If there are any programs you would like run at these scheduled times from the administrator account, its easy to just copy the program or batch file to that directory, you can even make a link to the program if you like. Otherwise, see the next section about creating a crontab file for a regular users account. To have your time updated every night, edit a file called /etc/cron.daily/z-sync-time with the following.
/usr/bin/rdate -s time.ucla.eduThen use the chmod command to make it executable.
chmod +x /etc/cron.daily/z-sync-time.I prefixed the filename with a z, because the files are executed alphabetically, so this program will be executed last.