There must be some form of TCP/IP network connection between client and server for RAdmin to work. If the two are not on the same LAN, then this connection must be made via the internet (barring some direct WAN connection, such as a dedicated T1, which I doubt you have between your home and work). So, if your work computer is not connected to the internet, then no, it won't be possible to connect to it via RAdmin from your home.