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Perseverance Rover lands on Mars [video]

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Re: Perseverance Rover lands on Mars [video]

#451

Post by [deleted] »

jessriedel wrote: post #415
_-___________-_ wrote: post #408

Earlier quoted context omitted.

I’m amazed that people still say things like “de-accent” as if there was such a thing as “no accent”. You are asking for a button that makes his French accent more like your own. It’s a separate thing from native vs. non-native speakers - there are plenty of native English speakers with accents that you would also find challenging.

You are reading something into my comment that wasn't there in order to pick a boring fight. There is of course no such thing as no accent a priori, but there is such a thing as "accents understood by (vastly) more people" and "accents closer to the mean accent of native speakers". When I learn Russian, my English accent is not on the same footing as a Muscovite's; the intended notion of "de-accenting" the English ac…

[deleted]

Re: Perseverance Rover lands on Mars [video]

#453

Post by jessriedel »

enriquto wrote: post #427
jessriedel wrote: post #415

Earlier quoted context omitted.

You are reading something into my comment that wasn't there in order to pick a boring fight. There is of course no such thing as no accent a priori, but there is such a thing as "accents understood by (vastly) more people" and "accents closer to the mean accent of native speakers". When I learn Russian, my English accent is not on the same footing as a Muscovite's; the intended notion of "de-accenting" the English ac…

> accents closer to the mean accent of native speakers Notice that, for the case of English, most speakers are not native, by a huge margin! Native English speakers are a biased minority, and with a lot of variation within. Not sure that an "average native" accent is a useful concept at all. I, for one, tend to find most non-native English speakers vastly easier to understand than many native speakers.

> Notice that, for the case of English, most speakers are not native, by a huge margin!

I'm well aware, and this does not rebut any of my points.

> I, for one, tend to find most non-native English speakers vastly easier to understand than many native speakers.

That "many" native speakers in a language of hundreds of millions of speakers are hard to understand does not challenge the claim that a non-native accent brought closer to any native accent, much less the mean native accent, will for the large majority if listeners be easier rather than harder to understand.

Re: Perseverance Rover lands on Mars [video]

#454

Post by thiht »

mulmen wrote: post #419
thiht wrote: post #407

Earlier quoted context omitted.

> I guess 20.5 is nice, 15.5 is cool, 10 is cold, 4.5 is really cold, 26.5 is hot, 32 is really hot and 37.7 is dangerously hot. Or, you know, 20, 15, 5, 30 and 40 instead of the arbitrary decimals you chose to use to prove your point

Sure, you can pick even numbers in either scale that are awkward decimals in the other. I just prefer the ten degree bands of the Fahrenheit scale for these ranges.

> I just prefer the ten degree bands of the Fahrenheit scale for these ranges.

To the identical 5 degrees range of the Celsius scale ?

Re: Perseverance Rover lands on Mars [video]

#455

Post by avz »

gfiorav wrote: post #197
unanswered wrote: post #167

Something I don't understand: when they say "X is 1 minute from happening", does that mean it's really 1 minute from happening or does that mean "in 1 minute we'll receive the signal that X has happened"? Maybe my question makes more sense in the case of "X is happening right now", because then I should either understand "we infer that X should have happened right about now" or "we have confirmed via signal that X ha…

Waiting for the physicist in the room to point out: there is no such thing as simultaneity! :)

In the absence of a physicist, I suppose that a software engineer in the room might do. After all, the counterintuitive consequences of relativity have their counterparts in counterintuitive effects in distributed systems and concurrent programming. In both cases, the core issue that misleads our intuition is the lack of a shared global clock that would impose a total ordering [1] on events/reads/writes/etc. Instead, events in both situations are only ordered partially [2]. In relativity the ordering is determined by the speed of light, in distributed systems the ordering is determined by what messages have been exchanged by two nodes and in concurrent programming reads and writes are ordered by synchronization actions such as lock acquisition and release, memory barriers etc (c.f. the happens-before relationship in JMM [3] and other memory models).

See for example [4] and [5].

[1]: https://en.wikipedia.org/wiki/Total_order

[2]: https://en.wikipedia.org/wiki/Partially_ordered_set

[3]: https://en.wikipedia.org/wiki/Java_memory_model

[4]: https://www.youtube.com/watch?v=UYZIHP120go

[5]: https://www.microsoft.com/en-us/research/publication/time-cl...

Re: Perseverance Rover lands on Mars [video]

#457

Post by mikewarot »

george3d6 wrote: post #434
mikewarot wrote: post #430

Earlier quoted context omitted.

We don't have to be efficient, just small and reliable, no matter how slow... if there were enough small machines to turn out enough materials to build new ones faster than the failure rate, then geometric growth wins, and you can build whatever you want, eventually.

I don't think you're getting my point, consider reading again. There's a fundamental limit you will hit here, you can't just "make it slower" or "make it worst" to lower that limit.

There is a fundamental limit of power... I get that. The Perseverance Mars Rover has one experiment that requires 180 watts of power, (The Oxygen Generator experiment) and it has a 110 watt RTG powering everything. They charge up some lithium batteries during down time, and use them to make up the difference.

In the limit, If something takes 5,000 watts, you could run it for a few minutes/day, with that same RTG, provided you had suitable energy storage.

Perhaps they could gather grains of material, and just sort them, one at a time, only keeping the iron rich material, or use a permanent magnet to gather ferrous material. You could sinter the grains together using a microwave or laser pulse.

The results don't need great quality, just enough tensile and compressive strength to be mechanically stable during additive or subtractive manufacture.

Lots of minds have been thinking about refining metals for a very long time, but they haven't been thinking about doing it on Mars, with limited power, and very far outside the box of normal constraints, like cost.

This is one time capitalism doesn't apply at all... and most solutions assume capitalist incentives and costs, instead of going back to first principles thinking.

Re: Perseverance Rover lands on Mars [video]

#458

Post by unanswered »

randomchars wrote: post #440
unanswered wrote: post #402

Earlier quoted context omitted.

For the same reason referring to anyone with the wrong pronouns is, I would assume. Isn't that offensive? I didn't realize this was up for debate in 2021.

But you're not referring to someone with the wrong pronoun, but using a gender neutral one.

I'm sorry, I honestly don't understand what distinction you're trying to point out. If someone's preferred pronoun is "she", for example, and I refer to her as a "they", then that's the wrong pronoun, isn't it? That's literally the definition of "wrong", at least the definition I understand. The right pronoun is "she" and other pronouns such as "he" and "they" and "it" are, by exclusion, wrong.

But it seems like you're saying there's some kind of complex relation where sometimes people don't get to choose their own pronouns, but other people get to choose which one out of many to use based on convenience. Maybe it would help my understand if you could provide a chart relating the pronouns someone chooses with the pronouns other people are then allowed to use?

Re: Perseverance Rover lands on Mars [video]

#459

Post by danw1979 »

jws wrote: post #344
Azrael3000 wrote: post #55

It's a great achievement with some really interesting work done on the landing algorithms with terrain recognition and it seemed to have worked exceptionally well. Looking forward for the next landing in May of the Chinese rover and all the science these robots will produce. Also, the test of Ingenuity, the helicopter, will be very interesting to watch, that could really pave the way for a different exploration style…

Early starships got me thinking: given the high likelihood of a failed starship landing, and maybe having the ability to send one before fully engineering a payload… What would you ballast a starship with for the practice missions? Useful materials which might survive a RUD and aim for someplace near a likely landing zone? If you crash the parts of a milling machine, a lathe, some tooling, some assorted metals stock,…

Water.

Re: Perseverance Rover lands on Mars [video]

#460

Post by randomchars »

unanswered wrote: post #458
randomchars wrote: post #440

Earlier quoted context omitted.

But you're not referring to someone with the wrong pronoun, but using a gender neutral one.

I'm sorry, I honestly don't understand what distinction you're trying to point out. If someone's preferred pronoun is "she", for example, and I refer to her as a "they", then that's the wrong pronoun, isn't it? That's literally the definition of "wrong", at least the definition I understand. The right pronoun is "she" and other pronouns such as "he" and "they" and "it" are, by exclusion, wrong. But it seems like you'…

> Maybe it would help my understand if you could provide a chart relating the pronouns someone chooses with the pronouns other people are then allowed to use?

I think this is everything wrong with the world currently. Provide you with a chart, so I can justify using gender neutral pronoun?

https://apastyle.apa.org/blog/singular-they

This is barely more than a year old, is it already outdated? I am an asshole for daring to use “they”?

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