Recent submissions

Comment · 1 year ago
The difference is being seen in public is ephemeral and being recorded in public is eternal. In the former, your actions exist in fallible human memories for a short while at most; in the latter there is a permanent digital record of you, geotagged and time stamped and available for perfect recall forever.
Comment · 1 year ago
And a long one at that. I’m sure I could do well as an electrician eventually, but there’s no way I could make it through 4+ years as an apprentice making $21/hr, and then another three as a journeyman (even if it pays double). Maybe when my house is paid off (but who’s going to hire a 50yr old apprentice?).

The biggest problem with an apprenticeship model is that it creates a bottleneck to getting people into the trades. You need competent journeymen (and knowing the trade isn’t enough, they need to be able to teach) who ideally can take on more than one apprentice at a time. But no matter how much everyone “wants young people in the trades” and no matter how much of a “shortage of tradespeople” there is, the bigger shortage is apprentice positions. Every kid in the world could suddenly decide they want to be electricians and plumbers, and it would still take two generations to fill the ranks.

Note that I’m mostly focusing on trades that require state licensing. Laborers, carpenters, painters, plasterers, welders, etc. don’t suffer this problem as much, because there is no set amount of time for someone to be an apprentice. If you’re good and reliable you’re getting promoted fast. I’m not against licensing per se, but I am strongly against legislated work requirements for a job.

I know I could study for a week and pass the master electrician exam on Monday.

Comment · 1 year ago
Safari mobile reader mode works fine. It even recognizes the “next page” links and renders all four at once.
Comment · 1 year ago
Comment · 1 year ago
Does anyone what the "international symbol dictionary" Susan Kare used was?
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Comment · 2 years ago
Would also like to see a ban on firmware updates and programming tools locked behind a dealer (or support contract) portal and a ban on time-restricted software licenses for hardware.

In line with remote-bricking discontinued hardware, these policies only serve to generate eWaste.

If you sell programmable hardware, or really anything with embedded software, you should be required to make all the tools and software available to end users (doesn’t have to be free, but shouldn’t require a subscription or support contract either) in perpetuity.

Licenses to enable additional hardware features are fine, but they must be granted for the life of the device (i.e. as long as it can be kept working), not an arbitrary “we think the life of this thing is 5 years”. You should never have to keep paying to use a device you already bought.

Comment · 2 years ago
Comment · 2 years ago
Engine speed has nothing to do with power generation, these are totally separate systems. It's not like a diesel train with electric motors; on this ship (and most others) the engine is directly coupled to the prop.

The engine requires one of the HV generators to remain online so that oil and cooling pumps operate (and also to bring fresh air in to the engine room for the crew, but those fans can probably run off the emergency genset). Once the HV generators were disconnected, the pumps shut down and the engine stopped. Restarting the engine is a process. Here's how it's done for a small engine (5500hp)[1]. And for something similar to the Dali (55,626hp)[2].

The circuit breakers are a little different than common magnetic household breakers. They will trip in over-current scenarios of course, but also for over- or under-voltage, over- or under-frequency, or if triggered by the ship's SCADA system(s). Breakers tripping on the HV and LV side of the transformer makes me think that they tripped because of something other than over-current.

Three things in the report caught my attention:

1) The crew initially tried resetting the tripped breakers (HR1 and LR1) instead of energizing the alternate set (HR2 and LR2) which they had been operating on for months.

2) The second blackout was caused by the diesel generator breakers (DGR3 and DGR4) tripping. The report doesn't specify whether they began startup procedures for generators 1 and 2 when HR1 and LR1 tripped (probably not, because at this point gensets 1 and 2 were still operating), but it does say that genset 2 was in standby and connected automatically after the second loss of power. With #3 and #4 online, adding #2 to the mix isn't as easy as throwing a switch, it has be to be synchronized to the frequency of the other two first and this takes some time. But once DGR3 and DGR4 opened, DGR2 could be closed immediately and DGR1 wouldn't be far behind (i.e. as soon as generator #1 was synced to generator #2). I expect the state of the generators will be fleshed out more fully in later reports.

3) The report makes no mention of the state of the compressed air tanks. There should have been sufficient compressed air available to attempt several restarts (up to a dozen per regs), so running the compressors wouldn't be necessary. But if there wasn't enough stored compressed air, then no matter what the crew did with the electrical system wouldn't have mattered; they wouldn't have had time to fill the tanks enough to restart the engine. Again, I expect this to be covered in later reports.

My guess is that there was some fault with transformer #1, which caused HR1 and LR1 to trip off. When it was brought back online and they attempted to restart the engine, the combined load of normal ship operations, additional startup equipment (combustion air blowers, etc) along with whatever (possibly intermittent) fault TR1 had overloaded the generators, which then tripped offline. Perhaps instead they should have closed HR2 and LR2, and started an additional generator before attempting an engine start. But that's just a guess. The report doesn't mention any restart attempts, so there may have been other electrical faults that needed to be sorted out first.

Also, having used up some compressed air to start the engine at the dock, they may have been running the compressors to bring the tanks up to the required stored capacity which would have contributed to the load on the electrical system (but only up to the first blackout, as they wouldn't have restarted automatically).

1: https://www.youtube.com/watch?v=J-D9Ka3TM1I 2: https://www.youtube.com/watch?v=5mFmCxOjY_A

Comment · 2 years ago
> We’ve all heard how JFK outsmarted Nixon during their televised debate by wearing a blue shirt, because blue showed up as white whereas Nixon’s white shirt showed up as gray.

Huh. I always heard that Nixon refused makeup and JFK didn’t, with the result being about the same: Kennedy looked healthy and Nixon looked like a sweaty corpse. But considering the quality of TV screens and broadcasts in 1960, the shirt thing sounds more realistic.

Comment · 2 years ago
I guess that’s true if you’re west of DC. Otherwise it’s Delmarva (DELaware, MARyland, VirginiA).
Comment · 2 years ago
Many (30ish) years ago, I subscribed (or my parents did on my behalf, I was 9) to Model Railroader magazine. A significant portion of that hobby seemed to be focused on this sort of photography and the construction or use of these lenses.

I haven’t thought about it much since then (or much at the time, since I was a lot less interested in the detailed modeling and a lot more interested in the control systems and coming up with complex track layouts), but the pictures those guys took were always pretty cool.

Comment · 2 years ago

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