one difference is that a phase change stores energy at constant temperature, which may be desirable given that heat pump efficiency is inversely proportional to temperature output temperature

battery life span is defined as when the reach 80% of their original capacity. it's possible that the decline will accelerate after that point but they aren't suddenly useless

Presumably an exponential decay, as for most tool lifetimes.

i was using ipv6 at home for years but then one day at&t broke it and never fixed it

it takes surprisingly few trucks to keep stores stocked. most of the trucks you see driving around are either delivering packages or hauling bulk cargo that used to go by rail

> it likes to change the content while keeping Content-Length intact

thanks, i had repressed that memory

Please suffer.

hulu's live tv feature uses commercial detection to stop you from from fast-forwarding through commercials in recordings

The tanks to hold liquid CO2 will likely be a lot cheaper than compressed air tanks because the required pressure is much lower. But they are going to loose a lot of energy to cooling the gas and reheating the liquid. I would be surprised if the round-trip efficiency is higher than 25%.

They claim 75% efficiency AC-AC [0], and they point out that there’s no degradation with time. What estimates are you using to arrive at the 25% figure?

[0] https://energydome.com/co2-battery/

i didn't do any math tbh, i just took the 25% number from the wikipedia page for cryogenic energy storage. i assumed their efficiency would be lower of the smaller temperature differential, but maybe it will be higher because they are storing part of the energy as pressure rather than temperature

The energy used to liquefy the CO2 is the bulk of the energy stored. They don't throw it away afterwards. The the liquid-gas transition is why this works so much better than compressed air.

of course they are not throwing the energy away. but by using a working fluid that changes phase they are trading away energy efficiency for power density, for the same reason that steam engines are less efficient than stirling engines.

Heat from compression is stored in a thermal energy storage system. Most likely something like a sand container.

the article talks a lot about PSOs but never defines the term

"Pipeline State Objects" (immutable state objects which define most of the rendering state needed for a draw/dispatch call). Tbf, it's a very common term in rendering since around 2015 when the modern 3D APIs showed up.

PSOs are Pipeline State Objects, they encapsulate the entire state of the rendering pipeline.

anyone want to buy a 2x16 GB DDR4-3200 kit that only fails memtest86 some of the time?

I wonder if semi-reliable RAM could be made to work for training. After all gradient descent already works in a stochastic environment, so maybe the noise from a few flipped bits doesn't matter too much.

Also, depends on the nature of the error. If only a small memory range is affected, you could patch the kernel to avoid it.

No need for patching you can disable specific ranges on Linux using the memmap kernel parameter. It's often used for that purpose.

Sorry but I am looking for reliability. Do you have any stick that fails 100% of the time?

Have you tried underclocking or loosening the timings?

my experience is if even memtest86 fails the memory is truly borked.

Well, it kind of depends. With XMP (which is overclocking) I've found plenty of kits on Ryzen not passing memtest with the XMP settings. Different CPUs seem to be able to run their memory controller harder without error.

And then there are other factors like more sticks of ram stressing things further. I had to downclock to get memtest stable when running 4 sticks even though each kit ran fine on it's own. But that is expected as well as 4 sticks stresses the memory controller even further.

I confess I don't have any real recent experience with DDR5 though, mostly with DDR4 on Ryzen 1000-5000 series.