sehansen
Joined 18 years ago
Karma
356
Submissions
175
Member since
Mar 23
Mathematician-cum-embedded software engineer. Haskell and Rust, in theory; Python and C++, in practice.
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Comment · 2 days ago
If you're referring to "If the main signal is a (train station's) exit signal ("Ausfahrsignal"), this speed limit applies until the last set of points/switch has been passed by the complete train, after which regular speed is permitted.", I think that means "once you see a normally working signal again, if it's of a specific type (the exit signal), you still have to stay at 40 km/h until you have passed all switches.". As far as I understand the article, Zs1 is mostly intended for very local speed reductions, the kind of speed caution relevant to this discussion sounds more like the Zs7 signal.
Comment · 13 days ago
$1/kWh is ludicrously expensive. It's only hit that level for a handful of hours here in Denmark across the last decade. Most years the most expensive hour doesn't even clear $.70/kWh and it doesn't stay at that level for long. In the past year the spot price only cleared $.50/kWh in 24 individual hours and the longest stretch was 4 hours. Most days the price doesn't even hit $.30/kWh during the evening peak. So there isn't really that much opportunity to make up for the low prices the rest of the time.
Comment · 13 days ago
rrr_oh_man is claiming that wholesale fixed rate electricity is generally cheaper than varible rate domestic electricity. Or that the wholesale-bit is higher order than the variable rate-bit. Not that it's a big issue, bob1029's point doesn't actually care about one situation being wholesale. It's just a somewhat narrow, (in this case) inconsequential, but also valid, nitpick.
Comment · 16 days ago
The reason is people don't want to specify the full set of requirements to that podcast app ahead of time. You can spend your year and $500,000 and then the users will play around with it for ten minutes and then tell you it needs to do this and that as well. And one of those features requires you to go back and make fundamental changes to your architecture making you redo a lot of your subsequent work, including a lot of the formal verification.
So it is harder because there is so much freedom in terms of what features a program can have and what the set of requirements can be. And that's just for getting to version 1.0. Software is expected to change much more than hardware is and if the requirements for version 1.7 can only be met by a severe change to the architecture or an ugly hack, the ugly hack will look very tempting.
Having said all that, I'm not sure I disagree all that much with you. A lot of this could be improved with more big E Engineering in the software world.
One way could be with some kind of professional engineer certification. It should be reasonably easy to get the first time by passing a test on some hard and concrete software engineering principles. But if you are ever found to break them, you lose the license and will have to go through a lot to get it back. That of course only works if companies care about people having this certification.
Which leads (as you mention) to government regulation. As someone who works with medical device software I can see that it actually works. The regulations succeed in forcing us to figure out a reasonably complete set of requirements early, but it is an ordeal. For a recent project we had working prototypes for basically all functionality and still we spent four calendar months doing nothing but requirements before we started developing the actual product.
And yet medical devices still have software bugs. There are 24 software related recalls in the FDA medical device recall database just this year so far: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfRes/res...
Comment · 18 days ago
They exist as aftermarket modifications: https://www.autoexpress.co.uk/citroen/367812/classic-citroen... I've seen them used as foodtrucks for events a few times here in Denmark.
Comment · 18 days ago
Leapmotor sold 19700 cars in total in Europe in the first half of 2026. That's across three models: the T03, C10 and B10. The T03 accounted for half of the sales at 9400, so ~1600 a month. That's quite a bit below the 20th best seller in GPs link, the Volvo EX30 at 3649 sales in August 2026.
Source for Leapmotor sales numbers: https://ievchina.com/brands/leapmotor-stellantis-europe-upda...
Comment · 1 month ago
If they'd done those two things Wordpress would probably have been far less successful. Which certainly is a way of making WP Engine not even want to do what they did. Heck, they would probably not even exist.
Comment · 1 month ago
US and European payers aren't paying for neither R&D nor amortization. They're paying a negotiated price that depends mostly on how much value the drug provides to the patient and the health system. The costs for the producers aren't really a factor.
Comment · 1 month ago
I wonder what they call maize in Egypt then?
According to Kagi Translate, a term for maize that's specific to Egypt is "الذرة الشامية" (al-dhura ash-shāmiyyah) which could be directly translated to "Levantine sorghum". Can anyone with actual knowledge of Egytian Arabic confirm?
Also I had the idea that "Maize" might have come from "Mısır", but etymonline claims it comes from the native (Arawakan) name for the plant: mahiz.
Comment · 2 months ago
800 lbs is 360 kg, but I think you meant 600 lbs per cow. Still seems realistic.
Comment · 2 months ago
No, ARM means "Acorn RISC Machine" and was developed by Acorn Computers, a British computer manufacturer, because the 8-bit MOS 6502 they had based their previous designs on was obsolete, available 16-bit processors "a bit crap"[0] and available 32-bit designs too expensive. So the ARM ISA was developed by a computer manufacturer for use in their own chips in their own products, quite far from an "academic exercise".
0: https://www.youtube.com/watch?v=Hf67JYkUCHQ at 7:35
Comment · 2 months ago
It't not a matter of generations. There are plenty of old mathematicians who are very interested in applications and plenty of young mathematicians who are only interested in generalized abstract nonsense. It's more of a difference in personality that will always be there.
Comment · 3 months ago
Fish and rice isn't synonymous with sushi. Grilled fish, tempura-fried fish and soups with pieces of fish are all popular in Japanese cuisine.
Comment · 3 months ago
I can't speak for the others, but ST has six fabs in Europe and only one in asia. ST's smallest process node is 18 nm and made in their fab in Crolles, France. In any case trying to compete at the cutting edge of process technology seems to be too expensive to be worth it.
Comment · 3 months ago
If "closest star" is Proxima Centauri, we're talking 4.5 light-years. Getting there in 1000 years means an average speed of 0.45% of the speed of light. At that speed less than 0.01 cm of titanium is enough shielding to keep the radiation out according to figure 1c) in my source below. Which makes sense because because this is ~10% of the speed of "normal" alpha radiation which is stopped by just your skin.
"Radiation Hazard of Relativistic Interstellar Flight" by Oleg Semyonov: https://arxiv.org/abs/physics/0610030 via Project Rho: https://projectrho.com/public_html/rocket/slowerlight3.php