perestroika

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[–] perestroika@slrpnk.net 3 points 1 week ago* (last edited 1 week ago) (2 children)

That's some quite chilling reading.

People never got information about what mistake or malfunction took their relatives' lives, but the leaked files draw a pattern of Teslas making erratic maneuvers when self-driving.

Also, there's a pattern that crashed Tesla drivers tend to burn to death without passers-by being able to help them - because passers-by depend on opening doors using their handle, not pulling people out through windows or cutting through structures with hydraulic scizzors. By the time firefighters arrive, the person is dead and the fire too hot to apprach.

I would never buy a Tesla anyway, since I like utmost simplicity in vehicles.

But the Tesla battery seems like a special invitation for trouble to me - a ridiculously high number of small lithium ion cells. Unless your production is 100% reliable, that's not a manageable configuration. A low number of large cells in manageable. Also, it seems that their battery is very likely to short in a crash. A low number of large cells have more limited options for shorting and more chances of the single series connection breaking. As soon as you have parallel cells, you're asking for trouble.

[–] perestroika@slrpnk.net 2 points 1 week ago

I also tried.

Can't access the .se site currently (I've sometimes been able to). A mirror site which responded didn't have the PDF. So I can't form an opinion about the subject currently. :)

In my experience, linking to Sci-Hub is like that... like a lottery.

[–] perestroika@slrpnk.net 17 points 1 week ago* (last edited 1 week ago)

As a person who develops drones, and who has already read the article about a week ago, and given a review of it in another place:

The author's unit was quite obviously supplied with crappy drones, his description hints of many recognizable issues. Their takeoff failure rate would be considered unacceptable in some circles. Their detonation failure rate hints of sappers erring on the side of caution (sappers want to go home alive). These problems can be solved with factory made munitions and decent quality assurance.

Some of his complaints are organizational. Lacking bomber drones, they wasted FPV drones to destroy stationary / abandoned / disabled vehicles. This is not a tech issue, but an organizational issue.

He's correct to point out that heavily loaded quadcopters won't safely take off in adverse weather. I must remind that a catapult launched UAV plane will reliably take off in adverse weather, exceed quadcopters in range and payload capacity, so we can guess that planes taking off from launch tubes will gradually replace quadcopters taking off from grass.

He's correct to point out that once you go below direct visibility, your 5.8 GHz video link will break. There's at least 3 solutions around this: an airborne repeater, fiber optic cable and bombing the target from altitude. All 3 solutions are already widespread.

He mentions lack of GPS, compass, inertial navigation and pilots getting lost. This is true, GPS is suppressed on the front and will likely stay suppressed, some drones are cheap and don't provide the pilot with obvious and simple navigational aids (they should) and some pilots do get lost when navigating (this is unavoidable, but can be reduced).

He mentions need for long training. This is the current reality, but not the reality of a tailor-made combat drone system. Today, people are fighting a war with civilian sports supplies. That's why pilot training is important to overcome difficulties. In a few years, you can give a ready-made drone system (in a sealed container, with a factory-made warhead) to a random guy or girl from a street in the middle of a storm, and he or she can shoot down a combat helicopter from 10 kilometers distance with it. Just liking firing an NLAW can be learned in 5 minutes (but not mastered, of course), firing a drone will be possible with 5 minutes of instruction in the near future.

[–] perestroika@slrpnk.net 3 points 1 week ago* (last edited 1 week ago)

Not "back to Syria" but "how to get him back from Syria, where he has presumably fled", if you read the article.

[–] perestroika@slrpnk.net 33 points 1 week ago* (last edited 1 week ago) (1 children)

Going by this article...

https://nltimes.nl/2025/06/30/brothers-still-deny-involvement-18-year-old-sisters-honor-killing

...I would speculate that by sending the letter, Khaled al-Najjar attempts to free his sons of complicity in the crime. Whether they are or aren't complicit, is for the court to determine. Getting the man back from Syria would be a priority for the court, but given the situation in Syria, this might be difficult to arrange.

The court seems to consider the brothers either plausibly complicit or a flight risk and decided not to free them on bail.

The brothers’ lawyers requested that they be released from pre-trial custody. They have been detained for almost 13 months. Both insist that they “had nothing to do” with their sister’s murder. But the court ruled that they’ll stay in custody until the next hearing in September.

...and...

But the OM [prosecution] believes that the father enlisted his sons to pick Ryan up, drive her to a remote location, and throw her weighted body into the water. According to the OM, the three men killed Ryan because she behaved too Western and “shamed” her family.

[–] perestroika@slrpnk.net 1 points 1 week ago* (last edited 1 week ago) (1 children)

This does not seem likely.

There has to exist a reason for Wang Yi opening some cards, but Kaja Kallas is not that reason. Wang Yi does not make uncoordinated statements and Kaja Kallas isn't attempting to achieve that either.

Somewhere in the CCP political bureau, it was agreed that Wang Yi will send this public signal.

The reason could be something in China, something in Russia, something in Europe or in the US. What is the reason? I don't know currently, but I'm not the only one solving this puzzle.

[–] perestroika@slrpnk.net 26 points 2 weeks ago (2 children)

As a side note: there is speculation that China may be approaching a change of leader due to Xi experiencing health issues (not a change of leadership in the wider sense - the collegial system of the CCP is considered to be functioning).

Thus, it may be impossible for the Chinese foreign minister to be fully confident of what China's policy will be in the future.

Obviously, China views it as unacceptable for Russia (its ally and soon enough, practically its vassal) to all-out lose. (The easiest way to not lose, of course, is not starting a war, but that train is long gone and behind the hills.)

Prolonging the war does not eliminate this risk well, however - exhaustion could spread in Russian society and morale could collapse despite the state spewing its propaganda, or the economy could collapse. So, simply propping up Russia by letting them buy the goods they shouldn't be getting is not a very elegant solution. Direct interference on behalf of Russia would lead to open hostility with the EU, which is currently ambivalent about China.

What remains is nudging Russia to negotiate. But Putin is hard-headed and only willing to negotiate Ukraine's surrender, on terms which Ukrainians will laugh out of the door.

As for the US being able to focus on China, well I guess they're a bit concerned about it, but given the mental and organizational capability of the current US leadership, I don't think Chinese analysts are particularly worried.

[–] perestroika@slrpnk.net 3 points 2 weeks ago

If implemented like moped battery swapping on Taiwan, things might work. If everyone designs their own unique solution, nope. :)

[–] perestroika@slrpnk.net 9 points 2 weeks ago* (last edited 2 weeks ago)

It's like with earthquakes. At first, when nobody knows jack s**t, they tell you 10 people died.

When the statistics come home, often enough, an initial 10 turns into 10 000.

With a heat wave spanning half a continent and breaking records, the typical mortality to expect (basing on experience) is at least 1000 people (some of them old and about to go anyway, but pushed over the edge by heat).

[–] perestroika@slrpnk.net 2 points 2 weeks ago (1 children)

Possibly, reverse motivation - the training goal of such an agent would not be nice and smooth output, but shooting down misinformation.

But I have serious doubts about whether all of that is feasible, given the computational cost of running large language models.

[–] perestroika@slrpnk.net 38 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

Speculation on my part:

Patriot stocks may have been really reduced - by defending Israel during Netanyahu's adventure against Iran (it could have been smarter to tell Netanyahu not to start).

There is no reason to think that stocks of other weapons (e.g. air to ground missiles, glide bomb units for F-16) have suddenly gone really low. In fact, there is probably a f**kton of them.

Consequently, I suspect that Trump and Putin have made a deal they failed to disclose: Putin promised to refrain from helping Iran (it was an easy promise, he was really low on supplies). Trump promised in return to refrain from helping Ukraine, which he could have easily helped. At best, he got conned, at worst he got to do what he already wanted.

I would advise journalists to ask around: "has the US DoD been ordered to alter criteria for determining what is sufficient supply?" If yes, we're looking at an excuse. If no, we're looking at inability.

Both are bad, but inability can be corrected with honest admission and action, Ukraine has a bit of money from other allies to actually buy some US weapons, although they are rushing to make more domestically.

If it's not inability but an undercarpet deal, then corrections are bit harder to achieve.

 

Living off grid often correlates with poorly accessible locations - because that's where the infrastructure is not.

On certain latitudes, especially near bodies of water, especially in remote locations - do not ask who the snow comes for - it always comes for you (and with a grudge). So, what ya gonna do?

Over here, a tractor being incomplete (it is great folly to go into winter with an incomplete tractor), snow is handled by an electric microcar. Since the microcar is made of thin sheet metal and plastic, it cannot carry a plow... but the rear axle being solid steel, it can pull one.

The plow is one year old, and was previously pulled by a gasoline car. It is made of construction steel: 8 mm L-profiles shaped like a letter A with double horizontal bars. The point of connection on top ensures it doesn't lift too much while plowing. It's currently fixed with an unprofessional and temporary C-clamp (there will be an U-bolt soon). It is pulled with a chain.

If snow is heavy, the L-profiles lift the plow on top of snow, and you have to plow the same road many times. Sometimes it veers off sideways. Generally, you have to catch the snow early with this system - if you're late, you're stuck. :)

Not many advantages, but dirt cheap. Don't go plowing public roads with such devices - it is nearly invisible to fellow drivers, and cops would get a seizure.

 

Some Chinese researchers have found a new catalyst for electrochemically reducing CO2. Multiple such catalysts are known, but so far, only copper favours reaction products with a carbon chain of at least 2 carbons (e.g. ethanol).

The new catalyst requires a specific arrangement of tin atoms on tin disulphate substrate, seems to work in a solution of potassium hydrogen carbonate (read: low temperature) and is 80% specific to producing ethanol - a very practical chemical feedstock and fuel.

The new catalyst seems stable enough (97% activity after 100 hours). Reaction rates that I can interpret into "good" or "bad" aren't found - it could be slow to work. The original is paywalled, a more detailed article can be found at:

Carbon-Carbon Coupling on a Metal Non-metal Catalytic Pair

Overall, it's nice to see some research into breaking down CO2 for energy storage, but there is nothing practical (industrial) on that front yet, only lab work.

 

To make no excessive claims, I have to admit I burnt a fair bit of wood during the night. In the morning however, around 9 o'clock, the solar fence (nominal power 2400 W) was giving 600 W and steaming vigorously. By 10 o'clock, it had thawed and gave 940 W. Later, other panel arrays took over and wattage decreased. The energy was used to run a heat pump.

P.S. Knowing that server resources aren't infinite, I hosted the image externally, I hope that hosting on "postimages.org" works smoothly.

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submitted 2 years ago* (last edited 2 years ago) by perestroika@slrpnk.net to c/abolition@slrpnk.net
 

The short war which Azerbaijan waged against Armenian-populated Karabakh after a months-long blocade is over (Armenian separatists lost, and will likely get ethnically cleansed out of the region)...

...but in the aftermath, it's worth pointing out that several high-profile Azeris did speak against their government starting a war - and were repressed.

The most worrisome case is the chairman of the confederation of trade unions, Afiaddin Mammadov. A provocateur who had previously injured himself threw a knife at him, and cops arrested him immediately after that, claiming he had injured the provocateur.

 

To my knowledge, this is the second time a sample is returned from an asteroid to Earth - only preceded by Hayabusa-2 fetching a sample from asteroid Ryugu. The capsule has been found and the sample stabilized with nitrogen. Fetching the sample required 7 years, studying it will require a bit of time too.

It is too early to speculate whether interesting discoveries will follow, but Bennu is considered to be an interesting asteroid - likely not a break-up product, but something that represents the original composition of the solar system.

Bennu is also considered a hazardous space object, ranked high on the Palermo scale of impact risk and kinetic yield, so knowing what it's made of can be practically worthwhile.

More information here:

https://en.wikipedia.org/wiki/OSIRIS-REx

 

The inverse vaccine, described in Nature Biomedical Engineering, takes advantage of how the liver naturally marks molecules from broken-down cells with “do not attack” flags to prevent autoimmune reactions to cells that die by natural processes.

PME researchers coupled an antigen — a molecule being attacked by the immune system— with a molecule resembling a fragment of an aged cell that the liver would recognize as friend, rather than foe. The team showed how the vaccine could successfully stop the autoimmune reaction associated with a multiple-sclerosis-like disease.

 

Most people would typically think than smelling a scent (unless it's a powerful poison or medicament) won't change much in a person's health... but apparently, a variation in the scent environment has effect on the human brain, especially if the person is already old and their senses are degrading. It has also been observed that viral infections damaging a person's olfactory nerves result in changes to the brain - with less input, the neural networks involved with scent tend to atrophy. Coinidentally, some neural networks involved with scent recognition are also involved with memory.

Prios studies already support the idea that training one's sense of smell helps older people avoid cognitive deterioration. This study brings highly significant statistical results and adds one bit - wakefulness is not required to benefit. Apparently, the stimulation a person receives from feeling different scents bypasses sleep (or maybe, even improves the quality of sleep).

 

Long story made short: apparently, the previous administration didn't really try (since it was Bolsonaro's, I am not surprised). EU import controls and financial interventions have also helped:

He believes the slowdown is due to a combination of factors: the resumption of embargoes and other protection activities by the government, improved technical analysis that reveal where problems are occurring more quickly and in more detail, greater involvement by banks to deny credit to landowners involved in clearing trees, and also wariness among farmers generated by the European Union’s new laws on deforestation-free trade. It may be no coincidence that deforestation has not fallen as impressively in the cerrado savanna, which is not yet covered by the EU’s controls.

 

Superconductivity is a condition of matter where resistance to electrical current disappears.

The first superconductors needed cooling to near the absolute zero. The next generation worked at temperatures of liquid nitrogen. A room-temperature atmospheric-pressure superconductor is a highly sought after material (e.g. it would expand possibilities to hande plasma for fusion research and make MRI machines easier to build).

A substance named LK-99 has recently caused interest in the research community. Its a copper-enriched lead apatite, typically made by reacting lead sulphate with copper phosphide. It is speculated to be superconductive at room temperature.

It is also thought that interesting properties are not inherent to the substance, but a particular kind of crystal lattice which this subtance obtains - if produced in certain ways.

The name LK-99 refers to Sukbae Lee and Ji-Hoon Kim, and the number refers to 1999, when these Korean researchers first stumbled upon it.

Studies back then were interrupted. They weren't certain of its properties and it was hard to make repeatably. When a researcher named Tong-Shik Choi died in 2017, he requested in his will that research into LK-99 be continued. The resources were found and his request was granted.

Then, other factors intervened, among them COVID. The first article was rejected by Nature because an extraordinary claim requires extraordinary proof. An article in Arxiv (not peer reviewed) at the end of July 2023 drew international attention, however.

Many persons and teams started attempting to replicate the experimental results. The process is still half way through, but considerable progress has been made.

  • Beijing University, school of material science + Beihang university: the experiment was made, but the effect could not be reproduced (they obtained a paramagnetic semiconductor of little interest)

  • Huazhong University, center for crystalline materials and micro/nanodevices: they obtained a diamagnetic crystal with interesting properties (repelled by a ferromagnet regardless of orientation, a property which a superconductor must have, but which is also shared by non-superconductive diamagnets)

  • National Physics Laboratory of India: failed to replicate the effect

  • Professor Sun Yue, South-Eastern University of China: got a weak diamagnetic crystal

  • Iris Alexandra (from Russia, plant physiologist): with an alternative production method, obtained a tiny but strongly diamagnetic crystal

  • Sinéad Griffin (Lawrence Berkley National Laboratory, from the US): published an article, attempting to theoretically explain how superconductivity might arise in the substance, explanatory tweet here

  • Junwen Lai (Shenyang National Material Science Laboratory, China): published an article about the electron structure of the substance, without opinion regarding superconductivity, with the opinion that gold doping would be better than copper doping

So, strong evidence is absent until now - we may have much merriness about nothing. There is a bunch of hypothesis and enough material to fit on a fingertip. :)

Background:

https://en.wikipedia.org/wiki/LK-99

 

I noticed that we have a community for talking about applied science and engineering in the form of c/technology, about climate science in the form of c/climate, but there didn't seem to be a field-neutral place to discuss any sort of science.

To fill the absence and introduce a few articles which caught my interest, I created it. I think I should make this thread stick to the top of the community, so meta-discussion could be easily located here.

 

People at MIT made a capacitor of cement and carbon black (not to be confused with soot). It worked and they are planning to test bigger samples. The construction of such capacitors is easy and they can be structural elements in architecture.

 

To summarize: people have known that cows' methane production can be reduced with an appropriate diet for quite some years. There has been a fair bit of searching for what that diet could be - tropical algae from high seas may produce the right outcome but aren't readily available where the cows graze.

It is nice to learn that daffodils also do the trick, and reduce methane production by "at least 30%" (a cautious estimate, some results using artificial cow stomachs have given a reduction of 96%).

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