Do Google Drive and Ubuntu One have the same concept?
I just have an Ubuntu cloud account and Google Docs.
Basically, yes, they're the same.
To all intents and purposes, the 'cloud' is the internet. Google Drive, Ubuntu cloud services, MS Skydrive and the multitude of other 'cloud service providers' essentially give you the ability to store information in a way that it can be retrieved by you, anywhere there is connectivity to the 'cloud'. This type of cloud computing is known as Storage as a Service (STaaS)
The implementation details differ: some providers link a physical drive on your machine to the cloud, so that you are accessing information stored on your own hard drive, some give you storage space on their hardware, but the end result is the same. Your data is held in a location accessible by the internet, so that you can access it, whenever you are connected to the internet (cloud).
To answer simply, yes, they are the same concept. Ubuntu One and Google Drive are competitors that seek to provide the same service of keeping your data for you so you can access it anywhere. There are lots of practical differences between them, and reasons why one would be more convenient than the other, but just like Facebook and Google+, they're the same kind of thing. Mind you, the same reasons apply to having multiple cloud storage accounts as having multiple social networking accounts: different ones are better for different things.
Edit: I automatically assumed you meant Ubuntu One when you said an "Ubuntu Cloud account", is that what you meant? Canonical also has the "Ubuntu cloud" name assigned to something else entirely.