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Comment Re:Just to add to this (Score 1) 140

Either way, I wouldn't worry about a 51 day issue. As long as its noted, they can make sure to do a hard restart once a month and life goes on. In fact, I'm not entirely sure the risk of making a fix and possibly introducing another bug would be justified. For that matter, there is absolutely nothing wrong with a periodic hard restart. I'd look at it this way, do you really want airlines doing things that may never have been done during testing? Note that even if you say 51 days should work, well what about 500 days, or 5000 days? Drawing a line somewhere just seems reasonable.

In this instance, switching over to 64-bit ints would let them only need to reboot every 584.9 million years, which seems more reasonable than 51, 500, or 5000 days.

WRT the issue of 64-bit loads/stores not being atomic on 32-bit systems... My initial reaction is that it's a freakin airplane, not a smart toaster -- there's room in the budget to use 64-bit chips.

That said, we are talking about the state of embedded CPUs roughly 20 years ago when development of the 787 started. The 64-bit PowerPC 620 came out in 1997, and can be "configured with either a 64- or 128-bit data bus" (http://www.csit-sun.pub.ro/~cpop/Documentatie_SMP/Motorola_PowerPC/PowerPc/620TSr1.pdf) so it wouldn't have the atomicity issues, but I don't know if it would've been generally suitable for Boeing's needs.

Comment Re:You don't need a graphing calculator (Score 1) 220

You can solve even the most complex engineering tasks with a plain scientific calculator. And tasks assigned to the students shouldn't depend on hardware that is not provided by the school itself. Saying that a graphic calculator is needed for high school is at best an exaggeration and at worst an indication that something is broken in the school system.

High school? I didn't even need a graphing calculator for my college calculus class. I distinctly remember my professor telling the class that graphing calculators weren't allowed on the exam because the problems were designed such that, as long as we left irrational numbers like pi, e, sqrt(2), and such factored out, the correct answer wouldn't involve numbers which were difficult to calculate by hand. IIRC, we could have scientific calculators, but he didn't think they'd really help. His exams were also open-book because something like "if you don't know how to do these problems going into the exam, even with access to the textbook you wouldn't have enough time to figure it out and it'd be a shame to lose points because you made what amounts to a clerical error by misremembering something".

He was right, IMHO, both to make the test doable by hand and to have it be open-book... I think it lets you focus a lot more on why math works the way it does than mechanically applying a formula.

Comment Re:Free App for a smart phone (Score 1) 220

Speaking of tablets and $30, that's how much TI charges for the iPadOS version of their $150 Nspire CX calculators (CAS and Non-CAS versions sold separately for some probably stupid reason). I haven't checked if they make an Android version as well, but I can't think of why they wouldn't.

https://education.ti.com/en/pr...

Comment Re:Whites only VA loans and 1990s racial redlining (Score 1) 422

And if you believe current real estate and lending practices are color blind

In the last fifteen years, I've purchased/refinanced several times. I'm trying to think of any time that I have actually sat down in front of a live person that could tell what color/race/nationality I am when I applied ONLINE for my loans. I did have to sign documents in person, but I was already approved by then.

Google almost certainly knows you color/race/nationality, and I'd be pleasantly surprised if your bank's online application system didn't automatically ask them about you.

Comment Re:Oh wowee (Score 1) 352

"As soon as the cable tension failed, the dogs sprang out, engaged the shaft and Otis only dropped a few inches. Of course, modern systems use different safety devices, but the original Otis one would not work with a maglev drive."

No, but a similar system would. An electro magnet holds the dogs away from the rail, and when the power fails a spring pushes the them against the teeth.

Not that I see anything wrong with the current system...

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