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Submission + - The space sim isn't dead after all! (

cwebster writes: Chris Roberts' (creator of the wing commander series) new foray into PC games is officially a "go". The new game, Star Citizen, is slated to be what anyone who has played wing commander or privateer dreams it could be. Best of all, Chris cut out the publishers (EA owns the rights to WC) and is self funding this project. There are 20 days left in the funding campaign to meet the ambitious stretch goals. Contribute at kickstarter or the main site for the game.

Comment Re:For these 'fastest' metrics: (Score 4, Informative) 135


Weather modeling (solving navier-stokes and a few other equations on a discrete cartesian grid or on a spherical grid in spectral space). Add in land surface models, ocean models, data assimilation, chemical processes, and then crank the resolution way up and you need a lot of power.

DNS (direct numerical simulation) -- if you want to simulate a fluid flow with turbulence and you want to resolve the turbulence explicitly you need to have a grid spacing in your model that is smaller than the kolmogorov scale. For some flows this may produce a grid spacing measured in millimeters. If you want any decent sized model domain, this produces a lot of grid points.

Monte-carlo type simulations -- i.e., run a simple simulation but do it 1e50 times to amass a statistical representation of the process.

and lots of other types of modeling. Basically if you have a set of partial differential equations that tell us something and you need to solve them numerically (no analytic solutions, etc) and need to do it on very large domains at high resolution and your neighbor grid dependencies are such that your problem is parallel, then a supercomputer is for you.

Comment Re:Not too suprising (Score 3, Insightful) 372

No reason this should be restricted to apple products as an android tablet would work just as well to view pdf files, but still, very reasonable savings estimate.

You dont know the FAA then. I have two headsets, a Bose X and a Lightspeed Zulu. Both have the same 1/4" plugs and the slightly smaller one for the mic, both transmit the audio to the headset, both have (various degrees of) noisecancelling microphones, both use active noise cancellation.

But.... one has been shown to conform to a technical standards order (TSO) and one has not. So I can wear one of them at work, and one of them I cannot. All the TSO is btw is some standards on how the headset performs in certain situations, but the mfgr has to pay for the testing and certification. Both headsets work great, in fact the non-TSO one works better, but since word came down that we were not authorized to use non-TSO equipment, I cant wear it.

Its entirely plausible that apple has gone through a special certification process, and others have not. Typical of the FAA the certification is restricted to specific models, so you couldnt do something like certify "android", you would have to certify a specific hardware model with a specific version of the android OS.

Comment Re:How about just an iPhone and save even more? (Score 2) 372

Sit inside an airline cockpit once in a while, the majority of planes cannot do what a G1000 can.

Charts absolutely are used. On an approach, both pilots will have the approach plate (paper or otherwise) open and able to reference during the procedure.

The FMS, btw, is not why a B747 can execute a cat III landing. The aspects to that include crew certification (have to do a bunch of stuff in a sim to get certified), crew training (special procedures between the pilot flying and pilot not flying to setup the avionics, monitor the avionics and make the land/go around call), aircraft certification (there are extra sensors and instruments on the airplane with painted critical areas around them that must be free of dents and irregularities on preflight; the flight computers do more sensitive inter-comparisons between all of the instruments, the localizer is tracked with more sensitivity, radar altitude is used rather than pressure altitude), and airport certification (specific lighting systems must be installed and used, and the localizer and glideslope must be usable to the surface).

There is a lot more that goes into being able to fly and actually flying a cat III (my plane could only do cat II, but the concepts are the same) than just programming an approach into the FMS and engaging the autopilot.

Comment Re:How about just an iPhone and save even more? (Score 5, Informative) 372

The checklists shouldn't be going anywhere. Disclaimer: I dont fly for AA, but I did fly for another airline. The pilots carry docs and the plane carries docs. The plane should have at least 2 checklists and a quick reference handbook, in printed form, in the cockpit. The checklists cover all normal procedures for all phases of flight. The QRH has all of the abnormal checklists. The absolutely vital emergency procedures are printed also in the QRH but the primary source is the pilots memory (things that need to be accomplished ASAP before there is time to consult the book).

What the electronic flight bag (EFB) is going to replace is the junk the pilots carry. My flight bag had 2 2" binders full of nothing but approach plates, a 1" binder with our hub airport approach plates in it, a 1" foldout thing with all of the enroute maps, a 1" binder with the company flight ops (essentially 14 CFR 121 plus whatever opspecs the airline has approval for), a 2" binder with procedures and checklists (serves as backup for the checklists and QRH that the airplane carries), a 2" binder with our collective bargaining agreement in it. Not carried was another 2" binder that were all of the details of the aircraft systems, it was not required to be carries and there just wasnt room for it. The EFB replaces all of that into a tablet form factor.

On a typical flight the only things in that bag that get touched are the high enroute chart I need, the airport diagram and company page for the departure airport and the approach plate, airport diagram and company page for the arrival airport. The checklist used is the laminated one that belongs to the airplane. If there is an abnormal, the QRH belonging to the airplane is consulted (in conjunction with other docs on the airplane: the MEL book and the logbook).

Comment Re:I disagree; Bill is an idiot. (Score 1) 1774

Evolution is scientific. Belief in a creator is religious. Belief in evolution is rational. Each of these statements is true in a way.


No one who understand what science is believes in evolution. Science is not a system of beliefs, it is a system of evidence based reasoning. It is not proper to say "I believe in evolution", but rather "the theory of evolution is the hypothesis best supported by the evidence". In science, nothing can be fact, or definitively proven. We rather conduct experiments to reduce uncertainty in a theory, or to disprove a theory. So, evolution is not scientific, nor is it religious. Evolution and creationism are ideas; two competing hypotheses describing a process. Evolution is supported by the scientific process, while creationism is not supported by scientific evidence. Creationism however is supported by a faith based belief system, and people such as yourself (im assuming) who only know belief systems in turn think that scientists believe in evolution. Perhaps it is not your fault that you are unfamiliar with evidence based reasoning, what skepticism really means, and the scientific method, but that is all the more reason for you to support better science education in our nation's schools.

Comment Re:At least open the specs. (Score 1) 497

If most people don't compile the kernel then I doubt they have the problems you claim. I can't speak for rpm based distros (and perhaps this is why I doubt you, who knows) but I've never had this issue with a debian based distro or gentoo. In debian (i'm a bit out of date here) there was a package you could install (and apt-get update kept it updated) that you would just have to rebuild when you built/installed a new kernel. With gentoo I have a package installed that manages my external modules so I just need to do a 'module-rebuild' and it updates everything to the kernel linked in /usr/src/linux. Perhaps there are more issues for people using distro-built packages, but I can't speak for them either (the only distro-built kernels I've ever used are the ones bundled in installers to get enough of a system installed to build my own kernel). I do recall having some issues 10 or so years ago, but since then, and especially recently, I have had no problems.

The biggest inconvenience I can see is when your binary driver gets upgraded/rebuilt while using X, as then apps trying to use GLX fail with a kernel driver version mismatch, but a quick logout / stop xdm, rmmod nvidia, modprobe nvidia, start xdm, login, fixes that (or just reboot if that is too hard).

Comment Re:At least open the specs. (Score 1) 497

At the end of the day updating a binary driver is a pain in the arse. Every time the kernel changes, the video driver must be updated. The natural inclination for Linux users is to favour AMD or Intel products and forget about NVidia completely.

If you are compiling the kernel and whatever modules you compiled, how hard is it to compile one more module external to the kernel sources?

Chances are if you are using a distro that provides per-built generic kernels for you to use, they also provide a package for the nvidia driver package that takes care of things for you. If you are building the kernel yourself, it really is no pain to use tools like 'cd' and 'make' to build the nvidia driver.

Comment Re:yes but they are claiming that the spin (Score 2) 144

changes gravity.

i.e. they are specifically claiming that 'gravity is different due to the spin'. but the spin is only relevant in that the earth's "geoid" shape is thought to be due to the spin. the spin itself doesnt change how gravity works. at least not that i am aware of. if the earth stopped spinning all of a sudden, but remained a geoid... then the gravity at the poles wouldn't change, nor would the gravity at the equator. the only thing gone would be the centripetal acceleration due to spin. things would 'weigh less' because they lacked centripetal acceleration not because gravity suddenly changed.

an interesting question about your point is this - if you take stuff to the top of a mountain, does it weigh 'more' or 'less' than at sea level?

The spin does cause the Earth to be shaped like an oblate spheroid as you mention but it does alter the gravity you experience as well. The local balance of forces if you are at rest relative to the Earth involves gravitational force and an apparent force (centrifugal) caused by centripetal acceleration. This alters your effective gravity that you experience ever so slightly (ie g_eff = g_newtonian + f_cent, where f is a specific force [units ms-2 or N/kg]) .

Comment Re:Cue Chicken little...... (Score 1) 618

The degree to which we've had a warm dry winter and a hot spring is only represented by 2 years in the last 140 or so. While this pattern may be more common, it usually isn't this amplified. If this year plays out like the two analogs we should have a milder may. In any case I'd look for the trough in the Midwest to end up as a cutoff low over the east and bring a little relief.

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