Ahoi! Participated to the development of a simulation tool for that purpose. Many factors need to be taken into account:
- The gradients of the track
- How agressively you want to drive at different time of the day
- How many trains
- The timing of the trains.
When one train brakes, it can power another one that accelerates at the same moment
- The efficiency of the power chain
- The resistance model of the train
With so many parameters the results can be quite volatile.
However, rule of the thumb in the business is that 30% saving can be achieved with good energy management. Hope this clarifies a little.
What else is new? This was already well known among grad students in the late 90s. We even knew there was some kind of hierarchy, with one of the student acting as «political officer».
I will just chime in to mention Draftable (https://www.draftable.com/compare). It really works well. It’s not so easy to have a visually comfortable diff of two PDFs.
I cannot agree more with the author’s point of view. As an illustration, many people want to use GPS for the safe positioning of trains in the European Train Control Systems. This makes the space sector happy because it justifies the expenditures incurred for putting things like Galileo in orbit. However, in a pre-war check exercise, one immediately come to the conclusion that all European trains would crawl to a stop in case the GPS is jammed or interfered with. We were not very listened to… until Ukraine.
Critical infrastructures should not depend from things that are located in space or on the other side of the planet. These are one of those things were market logic should be anticipated with regulations (we can’t wait for the next Titanic). Another point touched by the article.
This correct. Power lines wear induced by pantographs is the limiting factor for TGV top speed.
The engineer that can solve this problem will allow top speeds in the range of 400/500 kph on /existing/ TGV tracks. Much better problem to solve than hacking a lame hyperloop.
There is something very wrong going on in Germany AND France where, despite the nice speeches, investment in railway infrastructure is being run into the ground. If nothing changes, expect disaster-level quality of service within a 5 years time.
You have to live in a world where there is no Netflix and no Disney/Pixar yet. Where the standard for mass-media japanimation is Dragon Ball Z. People had to wait for each episode for days if not weeks. At that point in time Ideaki Anno was a name only known to relatively few people, but we knew he could deliver stellar stuff. Evangelion started hyper-well animated and characters resonated with many viewers. Cool music too. The story arc looked promising with dark brooding villains and misteries everywhere. It was really something at the time. Where it ended is another (controversial) story.
Smart and productive people are happiest when they are free to do whatever they feel is worthy of their time and attention. One of the key to their productivity is that they don’t need to be told what to do every step of the way. Retire at 30 does not mean being unproductive, it means working on what you want, when you want. I have even met execs in large orgs that were essentially doing the job because they liked it. They did not need the salary anymore.
The behaviour described in the article makes me think of a goal-oriented AI. It does not require a lot of complexity and can exhibit very advanced and quite surprising behaviour.
Dude. TI-81 was my high school calculator. I got pretty famous at some point for managing to squeeze into it a decent RPG with monsters, health points and some story line. Other geeks were jealous and jocks patted me on the back for providing distraction. The challenge was the available BASIC program memory. We spent the next few months figuring out how to reduce the footprint to the bare minimum to add more gameplay. No internet at the time. Just our brains and the manuals. I chuckle at the idea of what we could have done if we had been hinted access to assembly and pixel flicker tricks to have 4 colours.