bill3478's comments

> to properly articulate their problems using the jargon of mathematicians and programmers

I once distilled a real-life problem into mathematical language exactly like how the Introduction to Algorithms book would pose them only to have the quesiton immediately closed with the explanation "don't post your CS homework".

(My employer at the time was very sensitive about their IP and being able to access the Internet from the work computer was already a miracle. I once sat through a whole day of InfoSec and diciplinary meetings for posting completely dummy bug repoduction code on Github.

If this were true, then treating any question as an X-Y problem shouldn't be allowed at all. I.e. answers should at least address the question as posed before/instead of proposing an alternative approach.

In reality the opposite is encouraged. For countless times, I've landed on questions with promising titles/search extracts, only to find irrelevant answers because people grabbed onto some detail in the question irrelevant to my case and provided X-Y answers.

This often also causes subsequent useful questions to be marked as dups even though they no longer contain that irrelevant detail. The appeal process is so unfriendly that most would not bother.

See also: https://news.ycombinator.com/item?id=36068243

Really not sure what/who this is for. There aren't many 3-phase LV AC + DC use cases apart from industrial load + control. I can't imaging the DC part can be transmitted at a voltage that will make the system efficient while avoiding an expensive step-down conveter.

Wouldn't that be POE+=2?

Also, if this is anything like USB it will be PoE 3.14 Gen 2 type E.

Many supermarket chains (in the West at least) have satellite links at their major locations because they can't afford to close a store just because the local ISP had an issue.

The real question is how long can some of the smaller banks' datacenters stay up.

They can use GPS to synchronise or back-to-back DC if available.

A true black start has several factors (which make it difficult and notable):

1. The grid has to fully collapse with no possibility of being rescued by interconnection

2. As a result, a generation asset has to be started without external power or a grid frequency to synch to

3. An asset capable of this is usually a small one connected to a lower voltage network that has to then backfeed the higher voltage one

4. Due to the difficulty of balancing supply/demand during the process, the frequency can fluctuate violently with a high risk of tripping the system offline again

None of this applies in yesterday's case:

The rest of the European synchronous grid is working just fine.

News reports stated Spain restored power by reconnecting to France and Morocco.

By reestablishing the HV network first, they can directly restart the largest generation asset with normal procedures.

As they bring more and more load or generation online, there's little risk of big frequency fluctuations because the wider grid can absorb that.

Of the top 10 languages on https://www.tiobe.com/tiobe-index/, only Visual Basic uses ^ as the power operator. Google must really like Visual Basic.

Is that the power operator or the xor operator?

Is not that OpenJDK developers can't prevent these, but there's a forbidding cost for doing so.

The simplest "safe" way of doing this involves defensively copying the input argument. However, the `compress` function will likely make yet another smaller copy, making the constructor very allocation and CPU intensive.

In fact, due to the fixed array size in Java, all thread-safe implementations must either allocate two arrays to hold the two possible encodings, which guarantees one piece of garbage, or iterating the input array twice.

For such a core class like String, this is probably unacceptable cost. And the constructor is not documented to be thread-safe, so no one should expect it to.

In reality, there are much more impactful data structures to abuse in Java.