azernik

52 ms·

631.
by azernik 6y ago
It can be a success if you fulfill your strategic objectives (see e.g. the American units that were nearly completely destroyed in the early weeks of the Korean War buying time for troops to arrive at the Pusan Perimeter). In this case, t
632.
by azernik 6y ago
The UK didn't fall after losing a good chunk of their army and almost all of their heavy equipment in the Battle of France. It was still a defeat. In the Thermopylae case, they failed at their intended objective (defeat the Persian arm
633.
by azernik 6y ago
The problem with people's adulation for this mythical Sparta is that it includes ideas about causation (they were strong because they were monomaniacally focused on war!) and morality (military strength is a more important merit for a
634.
by azernik 6y ago
It produced external myths about a warrior culture. Thank Athenian and Roman authors, not Sparta itself, whose reality was only tangentially related to those myths.
635.
by azernik 6y ago
Note that the celebration of Sparta goes all the way back to their contemporaries in the rest of Greece. Generally, like today, their image was used as a rhetorical cudgel to beat your opponents with; usually for being too democratic, not &
636.
by azernik 6y ago
"Netflix Original" anime (and many other foreign media, e.g. K-Dramas) aren't produced by Netflix; Netflix just throws money at them to get exclusive US distribution rights. There's competition here, but it's with o
637.
by azernik 6y ago
Price discrimination is a hard problem! There's a conflict between soaking your customers for as much as they're willing to pay, and making your product accessible to customers that won't pay that much. Finding a feature set
638.
by azernik 6y ago
The original article proposed different sized goals for different leagues.
639.
by azernik 6y ago
Even with zero influx, at current estimated usage it should last about 100K years
640.
by azernik 6y ago
"The protocol has been criticized for omitting any mention of prewarming the pot.[6] Ireland was the only country to object, and objected on technical grounds.[7]"
641.
by azernik 6y ago
As far as I can tell that framing is probably for crowd appeal. The real breakthrough here is the availability of high-magnetic-field superconductors, which push the size requirements for break-even down a lot and so put construction cost
642.
by azernik 6y ago
They will run coolant through the reactor walls, and send that coolant to a steam generator.
643.
by azernik 6y ago
> To get confinement to last longer the magnetic field concentration needs to increase. Which is what the new project will do - using a classic tokamak with the much higher field magnets that can be built with high-field superconductors.
644.
by azernik 6y ago
The parameters that go into the efficiency/gain of a power plant are well known: gain goes up as radius to the power of 1.3, and magnetic field strength to the fourth power . ITER was conceived in an era of much lower-field supercondu
645.
by azernik 6y ago
There are lots of more conventional footguns in JS, though - everything about the Date object/class, for example.
646.
Europeans get ‘right to repair’ for some electrical goods(independent.co.uk)
94 points by azernik 6y ago|77 comments
647.
by azernik 6y ago
Ah - yup, was confusing the plan with something that had happened already. Apparently the rover will drive to a better takeoff site, then go through that process. But the helicopter will, indeed, be expected to survive on its own, not eve
648.
by azernik 6y ago
And even if they did, no one remembers that well the things they did decades ago.
649.
by azernik 6y ago
A long write-up of an equivalent for the F-1 engine is here: https://arstechnica.com/science/2013/04/how-nasa-brought-the... The analogy to out-of-date software documentation is very apt. As problems or ineff
650.
by azernik 6y ago
A related story: One of the proposals for future upgrades to SLS (ugh) was liquid-fueled boosters using new-build F-1 engines (i.e. Saturn V main engines). Unfortunately, the specs were not complete; not only was lots of stuff different in
651.
by azernik 6y ago
The ground controllers themselves don't know precisely. I suspect they'll have more precise timelines in the last week before flight, but that's just a wild guess on my part.
652.
by azernik 6y ago
Right after landing, Perseverance put Ingenuity down on the ground and drove off to give some separation. The winds and sand aren't mechanically very strong - the Martian atmosphere isn't dense enough to transmit much force even a
653.
by azernik 6y ago
Data comes from Perseverance through two channels: * A low-bandwidth direct link to Earth (160bps-800bps depending on receiver dish- no, that's not a typo) * A high-bandwidth link to orbiting satellites, which then forward traffic to E
654.
by azernik 6y ago
Once it's been sent to Earth, they drop it. Curiosity's main computer had a flash drive of 2GB, and each of the big cameras had an 8GB flash drive on board. I doubt Perseverance is much changed from that; the main computer is IIRC
655.
by azernik 6y ago
The helicopter hasn't flown yet - they put it down on the ground, and they're going to run it through a lot of remote checks before flying it. IIRC it's gonna be a month or two before first flight.
656.
by azernik 6y ago
> If this were some custom format rather than json and the parser still used sscanf, the bug would still happen. So I think json is somewhat orthogonal to the matter. What's the point of using standard formats if you're not tak
657.
by azernik 6y ago
See footnote 6 in the original article: "That’s the original S/390, mind you, not the 64-bit “s390x” (also known as z/Architecture). Think about your own C projects for a minute: are you willing to bet that they perform corre
658.
by azernik 6y ago
Very likely. In ground testing, even in a thin Mars-equivalent atmosphere, that thing is LOUD.
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by azernik 6y ago
This apparently also introduces some serious control issues - with propellers that long and massive, there's substantial lag between control inputs and flight changes. In ground tests in pressure chambers, it was difficult-to-impossibl
660.
by azernik 6y ago
Yup - lower gravity helps, but by much less than the orders of magnitude by which the thin atmosphere hinders.

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