91–100 of 153 posts
Buses bunching might be more noticeable because buses tend to stay in the right lane.
I enjoyed the callout to this when I was reading Google's Percolator paper a few years ago: > The random-scanning approach requires one additional tweak: when it was first deployed we noticed that scanning threads would tend to clump together in a few regions of the table, effectively reducing the parallelism of the scan. This phenomenon is commonly seen in public transportation systems where it is known as “platooni…
This is possible with public transportation too. Trains run express and skip stops all the time. I think that would be too much hassle with buses but it's possible.
Would it help to have the trailing bus pass the leading bus when they bunch up? My reasoning: (1) As the article said, full buses move slower because more passengers means more boarding/unboarding time at stops. (2) The lead bus is the fuller, slower one. Slower bus in front means buses get closer together. (3) If one bus passes the other, then you have the faster bus in front and the slower one behind. They should t…
This is very common in Manhattan. Whenever I saw a full bus, I'd skip it and wait for the next one, because it was almost certainly going to come along within 5 minutes and be pleasantly uncrowded. On a busy route, it's the sensible choice. On longer-distance commuter routes, where the scheduled times are 30-60 minutes apart, I wouldn't usually take a chance on waiting for the next one, but I even did that on occasio…
If you're at a bad rail stop (like the first one outside of the central part of a city going outbound at rush hour) it's not uncommon to have to wait two or three trains just to be able to board. In a city like Singapore or London it might not be too long since many of their trains are automated (in Singapore they're all automated/driverless) and the busy lines are allocated enough cars to arrive 1 minute apart or le…
Note that headway is measured between the arrival of trains, meaning the train has to come to a complete stop, let people get on & off, close doors, speed off and have another train stopped all within that period! So a 90-sec headway will feel like less than a minute to users.
Interesting, that simulator shows buses that are often full. I think that's a rather rare case and know of a pretty graspable reason why lower fill buses clump up quite a bit. Assume that a stop produces a customer every minute or so, if a bus is five minutes late to the stop (lets say due to traffic) it will take a bit longer to load customers than normal adding slight amounts to its delay over time - concurrently,…
Would it help to have the trailing bus pass the leading bus when they bunch up? My reasoning: (1) As the article said, full buses move slower because more passengers means more boarding/unboarding time at stops. (2) The lead bus is the fuller, slower one. Slower bus in front means buses get closer together. (3) If one bus passes the other, then you have the faster bus in front and the slower one behind. They should t…
You are forgetting people who would want to get off that stop, so this is may not be an option.
Meanwhile, the one following behind will be emptier, and thus less likely to need to stop, meaning it can easily pass the one in front (while that one is at a stop for entering/exiting passengers) and then itself take on more passengers at the stops ahead --- which then gradually slows it down too, but at the same time the one behind will be mostly emptying.
I'd say it is reasonably self-balancing.
Earlier quoted context omitted.
You could probably have a computer calculate which stop the trailing bus should jump ahead to. Then you have the trailing bus switch to "out of service" mode (so it doesn't enrage people when it passes a bunch of stops) and skip ahead 4 or 5 stops or whatever the computer decides is optimal.
It would be horrible if the slow bus behind was actually too full to pick up people so you have an empty bus passing stops that the trailing bus will also skip!
Earlier quoted context omitted.
The London Underground sometimes skips stops in order to uncongest lines after a temporary delay. They tell everyone on the trains that will be skipping stops that it's happening, and anyone who wants the intermediate stops has to get off and catch the next one. This probably wouldn't work for buses that take a lot longer to load/unload though...
This is amazing! I wish the DC Metro did this.
Here's an article talking about it: https://ggwash.org/view/38198/expressing-trains-helps-metro-...
The NY subway will also sometimes have trains switch from local to express or vice versa to help recover during delays.
I enjoyed the callout to this when I was reading Google's Percolator paper a few years ago: > The random-scanning approach requires one additional tweak: when it was first deployed we noticed that scanning threads would tend to clump together in a few regions of the table, effectively reducing the parallelism of the scan. This phenomenon is commonly seen in public transportation systems where it is known as “platooni…
This is possible with public transportation too. Trains run express and skip stops all the time. I think that would be too much hassle with buses but it's possible.