7 ms·

While having algorithms and computers dictating every aspect of train movements, crew scheduling, resource allocation is efficient and in a sense optimal, I thi

While having algorithms and computers dictating every aspect of train movements, crew scheduling, resource allocation is efficient and in a sense optimal, I think there's something compelling to be said about having a system that can survive with human-rememberable patterns when such an optimizer fails. That it can fall back on (or have at the core) simple patterns that people can still operate without algorithmic intervention. I.e. the algorithmic tuning enhances at the edges, and isn't at its core some tangled non-interpretable system that someone can't operate without computer assistance. The idea of a protected set of core routes and staffing patterns that operates without having to be computer-determined? I used to be so impressed at European train stations that they had a single sheet that would give the entire day's arrivals and departures, down to which track. I assume that behind that were schedules that weren't so far from being hand-calculated with equivalent sheets that told people and equipment where to be at what times. I think we lose something when we jump so far forward that you cannot fall back gracefully without a system completely breaking down.

pjmlp 5y ago
There is an Isac Asimov book about this. A crew is stranded in space, because of a computer malfunction and no one on board remembers how they used to be programmed.
- at-fates-hands 5y ago
  Is that "The Last Question"? https://en.wikipedia.org/wiki/The_Last_Question https://en.wikipedia.org/wiki/The_Last_Question
  - Tenoke 5y ago
    Are you posting it reflexively because 9 out of 10 times Asimov is mentioned that's the story people talk about? Because that's definitely not the plot of it.
    - andybak 5y ago
      7/10 times. The other three are the Carthage time-viewing story.
- KineticLensman 5y ago
  In at least one Arthur C. Clarke short story the problem doesn’t arise because they still have sliderules
- 0xdeadb00f 5y ago
  I was going to say it kinda reminds me of the AI(s) in Neuromancer. In that novel it felt like the AIs were 1000 steps ahead of humans and pretty much just using then as pawns, selecting them carefully from the population, knowing they could either abuse their conditions to control them, or just flat out blackmail them.
vages 5y ago
I work within the train system of a European country (with ticketing, so I’m on the top and not the bottom of things). From my experience with station and onboard crew, I am very certain that the schedules and patterns are still very much human rememberable, at least collectively: People have to show up for work, drive the train and many other things. My guess is that the failure is related to signalling or some other knowledge that exists “between” the trains (and brains). Having systems that can negotiate right of way is necessary to increase the number of trains and the speed of each individual train beyond their pre-computer-era limits. Having all trains stop for one day is probably a judgment call to lower the overall duration: Having all trains stop for a day is a pain in the neck, but you know when you’re done. If you could not wait, you could probably have (quite) a few trains run without problems. However, you would have to work for a very long time to get all the trains back to where they were to resume the regular time table. This would be the preferable option during a time of crisis.
- Aperocky 5y ago
  Commercial Flights can still be flown manually, without many automated sensing system. But if they don't work you don't take off, it's simply not worth the risk.
- Foobar8568 5y ago
  Try to run the pricing system in Denmark if it hasn't been changed over the years.... It was "deem" "impossible" for a human to calculate the pricing within a reasonable amount of time (with all the associated bonus). Do not forget that there might several companies running on the same track, cargoa and passenger trains etc. Managing a busy track is hell.
  - vanderZwan 5y ago
    > It was "deem" "impossible" for a human to calculate I live in Malmö so you have to understand I'm obliged to make a "well no wonder given the Danish counting system" joke here > Fifty is halvtreds, which stands for halvtredje-sinds-tyve, meaning “third half times twenty”, or “two scores plus half of the third score” [2½ 20]* https://www.languagesandnumbers.com/how-to-count-in-danish/en/dan/ https://www.languagesandnumbers.com/how-to-count-in-danish/e...
pmontra 5y ago
The train schedule as seen by passengers stays the same for years, often to the rail number in stations. What changes are the crews, wagons, locomotives, possibly routes on the railway (switches and reactions to delays and failures.) A friend of mine worked at an app used by a railway's personnel to know where to go next. The app was not particularly complicated but the backend, which has been running for ages, took a long time to run. I don't know the details.
lbriner 5y ago
You also have to ask at what cost to maintain the backup system and how easy it is to test the Disaster Recovery process. If once in a while, you have a few hours delay (or in this extreme case, a whole day) you might ask if it would be worth it, especially if you could only test it by adding random failures to the main system like Netflix do! As another poster mentioned, they are many, many independent variables in a railway system. In the old days, people recovered from problems by gut feel and experience was OK although there is usually no "right" answer. The newer systems apply some statistical anlysis and try and make the best decision usually with humans doing the last part. I'm not sure about "because safety" though since signalling systems protect trains from each other and they only have automation in the sense of first train that arrives gets it route sets, the system cannot make trains crash unless there is a critical bug.
djcapelis 5y ago
As a general response not specific to this system failure: Train systems are designed to fail safe when not in state and significant safety engineering is done to ensure that if a rail system remains in a known good state over multiple decades almost every potential threat to human life caused by various equipment failure possibilities is quantified and reduced to a level of risk that’s acceptable. (Zero typically, for any known non-adversarial risks.) Many of the pathways in the fault tree involve shutting something down if it’s out of the correct state. So you will see train networks fail safe rather than run in a regressed state since these vehicles with up to a thousand human lives on board drive themselves to some degree in every modern system and we tend to hold them with a level for safety incompatible with easily winging it when something is wrong. This absolutely makes the system more brittle and less resilient, but for the most part it’s the tradeoff we accept in most modern rail engineering projects which are designed with the goal of reducing human loss of live to zero over the entire span of the system’s operational lifetime. That said, train systems themselves usually maintain a ton of active operational procedures that remain part of staff training which would theoretically allow them to be more resilient and these procedures are kept current and you will often see them used in emergencies. I.E. on automated systems, trackway signaling often exists in the “not lit” off state and if the automated train control system failures, is often capable of lighting up for human controlled movement (usually required to be done at reduced speeds) of the trains during irregular operations like bringing stuck trains to the end of their lines and letting the people in them out at the next station. And any trains that still have a human conductor in a cab (or a cab for a human conductor at all) have procedures for that human to operate the train directly, even on segments of track where automated train control otherwise control all train movements. We could try and run these systems in these degraded states under these emergency procedures, but most modern systems have safety analysis and engineering which focus on bringing the system to a safe halt state while fixing the underlying issue and returning to full operational state rather than messing around with rolling along in degraded states with unknown but assumed to be increased potential for catastrophic engineering failures with outcomes including loss of life. (In the US it is generally illegal for a human being to operate a train unaided by some form of train control above 79mph. Most other systems have similar rules. We no longer trust humans themselves to operate these vehicles just because so many human lives can be at stake when they fail.) Source: I did a stint working on system security and a little bit of electromagnetic compatibility safety engineering for rail systems. It was enlightening to see how the capital E engineers I was working alongside handle these concepts and design risk out of modern systems. The bulk of my work was in the US but the parts that weren’t were on systems that spanned multiple continents and/or train cars which were distributed worldwide. (To my knowledge none of my work has ever related to system discussed here.)
laurent92 5y ago
> I assume that behind that were schedules that weren't so far from being hand-calculated It’s more than that: The trains are negotiated at political levels! The “8:18 to Marseilles” (fictitious example) could be a headline in the news if the region refuses to fund it, and the worker’s union may have striked to keep it, while inhabitants’ HOA has negociated with the city to keep it under 12€: They are the object of a convergence of fixed interests. They run for generations: the train I took as a kid is still arriving on the same track today (and in one stop, it stops at track E; tracks A-D were dismantled but never renumbered due to this legacy). The good thing with rails is that they aren’t going away, and trains can be negotiated for decades, they’re far from being scheduled on-the-fly.

pjmlp 5y ago

There is an Isac Asimov book about this. A crew is stranded in space, because of a computer malfunction and no one on board remembers how they used to be programmed.

at-fates-hands 5y ago
Is that "The Last Question"? https://en.wikipedia.org/wiki/The_Last_Question https://en.wikipedia.org/wiki/The_Last_Question
- Tenoke 5y ago
  Are you posting it reflexively because 9 out of 10 times Asimov is mentioned that's the story people talk about? Because that's definitely not the plot of it.
  - andybak 5y ago
    7/10 times. The other three are the Carthage time-viewing story.
KineticLensman 5y ago
In at least one Arthur C. Clarke short story the problem doesn’t arise because they still have sliderules
0xdeadb00f 5y ago
I was going to say it kinda reminds me of the AI(s) in Neuromancer. In that novel it felt like the AIs were 1000 steps ahead of humans and pretty much just using then as pawns, selecting them carefully from the population, knowing they could either abuse their conditions to control them, or just flat out blackmail them.

vages 5y ago

I work within the train system of a European country (with ticketing, so I’m on the top and not the bottom of things). From my experience with station and onboard crew, I am very certain that the schedules and patterns are still very much human rememberable, at least collectively: People have to show up for work, drive the train and many other things. My guess is that the failure is related to signalling or some other knowledge that exists “between” the trains (and brains). Having systems that can negotiate right of way is necessary to increase the number of trains and the speed of each individual train beyond their pre-computer-era limits. Having all trains stop for one day is probably a judgment call to lower the overall duration: Having all trains stop for a day is a pain in the neck, but you know when you’re done. If you could not wait, you could probably have (quite) a few trains run without problems. However, you would have to work for a very long time to get all the trains back to where they were to resume the regular time table. This would be the preferable option during a time of crisis.

Aperocky 5y ago
Commercial Flights can still be flown manually, without many automated sensing system. But if they don't work you don't take off, it's simply not worth the risk.
Foobar8568 5y ago
Try to run the pricing system in Denmark if it hasn't been changed over the years.... It was "deem" "impossible" for a human to calculate the pricing within a reasonable amount of time (with all the associated bonus). Do not forget that there might several companies running on the same track, cargoa and passenger trains etc. Managing a busy track is hell.
- vanderZwan 5y ago
  > It was "deem" "impossible" for a human to calculate I live in Malmö so you have to understand I'm obliged to make a "well no wonder given the Danish counting system" joke here > Fifty is halvtreds, which stands for halvtredje-sinds-tyve, meaning “third half times twenty”, or “two scores plus half of the third score” [2½ 20]* https://www.languagesandnumbers.com/how-to-count-in-danish/en/dan/ https://www.languagesandnumbers.com/how-to-count-in-danish/e...

pmontra 5y ago

The train schedule as seen by passengers stays the same for years, often to the rail number in stations. What changes are the crews, wagons, locomotives, possibly routes on the railway (switches and reactions to delays and failures.) A friend of mine worked at an app used by a railway's personnel to know where to go next. The app was not particularly complicated but the backend, which has been running for ages, took a long time to run. I don't know the details.

lbriner 5y ago

You also have to ask at what cost to maintain the backup system and how easy it is to test the Disaster Recovery process. If once in a while, you have a few hours delay (or in this extreme case, a whole day) you might ask if it would be worth it, especially if you could only test it by adding random failures to the main system like Netflix do! As another poster mentioned, they are many, many independent variables in a railway system. In the old days, people recovered from problems by gut feel and experience was OK although there is usually no "right" answer. The newer systems apply some statistical anlysis and try and make the best decision usually with humans doing the last part. I'm not sure about "because safety" though since signalling systems protect trains from each other and they only have automation in the sense of first train that arrives gets it route sets, the system cannot make trains crash unless there is a critical bug.

djcapelis 5y ago

As a general response not specific to this system failure: Train systems are designed to fail safe when not in state and significant safety engineering is done to ensure that if a rail system remains in a known good state over multiple decades almost every potential threat to human life caused by various equipment failure possibilities is quantified and reduced to a level of risk that’s acceptable. (Zero typically, for any known non-adversarial risks.) Many of the pathways in the fault tree involve shutting something down if it’s out of the correct state. So you will see train networks fail safe rather than run in a regressed state since these vehicles with up to a thousand human lives on board drive themselves to some degree in every modern system and we tend to hold them with a level for safety incompatible with easily winging it when something is wrong. This absolutely makes the system more brittle and less resilient, but for the most part it’s the tradeoff we accept in most modern rail engineering projects which are designed with the goal of reducing human loss of live to zero over the entire span of the system’s operational lifetime. That said, train systems themselves usually maintain a ton of active operational procedures that remain part of staff training which would theoretically allow them to be more resilient and these procedures are kept current and you will often see them used in emergencies. I.E. on automated systems, trackway signaling often exists in the “not lit” off state and if the automated train control system failures, is often capable of lighting up for human controlled movement (usually required to be done at reduced speeds) of the trains during irregular operations like bringing stuck trains to the end of their lines and letting the people in them out at the next station. And any trains that still have a human conductor in a cab (or a cab for a human conductor at all) have procedures for that human to operate the train directly, even on segments of track where automated train control otherwise control all train movements. We could try and run these systems in these degraded states under these emergency procedures, but most modern systems have safety analysis and engineering which focus on bringing the system to a safe halt state while fixing the underlying issue and returning to full operational state rather than messing around with rolling along in degraded states with unknown but assumed to be increased potential for catastrophic engineering failures with outcomes including loss of life. (In the US it is generally illegal for a human being to operate a train unaided by some form of train control above 79mph. Most other systems have similar rules. We no longer trust humans themselves to operate these vehicles just because so many human lives can be at stake when they fail.) Source: I did a stint working on system security and a little bit of electromagnetic compatibility safety engineering for rail systems. It was enlightening to see how the capital E engineers I was working alongside handle these concepts and design risk out of modern systems. The bulk of my work was in the US but the parts that weren’t were on systems that spanned multiple continents and/or train cars which were distributed worldwide. (To my knowledge none of my work has ever related to system discussed here.)

laurent92 5y ago

> I assume that behind that were schedules that weren't so far from being hand-calculated It’s more than that: The trains are negotiated at political levels! The “8:18 to Marseilles” (fictitious example) could be a headline in the news if the region refuses to fund it, and the worker’s union may have striked to keep it, while inhabitants’ HOA has negociated with the city to keep it under 12€: They are the object of a convergence of fixed interests. They run for generations: the train I took as a kid is still arriving on the same track today (and in one stop, it stops at track E; tracks A-D were dismantled but never renumbered due to this legacy). The good thing with rails is that they aren’t going away, and trains can be negotiated for decades, they’re far from being scheduled on-the-fly.