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World Airports Voronoi

jasondavies.com

61–70 of 90 posts

Re: World Airports Voronoi

#61

@shitsandwich just in case you see this, you are hellbanned.

I check someone's comment history before alerting them - the previous comments by that handle were all trolls. Hellbanning is meant to block these users; no point telling them.

Re: World Airports Voronoi

#62
This is really cool. If I remember right international passenger flight regulations insist that there be atleast one airport that can handle your class of aircraft within 180 minutes of flying time at one engine operative speeds at all times. If we assume a passenger jet flies at roughly 0.8 Mach or ~960 kph, and one-engine operative speed is roughly 40% of that or ~384 KPH. That means an airport needs to be within a circle of radius 1152 kms. That's an area of ~4.16M km-squared. Simplifying that all airports can handle all passenger jets, not one of those voronoi cells can have an area greater than 4.16M km-squared.

Is there an easy way to calculate the area of each cell?

Did I mention this is really cool!!

Re: World Airports Voronoi

#64
post #62

This is really cool. If I remember right international passenger flight regulations insist that there be atleast one airport that can handle your class of aircraft within 180 minutes of flying time at one engine operative speeds at all times. If we assume a passenger jet flies at roughly 0.8 Mach or ~960 kph, and one-engine operative speed is roughly 40% of that or ~384 KPH. That means an airport needs to be within a…

The regulations you're thinking of are ETOPS (Extended-range Twin-engine Operational Performance Standards or, alternatively, Engines Turn or Passengers Swim).

Re: World Airports Voronoi

#65
post #5

Earlier quoted context omitted.

https://en.wikipedia.org/wiki/Shuttle_Down . The upgrade of the runway to support the Shuttle started in May 1986 ( https://news.google.com/newspapers?nid=2245&dat=19860423&id=... ) and ended by August 1987 ( https://news.google.com/newspapers?nid=860&dat=19870817&id=Y... ).

"In addition, astronauts now carry passports and other documents, including traveller's cheques, in case of emergency landings."

Note the '[citation needed]' - I think that text comes from the publisher's comments in the book. If so, well, publishers aren't known to be scrupulously honest.

Re: World Airports Voronoi

#66
post #64
post #62

This is really cool. If I remember right international passenger flight regulations insist that there be atleast one airport that can handle your class of aircraft within 180 minutes of flying time at one engine operative speeds at all times. If we assume a passenger jet flies at roughly 0.8 Mach or ~960 kph, and one-engine operative speed is roughly 40% of that or ~384 KPH. That means an airport needs to be within a…

The regulations you're thinking of are ETOPS (Extended-range Twin-engine Operational Performance Standards or, alternatively, Engines Turn or Passengers Swim).

And those only pertain when you fly out of reach of a suitable airport to land on, in the case of flying on one engine, in still air for > 60 minutes.

Re: World Airports Voronoi

#67
post #6

This runs slower on my computer than MGSV in ultra settings running on 4k resolution.

Completely unusable on my iPad Air. Damn. It's amazing how fast computers are. And it's amazing how slow we make them with layers and layers of cruft built atop more layers and layers of cruft.

The difference is that all you have to do to view this is punch a URL into a browser, on virtually any computer in any form factor, and it's on your screen instantly with absolutely zero setup. Of course there's a performance cost to this incredible convenience.

Imagine if the author had instead used, say, DirectX and C++ and only bothered compiling it for his own platform. Not only would it be nearly impossible for this to have reached the same audience so quickly, but it likely would have taken the author longer to make as well because JavaScript + D3.js are uniquely suited towards rapidly making these sorts of prototypes.

Re: World Airports Voronoi

#68
post #8

I thought that a voronoi partition is not possible with only straight lines on a non-euclidean space like that; this leaves me confused.

You are in fact correct that the boundaries of the Voronoi cells on a non-Euclidean manifold need not be geodesics. Consider for instance the manifold which is a cone with a circular base, and let the sample points be the apex of the cone and the center of the base. The boundary of the two cells thus produced will be a circle parallel to the base, which is not a geodesic on the cone.
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