How to synchronize time between Windows and Linux dual systems
On Ubuntu:
$ sudo apt-get install ntpadate //update time on Ubuntu
$ sudo ntpdate time.windows.com
$ sudo hwclock --localtime --systohc //update local time to hardware
On Ubuntu:
$ sudo apt-get install ntpadate //update time on Ubuntu
$ sudo ntpdate time.windows.com
$ sudo hwclock --localtime --systohc //update local time to hardware