a faster but slightly less aerodynamically favourable speed (burns a bit more fuel for the range) as costumers also have to consider the leas costs of the airframe being in the air, i.e. it pays to be a bit quicker. Supersonic airframes on the other hand have much lower L/D ~10 for concord but then M=2.2 so ML/D is comparable to the transonic airline, and these planes can be just as efficient in terms of fuel per passenger mile (and the jets are more efficient to) this is another neach speed for passenger transport, however the development costs (especially concord with only being able to test in the wind tunnel, no cfd in the 70s) and other complexities (The FAA) can make this uneconomic. in this case, MIT, we have another aircraft configuration in which M=0.7 so L/D must be greater than 29 to be competitive. As they state that they are burning 70% less fuel then L/D must be quite a lot bigger. as i gues the best L/D is achieved by sports gliders at about 60, then they must also be speculatively factoring in lighter materials, and improved engine efficiency for the improved fuel burn, (technologies which transonic aircraft would benefit from to). finally I have my doubts about Boundary layer ingesting engines. the engines them selves will have to burn more fuel to accelerate stagnant flow at the back of the aircraft to slightly more than the velocity of the aircraft in the opposite direction. the delta v across the engine will be bigger than in the normal case. The only advantage is that propulsive efficiency of the engine is improved because by filling in the wake of the aircraft with the jet you reduce kinetic energy losses. see However there are massive headaches for the first stage compressors of such a jet engine (the velocity profile is uneven and turbulent on the rotor, which will course stalling and surging and a reduced operating range), as noted and I doubt this will be worked out.

Comment Re:Uhm? (Score 1) 251

I have UNR 10.04 on my acer one (atom N270) it takes 25 seconds to boot to the login screen plus a further 5 seconds to login, 9 seconds of that were spent before the grub had loaded. only problem now is the shut down time is like 30 seconds just wasting my time... only issue i have with canonical is they locked the panel in UNR so you cant add applets!

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