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Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

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Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#42
post #3

Interesting video. I've often wondered what the most optimal elevator algorithm is. Imagine a scenario where a single person calls an elevator to go down, and just as they get in, a group of five people on the floor above also call the elevator to go down. We all know that the elevator would go straight down and then come back up for the people who called the elevator too late. The elevator could actually save time b…

[deleted]

Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#44

Earlier quoted context omitted.

If I remember the story correctly, the creator of Sim Tower[0] wondered the same, and discovered that the algorithms governing that were closely-guarded secrets. So he developed Sim Tower. [0] https://en.wikipedia.org/wiki/SimTower

So, somewhat related. Is there a way to play Sim Tower nowadays? I regret that I never got that last star, and think about it once or twice a year.

Try https://infinitemac.org/

Pick a System Software/Mac OS version (you probably want something like 7.5), then choose the SimTower disc from the CD-ROMs drawer at the bottom of the screen.

Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#47
post #3

Interesting video. I've often wondered what the most optimal elevator algorithm is. Imagine a scenario where a single person calls an elevator to go down, and just as they get in, a group of five people on the floor above also call the elevator to go down. We all know that the elevator would go straight down and then come back up for the people who called the elevator too late. The elevator could actually save time b…

The trouble is that the call button doesn't indicate how many people want to go in a given direction, just that there's more than zero with such a desire. If you could get people to input perfect information about where they wanted to go (ideally on the way to the elevator lobby, before having arrived there), much greater optimization would be possible.

Most modern buildings (2008+) don't have up/down buttons anymore, instead they require each person to input the exact floor they want to go to on a keypad. It's called "destination dispatch".

Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#48
post #29

In Australia (and I would imagine elsewhere) Apartment complexes have a body corporate which all owners are voting members of, and they have to vote two annual costs: the operating fund, and the sinking fund. the latter has to pay for building maintenance such as painting, and lifts. These are the two notoriously most expensive repairs in the life of a modern building: a complete re-cabling of a set of lifts for even…

Why so much? They're important cables, but surely not made of unobtainium and not that rare of a product with the amount of elevators in existence.

We had floods 2 years ago where I live. 20+ apartment complexes lost significant electrics for their lifts, and Thyssen and Otis had 6+mo back order supply issues.

Supply chain logistics behind things like lift parts, puts pressure on pricing. That and compliance. Every inch of a lift cable has to be checked and certified.

Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#49
post #18
post #3

Interesting video. I've often wondered what the most optimal elevator algorithm is. Imagine a scenario where a single person calls an elevator to go down, and just as they get in, a group of five people on the floor above also call the elevator to go down. We all know that the elevator would go straight down and then come back up for the people who called the elevator too late. The elevator could actually save time b…

> Could one shaft serve a lower set of floors while another shaft serves a higher set of floors to minimise 'wasted' time travelling up and down? That's actually completely standard for very tall buildings, and of course the shafts that e.g. serve only the higher floors don't go all the way down, because the space used by elevators becomes an even bigger problem than the travel time as buildings get taller. Another o…

There were discussions to put multiple cars in the same shaft. Obviously there are some complications.

Re: Elevator Expert on How to Move 10k People Up a 118-Floor Skyscraper [video]

#50
Reminded me of something I have been thinking about lately: a centralization-cost curve. The engineering problems that go into building things of a certain scale eventually become more expensive than simply breaking up the problem into smaller pieces. It may be much easier and cheaper to build 2 buildings 59 floors high compared to one 118-floor building, but not cheaper or easier compared to 118 one-floor buildings.

Example from tech: Amazon S3 and cloud services in general. They benefit from economies of scale, but only to a certain extent. And I have a hunch we are reaching hard limits on what AWS can handle. S3 in particular may be at a breaking point as I have noticed that the cost and speed of storing data there is now ridiculously bad.

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