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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]

#71

Post by drtgh »

Ekaros wrote: post #67
russellbeattie wrote: post #60

I wonder how long the carbon fiber cable lasts? We've got 100+ years of experience with steel cabling, I wonder how carbon fiber compares. When it fails, it'll probably be by snapping. I hope there's lots of redundancy in place!

Multiple cables always. And it is basically epoxy coated flat piece. So I don't think failure model is that bad.

Unlike steel, there is a point at which carbon fiber will suddenly break like if it were glass, and this will happen without external warnings (micro-fractures non visible to human eyes).

In the video one can see in the cable what apparently seems to be metallic layers for this reason. Epoxy would only increase the stiffness and therefore the brittleness.

It is not my field, mere layman point of view then, but I can imagine that the revision of these cables would have to be based on ultrasonic or microscopic scanning to detect such unpredictable micro-fractures. I'm not sure if this cable would be suitable for a place with earthquakes or high winds.

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

#72

Post by cqqxo4zV46cp »

_xnmw wrote: post #53
Gigachad wrote: post #51

Earlier quoted context omitted.

I think this is generally agreed on. Most super tall buildings are heavily state funded and used more of a show piece demonstrating the prosperity and ability of the city. Commercially they just aren’t reasonable. China for example has stopped building these super tall sky scrapers because it’s far more economical to build lots of 40 level buildings than a few 100+ level ones.

Interesting how these generally accepted principles among “real” engineers are still poorly understood by software engineers. I always knew something like Heroku could never work reliably at a certain scale. The limits and tradeoffs of building something like an S3 are rarely even discussed.

Software engineers aren’t in the the same domain. s3 too hard to scale? Scale horizontally, have a directory service (DNS does perfectly fine!), and that’s a lot do the problem solved. It’s tantalisingly poetic and contrarian to try to draw more of a comparison here, but in a software systems context what you’re really talking about is decentralising your state, which is…WELL established as a scaling mechanic already.

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

#74

Post by jrs235 »

koolba wrote: post #7
cedws wrote: 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? “Shafted” is how the guy already in the elevator would describe the elevator going up to get the group when he wants to go down.

What would be worse than that is being on a low floor needing to go to a high floor or vice versa and someone getting on and pressing all the floors inside the elevator so it has to stop at each and every floor.

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

#75

Post by foxyv »

jvanderbot wrote: post #22

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.

I think your best bet would be a VirtualBox with Windows 95-XP on it or using DosBox. However there is an entire sub-reddit dedicated to the game where people have run it like 20 different ways.

https://www.reddit.com/r/SimTower/

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

#76

Post by HarHarVeryFunny »

flir wrote: post #68
HarHarVeryFunny wrote: post #31

Earlier quoted context omitted.

There was one at the university (in the UK) my Dad worked at that was used for years with zero incidents. Lots of things from chain saws to hover mowers, or cars for that matter, are unsafe if not used with due regard for safety.

Essex still has theirs, in the library: https://library.essex.ac.uk/paternoster

According to that link there's only two left in the UK now.

The one I was referring to was at Durham university, but it's not showing up via Google, so I guess it's no longer there.

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

#77

Post by duck »

jvanderbot wrote: post #23
robertlagrant wrote: post #9

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.

There is a pretty cool PICO-8 remake: https://www.lexaloffle.com/bbs/?tid=46087
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