Hyperbolic Time Chamber

The Hyperbolic Time Chamber from Dragon Ball is a space where you can train for a long time in a day.
Approximate Time Dilation from the Dragon Ball Wiki

Real-World Time Chamber Calculation
1 day 1 year 1 day → 365.24d=1y
1 hour 15 days, 5 hours, 14 mins and 24 seconds 1 hour → 365.24h
360h/24(hrs/d)=15d
5h
0.24h×60(min/h)=14.4min
0.4mx60(sec/min) = 24 seconds
1 minute 6 hours, 5 minutes and 14.4 seconds 1 minute → 365.24min
360min/60(mins/h) = 6h
5min
0.24min×60(secs/min)=14.4s
1 second 6 minutes and 5.24 seconds 1 second → 365.24s
360s/60(secs/min) = 6min
5s
0.24s×1000(ms/s)=240ms

Goku: We'll train for a year in a day in the Hyperbolic Time Chamber.