aoki

When shape names are first introduced, many kids will flip out if you suggest a given polygon can be multiple things at once. So they define the shapes (square, rectangle, rhombus, parallelogram, trapezoid, etc.) so they are mutually exclusive, with categories like quadrilateral as residual categories. You can tell who is doing AoPS/Beast Academy because they argue based on the standard definitions, whereas the teacher will insist on the curricular definition or on the “most specific answer.”

Another classic is “how many roots does a parabola with real coefficients have?” The answer is always two by the FTA, but the textbook Algebra 1 answer is zero, one, or two because they haven’t covered complex numbers yet.

> Back at the SFMTA, Armando told me the Breda vehicles are being replaced, and with them their destination displays will be swapped for newer LED dot-matrix units that are more efficient and easier to maintain. By the end of 2025 the signs that inspired Fran Sans will disappear from the city, taking with them a small but distinctive part of the city’s voice.

:-(

That’s viXra

Once upon a time, editors requested submissions in single-column, double-spaced form because they (or the in-house writers) would actually mark on the printed-out paper. Mysterious glyphs, squiggly arrows, and indecipherable handwritten text would be inscribed between the lines in red ink. Many journal preprints from that era are double-spaced.

Even more mysterious are the arcane notations such as “TABLE 1 ABOUT HERE” with the actual table/figure contents placed at the end of the paper. Understandable when authors provided hardcopy figures for photoreproduction, baffling when the entire submission was generated with LaTeX or Word.

The deepest compartments (below the waterline) are often like this. It is not always possible for taller equipment spaces (engineering, magazines) in small ships. Crew berthing is often below the waterline and accessed via deck hatches as you say, but you do end up with hard choices when the space is flooding and people are still unaccounted for. Hope you can stabilize the ship or run it aground before it sinks, or 100% guarantee that some crew will drown?

Above the waterline, it is common to have “loops” of passageways for movement of equipment and people (including casualties). Firemain stations will be spaced along such a loop because they are used to both fight nearby fires and dewater the compartments below.

Can’t speak for the Norwegians but that is not how at-sea watchstanding works in, e.g., the US Navy. The OOD is the captain’s delegate in operating the ship. In peacetime steaming, there may not be another khaki (officer or chief petty officer) on watch who is qualified to stand OOD - the JOOD/JOOW is typically a trainee, and the CIC watch officer is often a non-OOD-qualified junior officer or chief petty officer. They can and should all provide support to the OOD but usually nobody is available to babysit or step in. All of the babysitting should have happened before the OOD ever got their OOD qual.

Which btw tells you what has gone wrong in many of these situations: the OOD was given a qualification they were not ready for, because not having enough OODs means the actually-qualified OODs will be standing port/starboard watch and be exhausted all the time. COs and XOs give the weak OODs quiet steaming watches they think will be easy, but a shipping channel can get busy earlier than expected and everything can go to shit really quickly.

In the modern US military, it’s a truism that if anything seriously goes wrong on a ship, the captain has ultimate responsibility and will be fired. (Whereas before WW2, future admirals like Nimitz ran their ships aground and were not fired.) This leads to a zero-defects mentality on the part of the leadership of a ship, which in turn explains why junior officers fail to call the CO to the bridge (or call too late) when they get into a bad situation.

Pure math has a far greater vulnerability to this than applied math. Top journals have impact factors of around 5.0. Respectable but tiny specialist journals can have impact factors less than 1.0 (like, 0.4). Meanwhile, MDPI Mathematics is a Q1 journal with an impact factor over 2.0.

The now-standard bibliometrics were not designed by statisticians :-)

The issue in all fields became significantly worse as developing countries decided their universities needed to become world class and demanded more international publications for promotion. Look at the universities in the table in the paper and you can see which countries are clearly gaming the system. If your local bureaucrats can’t tell which journals are good and which are fake, the fake journals become the most efficient strategy. Even worse, publishers figured out that if you can attract a few high-citation papers, your impact factor will go way up (it’s an arithmetic mean) and your fake journal becomes “high quality” according to the published citation metrics!

Math is particularly susceptible to this because there are few legitimate publications and citation counts are low. If you are a medical researcher you can publish fake medical papers but more easily become “high impact” on leaderboards (scaled by subject) by adding math topics to your subjects/keywords.