skysight-inc/HackerNews huggingface dataset:
No, because thrust per unit power drops as exhaust velocity increases. You’ll be increasing your power supply and thruster mass far more than any propellant you save. It’s also energy inefficient to use too high of an exhaust velocity.

The mass-optimal exhaust velocity is approximately equal to the square root of (twice the thrusting time times overall power-and-propulsion system specific power times electrical efficiency).

Read more here: https://ocw.mit.edu/courses/aeronautics-and-astronautics/16-...

Assuming no dry mass (spherical cow!), energy optimal Exhaust velocity is equal to the total elapsed mission velocity at any point. If you can’t adjust exhaust velocity, it’s proportional to approximately to 60-65% of the total mission delta-v (off the top of my head).
More discussion of where this energy-optimal exhaust velocity comes from: https://www.youtube.com/watch?v=ogKKjpQvfuM
When you’re just starting, you’re bound to run into a few obstacles along the way. Some of the best programming lessons we’ve learned come from our own mistakes. And some of the best lessons we’ve learned from others — we’ve learned by watching them make mistakes. However, if there’s one person who knows a thing or two about programming, it’s Bill Gates.
And we taxed the planet a little bit as well.
There isn't even a remote equivalence between 'a few doorbells which may, in some cases be used by police' to the 360 information control that the CCP has implemented.

'Surveillance Capitalism' of the Facebook type is equally as mundane: nobody is actually harmed by the fact that Facebook knows a lot about you. Facebook feeds people garbage information, which is arguably harm, but they'd do that anyhow.

If Facebook's was only allowed to collect a fragment of information relative to what they do today - nothing would change. The world wouldn't skip a beat.

Meanwhile, the failure of CCP's information controls, would probably mean regime change within 5 years.
Show HN: Pony – a messenger for mindful correspondence
I absolutely love this stuff. Just to add on here.

I highly recommend checking out the RC2014 project and it's various derivatives. Mr red fedora himself, Alan Cox very active on the mailing list: https://rc2014.co.uk/

Also check out the gigatron: https://gigatron.io/

I don't see this one mentioned much, but I had a lot of fun with this relay computer kit: https://www.tindie.com/products/jhallen/single-board-relay-c...

Someone else already mentioned Ben Eater's youtube channel, but it's worth noting he has two kits. One is a built out of logic gates, the other is 6502 based. https://eater.net/

Moving up the stack a fair bit, the commander X16 has a lot of people patiently awaiting it's arrival: www.commanderx16.com

Finally, there's plenty of stuff on Tindie. Here's one I've come across not too long ago. Note I have no experience with it and this is not an endorsement: https://www.tindie.com/products/glitchwrks/glitch-works-8085...
Piggybacking off this too, if you look at rocket specifications, they’ll often mention the same motor on different stages with a (VAC) behind it. This denotes the different bell shape required to make the motor efficient in vacuum as compared to sea level.

The issue with an aero spike is that the benefits just aren’t there for a multi stage rocket. We do multi stage rockets to balance the needs of high thrust at the launch pad with the need to minimize our final non-payload weight in orbit. Varying the bell design to match flight profile naturally plays well with this approach. If you’re going to ditch parts of your rocket for weight saving during ascent, you might as well tune each stage for the altitude it will actually work at. Motors that need to work at all altitudes are pretty rare, the only ones I can think of are SSTOs in theory, and the space shuttle main engines.

If we could get a falcon 9 with aero spikes it would theoretically be an improvement, but not a huge one. All the gains would be in the edges of various stages where say, the stage 1 motors are flying above their designed altitude. The efficiency gains are there, but they might be completely offset by increased weight, cost, cooling concerns, etc.
> From a business perspective

And that is our fault, to a great extent.

By "we", here I mean citizens of western countries that put up with this bullshit. When one of "our" companies engages in this shameful authoritarian appeasement we should boycott them to oblivion. If we fail to do so, we are enabling this behavior.

There's not much that we can do about human rights abuses in other countries. But there's a lot that we can do in our own countries to local companies that participate or validate the abusers. In that particular case, it would be feasible for Austrian people to stop all Marriott operations on the whole country, with a targeted human-rights campaign.
Scientists mystified as Africa avoids Covid disaster
> An organization going out of business isn't just a case of bad management being eliminated.

Being dispersed. Those people are still around and will go to "work" for someone else
That was 6 years ago, hard to say what remained of that ambitious goal. Also, these guys aren’t with SpaceX anymore.
You say this like engineering is well known for accurate time estimates (especially for design). I haven't seen it. Even very big projects which are well understood overrun all the time in civil engineering, electronics engineering, aerospace engineering, the works.
Thanks. I had a use case in mind where LTO is enabled. Unfortunately the LTO step is quite expensive so relinking does not seem like a viable option. If I find some time I'll give it a try though.
> First, I see the same sort of dysfunctions driven by The Date™ even when no customer promise is involved. Even when no customers are involved.

I believe it, but I've also seen the reverse too. In a situation where no customers are involved, at a non-profit enterprise. When we have a launch date, it helps provide focus on distinguishing what's truly necessary from what's not, and using our development resources responsibly. The launch date needs to be reasonable, and it needs to be understood that it can slip (especially if new requirements show up), but it provided a lot of focus. Having no launch date, sometimes everything but the kitchen sink ends up being thrown in, anything that anyone ever thought was a good idea, and we lose focus on the mission or the end-user, and the project can stretch on forever never being done.
>If there was someone who had more money than them, they'll still lose, and if there wasn't someone with more money, they'll still win.

You're claiming there's no advantage to knowing your opponent's max bid?

I wish all my eBay competitors agreed with you.
In many languages "saint" and "holy" are the same word.
Hello HN!

Pony is a messenger without a send button. When you're finished composing a message, instead of sending it right away, you put it in your outbox. Once a day—in the morning (5:30am), afternoon (12:00pm), or evening (6:30pm)—Pony picks up anything that's in your outbox and delivers any new messages that may have arrived. You can edit a message until it's picked up, move it into drafts, or delete it altogether.

I built Pony because email makes it hard to keep up lasting correspondences with people. I think the main reason for this is because email is dominated by "transactional" communication—time-critical messages that are tied to some particular interaction: order confirmations, password resets, etc. All of these things tend to bury interpersonal correspondence. The same goes for texting and chat platforms: they may be good for keeping in touch with people and for making plans, but messages come and go quickly and they're not really spaces designed for more thoughtful correspondence.

Pony, on the other hand, encourages thoughtful communication and acts as a barrier to anything time-sensitive. It's a highly predictable space and unless you've received a delivery, you know that when you open the app, nothing will have changed. And although Pony encourages you to take your time and not communicate reflexively, it also sets a "micro-deadline" every day, which creates structure that helps keep the correspondence going.

I've started a blog, so if you're interested in reading more: https://www.ponymessenger.com/blog/2021-11-15/humans-are-not.... (RSS is available at https://www.ponymessenger.com/feeds/blog.xml.)

If you like this concept, please sign up and try it out! It's available for iOS, Android, and the web. This is a completely self-funded project. You can contribute inside the iOS app using In-app Purchases or in the web app using Braintree/PayPal. You can also buy me a coffee: https://www.buymeacoffee.com/dmitryminkovsky.
Show HN: SRE Newsletter – Weekly DevOps and Site Reliability Articles
Hello Hacker News,

For about a year, I've been curating a newsletter for DevOps / site reliability engineers from articles posted here, on Reddit, and various other places.

I also took this project as an opportunity to build something in Tailwind and create a simple static site generator (there's a footer link to the GitHub repo).
It's shocking to me how much energy is stored in oil and natural gas (and insolation). We're spoiled with resources! And still so many suffer without the basic necessities of life.
Well I'm not sure what to say. Domains require measure theory if you want to model probabilistic programming languages. Domain theory is part of CS. If you don't know what a domain is, that's kind of on you to read up on.
This is a blind assertion that conflates "caring" with knowing enough to act, and has become less compelling as time goes on. The only way we could unbiasedly poll whether people "care" is if the phone setup process popped up fully-informing Yes/No questions. As it stands, defaults are powerful and people simply do not know how they can control their data being leaked - the average person thinks that GPS satellites track their location.
> cost wipes out their entire profit margin

Comment suggested "calling on public resources to mitigate the attack" implying some sort of government funded program to upgrade old IT.
I think these "money swarms" will learn and be able to coordinate more effectively relatively soon. One of my favourite projects is pooltogether.com, a no-loss lottery where the prize is generated from the interest on the pooled money that is deposited.

I can imagine similar efforts for crowdfunding projects where those that pool their money together don't actually have anything but the interest to lose. Maybe built on top of Alchemix platform? This will certainly be more likely once the transactions fees are lower and people are using layer-2s.
There are efforts to improve these things.

I converted some projects to pyproject.toml (the new standard for defining a project) and between it and the Poetry build/packaging tool it's pretty much solved the packaging nightmare.

There is now a branch of CPython that removes the GIL with significantly better performance in some benchmarks. There is active discussion on the mailing lists about how to get it into mainline.
⍴↑⎕sh 'cal -y' is 36 66. ⍴⎕SE.UCMD'Calendar 2021' is 33 66. Hm.

What system are you on? On Ubuntu, cal -y | wc -l also gives me 36.
https://github.com/seemoo-lab/openhaystack/

As the protocol is already reverse engineered you can actually just DIY a tracker even more unnoticeable than Airtags that generates new keys periodically to trick the Iphones into thinking it's a new Airtag that never saw before.
This is my preferred option as well. Both GitLab and GitHub turn your markdown (and some other formats) files into static pages. They both have web-based editing support, so it is not necessary for a user to know anything about git to contribute. Both can automatically generate a table of contents for a page. And it gives you better versioning than any wiki system.
Yes. I'm convinced the most racist people are those who can't stop talking about race, and that would include a fair amount of self-proclaimed and vocal "anti-racists".
The motive is precisely because it is less lucrative/useful, and surveillance costs money. The 900 number thing is only lucrative because anyone, even a small child, with physical access to a phone has enough agency to bill arbitrary things against that phone number. The dialer (or their guardian) can be forced to repay that bill in some cases, but society obviously lets them incur it.

The way you would delegate surveillance of yourself to another party is to give everything you own to that party in exchange for the ability to live on their property and never interact with the rest of society. Giving up all agency does not look like creating some legal fictions, it looks like withdrawal from society.

I'm not sure I agree with grandparent's assessment, but I don't think these are the strongest arguments against it. I think a better argument would appeal to incidental surveillance: my car has no agency, and nobody is interested in tracking the car for its own sake, but it is surveilled as a way to watch me.
What "large institutions" are good for is preventing norm enforcement.

> Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.

Prohibits the Department of Defense or Department of Education from doing a form of norm enforcement. Prohibits the states of Alabama or California from doing a form of norm enforcement. Good.

Laws prohibiting discrimination on the basis of race/sex/religion/etc.

Prevents the CEOs of Walmart or Apple from doing a form of norm enforcement. Good.

The things done by China or the USSR to people with the wrong ideas. Direct norm enforcement by a large institution. Serious candidate to be the worst thing ever.
I Beat CryptoKittes (2018)
Because it is a truth most of us have accepted without question. Further, it is so agreeable to other facts. Left handed people are evil? But of course, they can attack up in castle staircases! Medeival life was one of constant sword-fighting and war time!

Also I'll admit the first couple arguments in TFA felt weak. I wouldn't be surprised if that colored peoples readings of the rest, or if they jumped to come comment before finishing the rest.
People are voting with their cash, and we love companies that make chinese products. For people the only thing that matters is the price tag.

And companies know that, this is why they poured trillions of dollars of investments in an authoritarian regime. They could had invested in any democratic country that respects human rights with labor and environmental laws, but it would not give them the best bang for their buck.

Companies are ran as Monarchies anyway, so authoritative regimes seem better fit for them.
I‘m from Germany, so I’m close to France but still have an outside perspective and your comment is ridiculous.
>Why do we need an "audience"?

It's not a requirement, especially for those like you. But most people write with the hope that people read their writing. We can debate the importance of this but can't deny the motivation of why people write.

If you don't care about an audience, why spend the effort to maintain an online presence that requires time and money?
Indeed.

> castle specialists have proposed that these buildings were primarily structures intended to be impressive theatrical backdrops for complex ceremonies relating to status and prestige.

You know when the Marines do their rifle drill involving twirling and complex maneuvers with their rifles? That's a complex display of prestige too, but:

a) rifles aren't made for show (although the rifles the Marines use for drill have been permanently disabled)

b) the drill sends a very clear message: "our guys really know how to handle a rifle".

So even if a castle was primarily used for ceremony, it wasn't built as a merely ceremonial device. And the ceremony sends a message: our king is rich, and our defenses are pretty fucking strong. Think twice before laying siege to us.
I was confused by "a noble gas chemically identical to Xenon" for a while because isn't the defining feature of a noble gas that it's chemically inert? Why not just call them Krypton thrusters?
The Ticketing Conundrum
Thank you for the explanation, so the pre-link storage is one of the magical ingredients, maybe mention this as well in the README?

Is this the reason why manyclang (using llvms cmake based build system) can be provided easily, but it would be more difficult for gcc? Or is the object -> binary dependency automatically deduced?
There’s a vast industry of people supplying services to cash out illicit wire transfers. The complexity depends on the amount.

For individual amounts below 20-30k (craigslist scams, etc) you’ll be looking at personal bank accounts, usually created with fake IDs, but also sometimes using victims of various hiring scams. The fees you pay will largely depend on the country around 50% for US accounts, 20% or so for EU/UK accounts.

For slightly bigger amounts (fancier craigslist scams, BEC) up to a quarter million or so, you’ll see lots of pretty plain corporate accounts. The fees remain pretty much the same.

For the huge amounts (pretty much just BEC) like 5 million usd or more it starts to get complicated. At this point you begin to see offshore accounts for the first time, Hong Kong or just straight up PRC. But anything is possible, even US accounts can be arranged. Often someone will take over an existing business and their bank accounts, and then quickly run millions through them. At this level it’s hard to give an estimate on the fees, they are negotiable.
The most amazing part is that the participants for at least an hour all thought they won. They were celebrating in a Twitter Space. I popped in for a few minutes, heard many people talk about how they were "literally shaking" from the excitement, and really playing up the significance of the constitution being "the first act of decentralization from English rule" and 2022 being "the year of the DAO".

Nobody had the heart to tell him that the constitution was not the declaration of independence.

But it turns out the "inner circle" running this Twitter space, who all had very official looking Lions and Apes as their avatars, was so far removed from the actual inner circle that they had no idea what really happened at the auction and instead were just LARPing as being insiders.

I am not anti-crypto, but most of the crypto culture should probably be burnt to the ground.
So almost literally how iOS and Android notifications work except I guess jointly owned and operated by by Google and Apple? Because public services like this are necessarily funded and operated by the companies that have a financial interest in them existing.
Nextcloud is more complex than most PHP apps.
Randall Munroe needs to update that one for Python3

$ python3
Python 3.8.10 (default, Sep 28 2021, 16:10:42)
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> print "Hello, world!"
File "<stdin>", line 1
print "Hello, world!"
^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print("Hello, world!")?
Decomposing projects before you even start coding is everything.

The bigger the project, the more likely it is that some small thing - something in the original spec, maybe, or more likely, an unforeseen interaction of its pieces - will be missed and will take an inordinate amount of time to deal with. All it takes is one of these to thwart the entire estimate.
Just put that "project delivered ahead of time" to your CV and go find the raise elsewhere. That's how the industry works for devs anyway.
#3 is the exact case where you also want to just pin everything. For an end-user desktop application, you ship a properly tested bundle, instead of trying to support all the different versions; as the end-user (unlike a developer using a lib on their own machine) should not ever have to interpret compatibility issues and should get a package that's been tested to work as a whole.

If a distro ships python 3.6 and the app wants to use 3.7, then the end result must include python 3.7 as well, either by distro being capable of having both versions at the same time or the app needs to ignore the distro-python and ship its own version in the package.
I'm too lazy to look at the JS, do you happen to know what algorithm those tools use? Is it just naive maximum likelihood or something more interesting?
Control flag, AI-Driven Detection Of Bugs, v1.0 Full support for C released
The Fry Universe: 3D Modeling of various fry shapes to illuminate fry preference
This hits the nail on the head. All of my friends who are in the process of becoming journalists have to spend tons of time working unpaid shitty internships just to get a low paying bottom rung job.

The only people I know who are even able to get jobs like this either have parents in the industry or have rich parents, often both.

This is also true for the humanities in academia writ large - most of the people I know getting a PhD in the humanities have rich parents.
Nice to see Dan Brown in our midst.
Adults who microdose psychedelics report lower levels of depression and anxiety [pdf]
Aren't ~70% of humans right hand dominant? Maybe the local builder just built what the customer wanted.
Suicide Prevention: The Honorably Ambivalent – Mag’s Monthly
Smallpox is actually dangerous, and the smallpox vaccine is like 200 years old. Not even 1% of people would refuse that vaccine in that scenario.
Vaccinedeaths.com
I realize this comment is probably tongue-in-cheek, but if we take it at face value, I think it’s failing to consider that the logical conclusion of this argument is to not write programs in the first place.
The number of deaths is indeed low.

How's the number of traffic-related injuries?
Yes, you’re quite right! Thank you again, I must remember to use pry more.

With ruby 3.1 I think we’re getting a new default debug.rb gem.

It will be interesting to see if pry or the beat ideas from pry can be integrated with that.
"Quince Cheese" sounds awesome :-)
I thought it was pretty well established. The author wasn't saying that people who value individualism don't value privacy, rather that the pursuit of individual over community values caused an erosion of privacy (regardless of anyone's intentions).

The argument was that getting rid of the informal, localized social norm enforcement mechanisms (your nosy neighbors, a meddlesome priest, etc) that used to prevent people from fully expressing their individuality created a vaccuum that was filled by surveillance.

Your nosy neighbor used to judge you for things we don't think ought to be judged anymore, but they also noticed if you were drinking too much or stopped going to work because your mental health was declining. Since society still needs to work and not drive drunk, surveillance by states and large corporations has stepped in to fill the gap.

So, according to the author, the individualistic ethos brought us to the point where some machine will silently judge me for this post.
Is something like spinlaunch (centrifugal force) even better than a hydrogen gun (linear acceleration) from the perspective of g forces? For example Quicklaunch (6 km/s speed, 1100 m barrel) would require ~1700g of acceleration. Spinlaunch appears to be significantly more demanding while providing even smaller initial velocity. Even if it's just cargo applications, surely there's still a difference between 1000g and 10000g.
Collectively, the West is much more powerful than China, but nobody in the West is nearly as powerful as Xi.

In that fragmentation, he can gain considerable leverage like this, without even having to say a word.

One thing that might help even larger businesses is for government to pass legislation banning this kind of activity, i.e. making judgements on who can attend or not, or at very least, passing it off to the local officials.

That way, Marriott can say 'Sorry Xi, our hands our tied, we had to let them have their conference, take it up with Biden or Merkel'.