Power On and Off Screens at a certain time

[Cesar Covarrubias <cesar uci edu>]

Good Morning,

I was curious if anyone knew what command to invoke to power on and off
the monitors connected to a system at a given time. I assume that I will
have to setup a cron job to get it at the specific time, but what
command do I use to force the monitors off? 

Thanks!
Cesar Covarrubias