Yes, this is a really fun idea and something that we want to do. Though these days we’re setting our sights higher than Nintendo…
A funny story though: a regular conference gimmick we have is “Man vs. Machine” where we have attendees race our fuzzer to the end of Mario level 1-1. We did this at the final year of Strange Loop, and the fuzzer was winning handily until not one, not two, but three different professional speedrunners walked by and destroyed us.
There have definitely been some applications of this sort of thing to speedrunning -- though far less sophisticated than the approach here, and usually only testing against a very small subset of the game. I've heard of some of this kind of work being done before on e.g. SM64.
I've also done something along these lines myself in Super Metroid. Mother Brain's neck moves in a conceptually simple but very chaotic pattern influenced by Samus's vertical movement, and there's a cutscene during the fight where the positioning of her neck can make a difference of about 7 seconds. The TAS fight used complicated movement to manipulate her neck position developed through much trial-and-error, while the best known human-viable manips were several seconds slower.
I wrote a program to search the state space for optimal movement patterns, and working with some speedrunners we were able to come up with a new human-viable manipulation that matched the previous TAS fight, as well as a new TAS manipulation that saved an additional 41 frames.
Do you have a citation for this? The most Gemini could say is: "While research has not identified a specific tsunami stone located at the Fukushima Daiichi site that was directly violated, the spirit of these ancient warnings was undeniably ignored." (https://aistudio.google.com/app/prompts?state=%7B%22ids%22:%...)
I don't know if there are "Tsunami stones" in the area but the nuclear power plant is built at sea level [1] so would most probably be below them.
The issue is the height of the seawalls that was not sufficient (and perhaps historical warnings, if any, were ignored):
"The subsequent destructive tsunami with waves of up to 14 metres (46 ft) that over-topped the station, which had seawalls" [1]
Edit: Regarding historical warnings:
"The 2011 Tōhoku earthquake occurred in exactly the same area as the 869 earthquake, fulfilling the earlier prediction and causing major flooding in the Sendai area." [2]
IIRC the issue was the emergency diesel generators being flooded, preventing them from powering the emergency cooling pumps, resulting in the meltdowns from residual heat in the reactor cores and spent fuel pools.
Various construction changes could have prevented this from happening:
- the whole power plan being built higher up or further inland
-> this would likely be quite a bit more expensive due to land availability & cooling water management when not on sea level & next to the sea
- the emergency generators being built higher up or protected from a tsunami by other means (watertight bunker ?)
-> of course this requires the plan cooling systems & the necessary wiring itself working after surviving a massive earthquake & being flooded
An inland power plant - while quite wasteful in an island country - would be protected from tsunamis & certainly doable. On the other hand, I do wonder how would high concrete cooling towers handle strong earthquakes ? A lot of small cooling towers might have ti be used, like in Palo Verde nuclear generating station in Arizona.
Otherwise a bizzare case could still happen, with a meltdown possibly happening due to your cooling towers falling over & their cooling capacity being lost.
Another option is designing fail safe reactors. CANDU reactors designs are over 60 years old now and were built fail safe so that if outside power to the core is cut off the system would safe itself by dropping control rods which are held up by electromagnets into the core.
A reactor scram isn't necessarily enough -- you still have decay heat to worry about. In the case of Fukushima, the fission chain reaction was stopped but without cooling pumps the decay heat was still too much.
It seems like you should build a water reservoir at a higher elevation than the core and then apply a similar principle where valves regulate the water stream, but if the valves lose power they fail open. The reservoir can be built so that there is always enough water to cool the core.
For light water reactors this basically just amounts to a large pool up a nearby hill or in a water tower.
That is easier said than done - modern reactors are in the 1000 MW+ electrical power range, which means about 3x as much heat needs to be generated to get this much electricity - say 3000 MW.
Even when you correctly shut down the chain reaction in the reactor (which correctly happened in the affected Fukushima powerplant) a significant amount of heat will still be generated in the reactor core for days or even weeks - even if it was just 1% of the 3 GW thermal load, that is still 30 MW. It will be the most intense immediately after shutdown and will then trail off slowly.
The mechanism for this is inherent to the fission reactors - you split heavier elements into lighter ones, releasing energy. But some of the new lighter elements are unstable and eventually split to something else, before finally splitting into a stable element. These decay chains can take quite some time to reach stable state for a lot of the core & will still release radiation (and a lot of heat) for the time being.
(There are IIRC also some processes where neutrons get captured by elements in the core & those get transmutated to other, possibly unstable elements, that then decay. That could also result add up the the decay heat in the core.)
And if you are not able to remove the heat quickly enough - the fuel elements do not care, they will just continue to heat up until they melt. :P
I am a bit skeptical you could have a big enough reservoir on hand to handle this in a passive manner. What on the other hand I could image could work (and what some more modern designs include IIRC) is a passive system with natural circulation. Eq. you basically have a special dry cooling tower through which you pass water from the core, it heats up air which caries the heat up, sucking in more air (chimney effect). The colder water is more dense, so it sinks down, sucking in more warm water. Old hot water heating worked like this in houses, without pumps.
If you build it just right, it should be able to handle the decay heat load without any moving parts or electricity until the core is safe.
Yea, it seems like you could design a cooling loop that runs just off the latent heat. Im sure somebody in reactor design has sketched it out.
Some napkin math based upon heat capacity of water and assuming a 20 degree celsius input and 80 degree celsius output and 30MW heat results in about 120 liters per second of water flow needed. That is about 10 million liters of water per day, or about 4 olympic sized swimming pools. I don’t know how long you need to keep cooling for, but 10 million liters of water per day seems not insane and within the realm of possibility.
If you allow the water to turn into superheated steam you can extract much larger amounts of heat off the reactor as well.
there are reactor designs that work that way, but most civilian power plants are pressurized water reactors. it is important that the water stays pressurized or you get a chernobyl
Fukushima was based on a Westinghouse BWR (Boiling Water Reactor) design, so pressurization was not that much of an issue - if enough of sufficiently cold water was provided, there would be no meltdown.
Absolutely no causal link was shown. Maybe the nerve pains for which doctors prescribe gabapentin increase the risk of dementia on their own, or maybe there is some third factor that causes both nerve pain and dementia.
Valid comment. In general retrospective studies aren't that rigorous, yet researchers love them (usually a quick and easy publication). They aren't easy to do well because controlling for confounding factors isn't easy - even if you think you know what you need to control for, data often isn't available, and even then, how you control for it can drastically change your findings.
Then layer on top the available data. I assume in this study they just tried to create a control group and an intervention group based on gabapentin prescriptions, then tried to see how many had a dementia diagnosis. So many ways the data can mislead! Differences between the control and intervention group when it comes to total exposure to drug, other medical interventions, diagnosis rates, family history, etc, etc. They are basically going in blind.
Retrospective studies can be useful in identifying potential signals. It's what we do for drug safety regularly. But it's not rigorous enough data to start making changes to medical care - you need a more rigorous study to confirm.
But what annoys me is the coverage these studies get. The average reader thinks "oh my god!", when they should think "interesting, but there is a good chance they are seeing a signal that isn't there".
A great example of the impact is the use of hormone replacement in menopausal women. It used to be very common until a study came out showing higher rates of uterine cancer (I believe). Use of hormone replace went way down, plenty of women suffered from menopausal symptoms for a few decades.
Then a massive (160 women) prospective, randomized, controlled study (WHI) were done and it was clear the safety signal wasn't there.
Not sure why this comment is getting downvoted. The article itself states that:
> "This is an observational study, and as such, no firm conclusions can be drawn about cause and effect. The researchers also acknowledge that their study was retrospective, and they weren't able to account for dose or length of gabapentin use."
Not to be too meta, but it’s kind of boring to point out the obvious limitation of the research method.
“No casual link is proven” could be said about so much science, specifically medical science and other disciplines which limit research methods for ethical or practical constraints. So you end up with this comment in every front page post about an observational medical study. We could be discussing the actual research or its implications, instead of repeating a discussion on limitations of research methodology.
In addition, I find these types of critics to be a little too cynical even for my taste. There’s a whole group of people that feel smart by finding ways to dismiss scientific studies even when there is some actually interesting data being brought up.
On first brief reading I misunderstood the title to be causal, even though it only claims a link. I think it is worth pointing out for those who check the comments before reading.
Yes, these comments are necessary pushback against the habit of these disciplines to push interventions that don't work because their evidentiary standards are bad.
I have been writing the same thing by (ab)using the existing unit of measurement known as a bel (B), which is most commonly seen with the SI prefix “deci” (d) as dB or decibel. I write the speed of light as 8.5 Bm/s (“8.5 bel meters per second”), which resembles the expression 20 dBV (“20 decibel volts”) shown at https://en.wikipedia.org/wiki/Decibel.
Translation via Gemini (2.0 Experimental Advanced)
Kidnapping of One of the Co-founders of the Startup Ledger: Major Investigation in the Cher Region
As part of the investigation into the disappearance of a businessman, numerous gendarmes and police officers were deployed in the Vierzon area on Wednesday, January 22nd. According to our information, they are investigating the kidnapping of one of the co-founders of the startup Ledger, David Balland.
By Antoine Bailleron and Geoffroy Jeay
Published on January 22, 2025 at 11:00 PM
David Balland created, in Vierzon, in 2014, with four other partners, Ledger, a startup specializing in ultra-secure cryptocurrency wallets, notably for Bitcoin.
The significant deployment of gendarmes in a street in Méreau on Tuesday, which surprised the local population, moved to the Vierzon area on Wednesday. Numerous gendarmes and police officers were visible on the roads leading to Vierzon, and even in the sub-prefecture of Cher. A gendarmerie helicopter was seen at low altitude. In the afternoon, gendarmes even intervened on the Quai de l'Yèvre in Vierzon, breaking a window and the door of an apartment.
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Gendarmes intervened on the Quai de l'Yèvre in Vierzon, breaking a window and the door of an apartment.
According to our information, they are investigating the disappearance of a businessman, one of the co-founders of the startup Ledger, David Balland. The man was reportedly kidnapped. With a view to a ransom demand? Nothing has been revealed.
For any possible definition of "short", there's only finitely many (and typically few) theorems that have a short proof, while there are infinitely many theorems (not all of them interesting).
More in detail: Proofs are nothing more than strings, and checking the validity of a proof can be done mechanically (and efficiently), so we can just enumerate all valid proofs up to length N and pick out its conclusion.
