If you are using Soft-eLicenser (which is the default one), you can install Cubase Elements to any Number of computers, but you can activate it on one Computer at given time only. If you want to switch to another computer, you have to reactivate.
But you can transfer the license to the USB-eLicenser. Then you can take the USB-eLicenser with you. Where the USB-eLicenser is plugged in, Cubase will run.
The same is with Cubase Artist. But you can use an USB-eLicenser only. There is no way how to put the license to the Soft-eLicenser.