Came here to mention this. It's not too applicable to modern/useful cryptography, but introduces a bunch of related hidden-information concepts like product date codes, which I think I actually use far more often.
I use on Linux the utilities "par2create" and "par2verify".
On Gentoo Linux, the name of the software package that provides them is "app-arch/par2cmdline".
"par2create" needs 2 parameters, the amount of redundancy to be added and the name of the input file (which should be a compressed then encrypted archive file).
It produces several additional files, with recovery information. My script creates then a directory, moves there all the files, including the original archive file, and then aggregates the directory with all its files into a single ".pax" archive file. The ".pax" file can then be stored on a couple of HDDs or of tape cartridges.
Before creating the initial archive file, I scan the directories to be archived and I gather all the metadata of the files (names, sizes, timestamps, content hashes), which I store in a database. The metadata can later be used to search for files, to find out from which archival device they should be restored, and also to detect duplicates (by using the content hashes) that may be omitted from later backups.
When retrieving such a file with redundancy, after extracting its component files the "par2verify" utility verifies the integrity and reconstructs corrupted data, if necessary.
For working with tape drives, I prefer to use a FreeBSD server, because the FreeBSD utilities for tape drives and in general for SAS/SCSI peripherals are more convenient and more complete than those of Linux (it is also possible to use a FreeBSD VM on a Linux computer, with PCIe pass-through for the SAS HBA card used to attach the tape drive).
It is inefficient to store small files on tapes, so I usually collect data to be archived on tapes until I reach an amount of about 50 GB, then I compress, encrypt, add redundancy, aggregate again into a single file and then save it into the tape cartridges.
But Jean (English name, like Jeannie) and Jean (French form of John) are entirely different names, with different pronunciations, that happen to share the same spelling.
I am curious how you define "entirely different", because where I am looking, all the names you mention have parallel etymologies, the same origins, and similar meanings. We find them with different pronounciations and many spellings, because of the regional languages spoken, but they were adopted into a multitude of languages from the same sources. So how do you consider them "entirely different"?
When you monitor a power line, you don't get a tcpdump showing who's producing and who's consuming the power. You can't just jump straight to the culprit.
It's just bulk flows, so when a weird flow shows up, you've got to move up or down the line, past a few producers or consumers, and see if the flow changes. For a subtle effect, that might not even be so clear.
Worse, for an effect that's most visible at the medium-voltage transmission level, simply placing a monitor might take weeks. These are planned installations with incredible safety considerations -- you don't just plug in.
Finally they found a research campus with a bunch of battery storage systems, AND the ability to install a bunch of monitors, and persuaded them to install dozens of monitoring points. Finally a high-resolution view of the effect allowed them to confirm the behavior.
He mentions that he's running it in an air-conditioned studio, so presumably if the unit's datasheet lists an environmental range warmer than that, it has plenty of cooling headroom in this environment.
The last rubidium oscillator I played with, had to heat the vapor cell within the physics package, but then prevent that from overheating the rest of the unit, so it specified mounting to a heatsink. There was no heatsink recommendation given, just a certain package temperature as reported by sensor value X in the diagnostic data page. Get below that and you're golden. Get too much below that and you're wasting extra energy in the heater. Which is harmless, it just drives power consumption up.
So depending on how the unit's thermals work out, a slightly less aggressive fan may end up being mildly beneficial.
I converted from residential-class to business-class cable a few years ago. In both cases, I had routable IPv4 addresses.
I was just looking at flipping back, but now it seems the default for new resi accounts is CGNAT. They say they'll give me a real IP upon request at no additional charge, but it's anyone's guess how long that holds out.
One reason they report in MW instead of MWh, is that grid operators primarily spec systems by their continuous MW, and only secondarily mention their cumulative MWh. So that's the way they talk about them, and reporters just mimic that. Both are important, but the top-line number is MW, for sure.
One reason for this is that for a lot of grid-support functions, instantaneous or short-term power is vastly more important than long-term energy capacity. The other reason is that traditional generation is only sized by MW; you just keep pouring fuel into it forever, so the notion of MWh doesn't even enter the picture. They're not even thinking in those terms.
You and I, as battery natives, think about it the other way around. But we're not grid operators.
Yup! Some breaker trips, and a 500MW plant goes offline. How much battery storage do you need to compensate? 500MW. The fact that it stores 500MWh and therefore only lasts an hour comes afterwards, that is plenty of time to ask all the other fossil power plants to scale up a bit.
It's probably also a view that is shifting as batteries move from primarily providing short-term grid stability (where power available is probably the more important metric) to longer term storage.
I've always wondered why they don't stack them in deployment -- the containers are obviously fine with it! -- but I guess land is cheap enough not to bother.
Horizontally they need plenty of room for airflow, as each container has some HVAC-or-whatever module on the side. But vertically...
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