PorkrollPosadist

joined 4 years ago
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[–] [email protected] 4 points 2 hours ago* (last edited 1 hour ago)

The exhaust pattern from a rocket / jet engine changes in relation to atmospheric pressure. At low altitude / about one atmosphere, the exhaust remains fairly linear, like the condensation trail from an airliner passing overhead. At very high altitude / approaching vacuum, the exhaust gas continues to expand long after it has left the motor, producing more of a cone shape than a line. This is related to the reason why rocket motors designed for use in the vacuum of space have large parabolic nozzles, vs. the motors used for lower altitude booster stages which have much shorter nozzles (though I don't think missile tech goes to the same extremes seen in space programs, because these large nozzles have other drawbacks, like increased mass, increased size, lower durability, and lower performance in atmosphere).

These large conical plumes indicate a loss of efficiency. When possible, you would want to either increase the size of the nozzle, or decrease the amount of pressure coming out of the motor, but if your objective is to go as fast as possible (vs. going as far as possible), you're not turning down the pressure, and the shape of the nozzle will always be a design compromise. It cannot be at peak performance across the whole range of atmospheric pressures, and missiles will apply the majority of their thrust in atmosphere.

(image stolen from a hobby rocket manual lmao)

[–] [email protected] 35 points 6 hours ago* (last edited 6 hours ago)

I think Israel blew their load too early. The months-long deployment of military assets makes it clear they (the "West," collectively) planned to make a move on Iran, but they weren't fully prepared yet. All this concent manufacturing was supposed happen before the missiles started flying, but Israel wanted most of all to ensure nobody got cold feet and executed one of their signature moves - killing the negotiators - prematurely, to ensure they got their way. The media in Washington is in lockstep support for immediate war, but I have to imagine some high ranking members of the administration are genuinely pissed at Netenyahu and want him to sweat a bit, even if they are fully devoted to Israel and will proceed with the plan. They might just be sticking to their original schedule.

I think Trump personally does not mind letting Israel take the heat here. If state of the art American aircraft start getting blown out of the sky, he doesn't have to take responsibility for it, while if the Iranians captured USAF pilots and held them hostage like they claim to have an Israeli pilot, it would be deeply humiliating.

[–] [email protected] 18 points 21 hours ago* (last edited 21 hours ago)

I feel like Russia-Ukraine hit different. The lockstep imperialist messaging was similar, but they had a much more credible narrative. They could get up there day after day and grandstand about how Russia initiated a war of aggression and invaded a sovereign country, and that they were fighting for the underdog. Of course, the history and context which led to the conflict make things more complicated, but they had solid branding.

This is substantially different. Here you Israel, which has been completely out of control, bombing and seizing territory in Lebanon, bombing and seizing territory in Syria, bombing Yemen, bombing Iraq, carrying out an unlimited genocide in Gaza for nearly two years, finally bombing Iran completely unprovoked during ongoing diplomatic negotiations. They bit off more than they can chew, and instead of accepting the outcome of Israel being humbled just a little bit, the only option is total war on the victim to protect Israel's ego. It isn't even a matter of Iranian troops marching through "Israeli" cities and seizing (liberating) territory. It is a tit-for tat "you launched a decapitation strike on our military out of fucking nowhere, we are blowing up a number of your military buildings in kind." This is a shit sandwich through and through. Instead being able to brand American imperial power as a charitable act in defense of democracy and international law, the naked bloodlust of the American media is revealed like an inside-out skin suit.

(this post would have over a dozen scare quotes in it, but I decided this short parenthetical remark would make it more readable)

[–] [email protected] 28 points 2 days ago

Probably also the reason "nuclear" options like closing the Straight of Hormuz or attacking oil infrastructure of the Gulf monarchies have been reserved.

[–] [email protected] 28 points 2 days ago

Real dick in a blender hours.

[–] [email protected] 28 points 3 days ago (1 children)

The Israeli army might actually have more generals than Iran has missiles.

[–] [email protected] 59 points 4 days ago (2 children)

Years of Lead Paint

[–] [email protected] 6 points 4 days ago

It may be Civil War-adjacent, but there is John Brown. john-brown

[–] [email protected] 18 points 5 days ago

Becoming a Suckless guy but for missile defense systems.

[–] [email protected] 43 points 5 days ago (1 children)

Using the Pentagon Dominos Pizza activity loophole to announce the liquor store was a mob scene today.

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submitted 1 week ago* (last edited 1 week ago) by [email protected] to c/[email protected]
 

Retweeted by Majority Report

Insurrection is GOOD, fucking morons. Months before this picture was taken, demonstrators had surrounded the White House and were ripping away the barricades set up by the capital security forces. It was based as hell and Trump was ushered to hide in his bunker as a result. The problem with J6 was not the method, or the utter disrespect for the Capitol. It was that they were reactionary freaks. Look at them. They're waving a SOUTH VIETNAM flag! Fucking losers. uncle-ho-2

link

 

https://en.wikipedia.org/wiki/Kosmos_482

Kosmos 482 (Russian: "Космос 482" meaning Cosmos 482), launched 31 March 1972, at 04:02:33 UTC, was an attempted Soviet Venus probe which failed to escape low Earth orbit. It is expected to crash back to Earth sometime around early 9 to 10 May 2025.[1][2] Its landing module, which weighs 495 kilograms (1,091 lb),[3] is highly likely to reach the surface of Earth in one piece as it was designed to withstand 300 g of acceleration and 100 atmospheres of pressure.

 

Die mad, loser.

 

A changelog written as if time went backwards, reporting all the features being removed from Emacs

 

I was trying to process a database of star data and export it to a texture which I could then use in a sky shader (instead of pre-rendering a cube map like a rational person), but Pillow does not seem to work well with color channels greater than 8 bits, so I thought... what if I just inline hundreds of kilobytes of data in an array? This isn't variable data. It doesn't need to be a uniform. It is not like the game is going to run long enough for these stars to move.

I have a feeling this won't work, but I want to see if it will almost work. The shader compiles and runs, though it is not yet processing this data. It takes a pretty long time to compile though. Every time I type in the Godot shader editor the CPU cooling fans spin up to maximum. The editor also seems to really hate text files where lines are 340,000 columns long

Update: It took about five minutes to render one frame, and then Godot crashed.

169
submitted 6 months ago* (last edited 6 months ago) by [email protected] to c/[email protected]
 

Hello comrades. In the interest of upholding our code of conduct - specifically, rule 1 (providing a friendly, safe and welcoming environment for all) - we felt it appropriate to make a statement regarding the lionization of Luigi Mangione, the alleged United Healthcare CEO shooter, also known as "The Adjuster."

In the day or so since the alleged shooter's identity became known to the public, the whole world has had the chance to dig though his personal social media accounts and attempt to decipher his political ideology and motives. What we have learned may shock you. He is not one of us. He is a "typical" American with largely incoherent, and in many cases reactionary politics. For the most part, what is remarkable about the man himself is that he chose to take out his anger on a genuine enemy of the proletariat, instead of an elementary school.

This is a situation where the art must be separated from the artist. We do not condemn the attack, but as a role model, Luigi Mangione falls short. We do not expect perfection from revolutionary figures either, but we expect a modicum of revolutionary discipline. We expect them not simply to identify an unpopular element of society hitler-detector , but to clearly illuminate the causes of oppression and the means by which they are overcome. When we canonize revolutionary figures, we are holding them up as an example to be followed.

This is where things come back to rule 1. Mangione has a long social media history bearing a spectrum of reactionary viewpoints, and interacting positively with many powerful reactionary figures. While some commenters have referred to this as "nothing malicious," by lionizing this man we effectively deem this behavior acceptable, or at the very least, safe to ignore. This is the type of tailism which opens the door to making a space unsafe for marginalized people.

We're going to be more strict on moderating posts which do little more than lionize the shooter. There is plenty to be said about the unfolding events, the remarkably positive public reaction, how public reactions to "propaganda of the deed" may have changed since the historical epoch of its conception (and how the strategic hazards might not have), and many other aspects of the news without canonizing this man specifically. We can still dance on the graves of our enemies and celebrate their rediscovered fear and vulnerability without the vulgar revisionism needed to pretend this man is some sort of example of Marxist or Anarchist practice.

 

Perhaps one of the more surprising changes in the 6.12-rc4 development kernel was the removal of several entries from the kernel's MAINTAINERS file. The patch performing the removal was sent (by Greg Kroah-Hartman) only to the [email protected] mailing list; the change was included in a char-misc drivers pull request with no particular mention.

The explanation for the removal is simply ""various compliance requirements"". Given that the developers involved all appear to be of Russian origin, it is not too hard to imagine what sort of compliance is involved here. There has, however, been no public posting of the policy that required the removal of these entries.

An early comment likely pins down the prevailing institutional pressures leading to this decision

What's the deal with an international project adhering to what is obviously a decision of the US government?

Hint: The Linux Foundation (which notably employs Greg KH and Torvalds, and provides a lot of the legal and other infrastructure for this "international project") is based in the US, and therefore has to follow US laws.

This is pretty fucked up. Like, we might see the kernel forked in the coming months/years.

See also: Phoronix: Linus Torvalds Comments On The Russian Linux Maintainers Being Delisted

 
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submitted 8 months ago* (last edited 8 months ago) by [email protected] to c/[email protected]
 

After 21 years of development, FreeCAD 1.0 is rapidly approaching. The project has entered a release-candidate phase, where testing versions are released for last-minute evaluation and bug discovery before finalization. This post links to the RC1 announcement (the big news), but a second second-plane release candidate has been published since then.

15
Caca Labs (caca.zoy.org)
submitted 9 months ago* (last edited 9 months ago) by [email protected] to c/[email protected]
 

If you've been running Linux for a while, you may have seen libcaca get pulled in as a dependency here or there and thought it had a funny name. It is a library for manipulating text graphics ("ASCII Art," though it has full UTF-8 support). I visited their website this morning and thought it was remarkably quaint.

Also got a big laugh out of "Terror on the Desktop."

spoilerhot-babe was a CPU usage monitor for X11 displays which embedded in your desktop in a similar fashion to conkey. It featured an anime waifu who would get increasingly naked the more busy your computer was. A utility which now lives in the trash heap of computer history.

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I did a PC case mod (hexbear.net)
submitted 9 months ago* (last edited 9 months ago) by [email protected] to c/[email protected]
 

Designed in FreeCAD and printed on a custom Ender-3 V2. A couple more details / photos in the Mastodon thread.

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